Double Adjustable Shocks "Waste of $$ or Not"

[bjuice]

i have a pretty smart chassis man that has built/dynoed his share of shocks. He steered me clear of the double adjustable shocks..i ask him why?..he advised me that there was NO WAY that the bleed over from the compression and rebound could be seperated in one canister as the double adjustable shock is designed....although the claims are made that it can be done by the manufactures, he advises that unless there is a independant canister there is no way both compression and rebound can be accuratley (seperated) attained from one cylinder....i went to the BIG BOYS (NHRA SOUTHERN NATIONALS) race last week and looked under several of the BIG name cars such as Greg Anderson etc...low and behold i saw double adjustable shocks but with a independant canister with remote wiring (NONE of the Double adjustable stuff being sold as we know it)....i do not know what brand they use cause i could not get close enough..( i assume they have them custom built or something to that degree) but i will list a few brand name manufactures that build these shocks..they are the TRUE double adjustable shocks and they are very HIGH PRICE...
Now i AM NOT trying to steer anyone away from buying a double adjustable shock..its your money do with it as you will..i just wanted to give you the side of a true double adjustable shock that the manuafactures will not tell you...I personally have single adjustable shocks and will not touch the SO-CALLED double adjusteble shock for the reason i am stating in this thread..its a waste in my opinion. here are a few brand names and a little literature from one of the sites..PLEASE DO YOUR OWN RESEARCH BEFORE YOU GO PAYING FOR A DOUBLE ADJUSTABLE SHOCK..."Get what you pay for" AND BE YOUR OWN JUDGE !!!!!!.......

( THE ABOVE IS MY OPINION ONLY. IT IS NOT INTENDED FOR NOTHING MORE THAN A PERSONAL OPINION !!! )

#1- OHLINS #2 BILLSTEIN #3 PENSKE....

below is some info from the OHLINS site on the introduction of this shock.


Introduction
The TTX damper is the culmination of three decades of Öhlins’ successful participation in world championship events winning more than 100 World Championships. Many years of work together with some of the world’s most successful racing teams together with advanced dynamic analysis methods developed at Öhlins Racing headquarter in Sweden has given Öhlins the unique knowledge needed to design the TTX damper.

The Öhlins TTX damper, originally developed for formula racing, is designed to handle the demanding damping characteristics needed for all types of tracks, from street courses to super speedways

The TTX damper is fully adjustable with maximised damper response together with qualities you’ve never seen before when it comes to "settings".

Low and high speed compression and rebound damping are externally adjustable and fully independent. The adjustment range is huge with equal increments of force throughout the adjustment range. Even the shape of the damping curve can easily be changed. All adjusters affect the flow from the main piston, not the piston rod displacement volume.
Some classes may need the TTX 40 with 3 or even 2 adjusters. For this puropse there is a needle housing that uses the existing parts in the 2-way adjuster and transforms it to be a 1-way adjuster suitable on either compression or rebound or both. Part number for this needle housing is 05953-03. Preload changes is made by adding shims on one or boths sides of the coil spring. Shims that should be used in the 1-way adjuster are: 00610-16, 00615-16,00625-16 and 00630-16.

The compression damping forces of the TTX damper are not, as in a conventional damper, caused by a pressure drop on the rebound side, but by increased pressure on the compression side. This reduces the risk of cavitation and makes any reservoir valve or high gas pressure unnecessary. So, no balancing of reservoir damping to main piston damping is needed to avoid cavitation and improve damping response. Maximum response and minimum risk of cavitation will always occur. With no reservoir valve, the internal pressure of the damper unit will be kept to a minimum. The low amount of hysteresis results in excellent short stroke/high force performance. Also, a very low gas pressure can be used without any loss of damping performance.

Along with the damper comes a unique Valving Reference Program (available for download free of charge at www.ohlins.com/Automotive/Products/FormulaSportscar). This computer model of the damper will allow you to find damping curves without a dynamometer. It will reduce building time tremendously and allow exact damper adjustments in pit lane. The TTX product will revolutionise the work for mechanics and engineers in the racing business.

This manual text is based on TTX dampers starting with Öhlins part number TTX NE0. These are through rod type dampers loaded with several new concepts. As always, all dampers are tested before they are delivered to the customer. In keeping with Öhlins long tradition of perfection, quality is outstanding and long life is to be expected.

Welcome to the World of Öhlins.

Design Criteria
After the Öhlins TT44 was introduced to the market in 1996, it very quickly became one of the most popular dampers in formula racing. For some period, more than 95% of the cars in The Champ Car World Series were using TT44 dampers.

There are several reasons why the TT44 became so popular. One reason is that it came with some new features not available on other dampers. One of them is the powerful low speed adjusters, totally independent and with the compression adjuster restricting the oil flow from the main piston, not only from the piston rod displacement. Another is the compression high speed adjuster, giving new possibilities to reshape the compression curve.

When designing the new TTX, the goal was to come up with a damper which would be just as big a step forward as the TT44 had been. Highest priority should be not only to design a damper with excellent performance, but also a damper easier to work on and use than any other product available.

During the development several patent applications were made.

Six of the most important design criteria for the TTX are listed below.
1. No reservoir valve
The damper design should be with no reservoir valve. In dampers where reservoir valves have to be used to avoid cavitation, one more parameter has to be optimised – the right amount of reservoir damping.

The hysteresis will be minimised, as no reservoir valve has to be used. All damping comes from the pressure drop over the main piston. Damping forces from a reservoir valve always causes more delay in the damping force build up. See chapter Hysteresis for more information.

Using reservoir valves always increases the internal pressure. The friction from the piston rod seal/seals can be kept low because of the low internal pressures.
2. Main piston flow
Another criterion was to have all the adjusters regulate the flow from the main piston. This will give the maximum pressure area and because of this, the maximum oil volume to regulate.

The larger the pressure area is, the lower the internal pressure will be for a given damping force. The lower the internal pressure, the less flex there will be. The flex is caused by expansion/compression of the damper body and compression/expansion of the oil. The result is excellent short stroke/high force performance.

With a large volume of oil passing through the valves , it becomes easier to control the restriction of the oil. In other words, the matching of dampers will be improved.
3. Full adjustability
On the TT44/TT40, it was never possible to use a high speed rebound adjuster in combination with a high speed compression adjuster. On the TTX, we wanted to be able to combine those two while keeping them completely independent from each other, as with the low speed compression and rebound adjusters.
Poppet valves preloaded by coil springs were picked to become the high speed valves, as they can be made very compact in size and precise in opening pressure. This type of valve very often gives an abrupt opening characteristic, resulting in a sharp "knee" in the damping curve. To make the "knee" more rounded and to be able to change its shape, some shims are added to the face of the poppet valves. By changing these shims, the shape of the "knee" can be affected.
4. Simple valve changing
Even if the adjustment range of the external adjusters is huge, sometimes there might still be a need to change the valving of the dampers. In other words, change one or several of the following parts: poppet valve/valve seat, coil springs and nose shims. As this very often is done at the track and has to be done quickly, this job has to be simplified as much as possible. Compared to reshimming a conventional damper, any of the changes in the TTX will be a lot quicker. The result exceeded our demands.

Also it should be possible to fill the damper without a vacuum-filling machine, as this otherwise would be a limiting factor.
5. Through rod damper
A through rod damper has some technical benefits. One is packaging, which is a main issue on formula cars. The reservoir volume can be very small, as there is no piston rod displacement. Here no external reservoir is needed. Also there is no gas force pushing the piston rod out of the damper body. (The word "nose pressure" is sometimes used for this force.) Here the nose pressure is zero. This has several advantages. The nose pressure doesn’t vary due to temperature changes and you don’t have to fight the gas force when installing the damper on the car or in the dynamometer.

Designing a through rod damper gives the possibility to separate the rod bushings and keeps the distance between them constant. If coilover springs are used, the amount of friction will be tremendously reduced.

As the piston area for compression and rebound are identical, the damping forces will be the same if the same valving is used and the adjusters are set the same. To some degree, this simplifies the use of the damper.

For all the above reasons, race teams have been interested in through rod dampers. Also, when introducing the TTX, we wanted it to be something very different from the other products out on the market.
6. External clocking
Another strong side of the TT44/TT40 was the possibility to clock the reservoir bracket at any angle. This function we wanted to keep on the TTX damper, to ensure an optimum installation on any car. Just as on the TT44/TT40, the clocking of the adjusters on the TTX in relation to the top eye should be possible to change without opening the damper.

[slowman]

dam brian my eyes are watering for reading lol. i'm not a chassie guy but i counldn't get my cal-tracs to work without them. the car would load and then unload with singles. as so as i installed doubles and adjusted the rebound it stoped unloading. i had this same talk with keith from skinnykid racecars and he uses doubles on everything he builds. after reading your post i'm wondering even more about the topic thanks alot brian make me more confused lol.

[bjuice]

mission accomplished LMAO.....this is a modern day (FORUM\ PHILLY BUSTER)...LOL...

serioulsy..i can copy and post all day long the information on TRUE double adjustable shocks and the reason why they work.


i know there is going to be someone on here that will strongly disagree that these shocks work (off shelf double adjustable)...and thats COOL !!..i was one of those people at one time..but what i ask from the person that challanages this question is to give either your opinion or copy and post ( as i did lol) the facts why a double adjustable shock will truly work (without bleed over) utilizing the same canister/piston etc....



if you stop and think using just common sense...

compression and rebound using the same cannister....COULD IT NOT BE POSSIBLE THAT THEIR COULD BE SOME BLEED OVER PROBLEMS HERE ?...if someone can prove this theory beyond a reasonable doubt i would like to hear it....If this could not be the case then why do they make double adjustable shocks with external cannisters outside of the crazy price tag...


this should get a good rise here...LOL..

I know its a lot of reading notice the bold print....its s lot of glooobly- goo but in a nut shell they have the rebound and compression canisters seperate

Brian

[Racefab57]

I believe off the shelve doubles are for the masses! If you can afford the others, great ! I beleive this to be the way it is. I also believe they work to some degree!!! but not like the others, I have stranges on my vette, and konis on the camaro! good post bjuice! I would also like to talk to you bj some time about the vettes!!!!! david, ( and by the way whats with the sub names next to your name, when you post? ) like expert builder, etc....?

[mcracecars]

Interesting post....
I can see your point here Brian. I know some guys have picked up a little et by going to a double, but I think that is more because of changing from a worn out or cheap shock, to a better quality.
I have always felt that the more adjustment you can have in a car is better, as long as you are going to take the time to adjust, which a lot of guys dont, so then double adjustables would be a waste of money.
Another point of interest, a large number of pro mods are built using Santuff coil overs, at a substansially higher price than konis. They say they are a few hundreds quicker than the konis. They also are a double adjustable. But I have wondered how a small company like Santuff can make a better shock than koni

[GBoven72]

Greg was using Lamb but not for sure now. I can ask Nate next time I see him and let you know.

[bjuice]

I believe off the shelve doubles are for the masses! If you can afford the others, great ! I beleive this to be the way it is. I also believe they work to some degree!!! but not like the others, I have stranges on my vette, and konis on the camaro! good post bjuice! I would also like to talk to you bj some time about the vettes!!!!! david, ( and by the way whats with the sub names next to your name, when you post? ) like expert builder, etc....?


sounds good...i am working on the vette as we speak..i spend much time in the shop...my cell phone doesn't pickup down there Metal building. :( :( ....the sub name is soemthing that RJ ADMIN has thrown in there for fun...i guess you have seen this by now...pretty funny stuff isn't it !!!!..


brian

[edvancedengines]

I have wondered how a small company like Santuff can make a better shock than koni


Ed,
It is called caring with attention to quality control. In my opinion over the past two years Koni is at the bottom as far as quality control goes. I have seen a couple of new very high dollar shock setups from them that were junk right out of the box. Or almnost out of the box. Matched paiers of electric shocks with completely different charastics as delivered. Guys don't know this and install them and their cars get really screwey until they find what the problem is. I know of only two guys I personally know though that experienced this. There agtain not too many peoiple are spending several thousand dollars on shocks either. In both of those the shocks were sent to Roger Lamb and he made them work perfect. I have also seen a few of the Koni that taking them form the box and adjusting the loose just by a hand feel do feel different. So I prefer either the Strange or the Afco in Double Adjustables if Santhuffs are out of the budget.

To answer the original question in my opinion;
If you can afford them and will use the additional tuning capabilities a good set of Double Adjustables is probably the best money you will spend in suspension parts. Like Esd said though, if you are just going to leave them set in one place and not use the tuning capabilities you have with them, save your money.

Double adjustable front shocks and front struts are also very helpful if you can afford them and will use the tuning they give. I have a customer now that has the Strange Aluminum Struts but with no adjustments. He could sure benefit from the adjustable ones if he had had them.

I personally like a raer shock to ride soft and the front shock to also ride soft if possible. Problem with front shocks is that you need them stiff to a point in cokmpression for when coming down off wheelies and you can also use a rebound or extension adjustment to help tame the front down when you have already tyed the front travel down as far as you can and still have some down track suspension.

WEith the rear double adjustable, once you get the bars in somewhat of a baseline, in most instances from track to track or changing track conditions, a rear shock adjustment just may be all you need to make it work.

have a pretty smart chassis man that has built/dynoed his share of shocks. He steered me clear of the double adjustable shocks..i ask him why?..he advised me that there was NO WAY that the bleed over from the compression and rebound could be seperated in one canister as the double adjustable shock is designed....although the claims are made that it can be done by the manufactures, he advises that unless there is a independant canister there is no way both compression and rebound can be accuratley (seperated) attained from one cylinder....i went to the BIG BOYS (NHRA SOUTHERN NATIONALS) race last week and looked under several of the BIG name cars such as Greg Anderson etc...low and behold i saw double adjustable shocks but with a independant canister with remote wiring (NONE of the Double adjustable stuff being sold as we know it)....i do not know what brand they use cause i could not get close enough..( i assume they have them custom built or something to that degree) but i will list a few brand name manufactures that build these shocks..they are the TRUE double adjustable shocks and they are very HIGH PRICE...
Now i AM NOT trying to steer anyone away from buying a double adjustable shock..its your money do with it as you will..i just wanted to give you the side of a true double adjustable shock that the manuafactures will not tell you...I personally have single adjustable shocks and will not touch the SO-CALLED double adjusteble shock for the reason i am stating in this thread..its a waste in my opinion. here are a few brand names and a little literature from one of the sites..PLEASE DO YOUR OWN RESEARCH BEFORE YOU GO PAYING FOR A DOUBLE ADJUSTABLE SHOCK..."Get what you pay for" AND BE YOUR OWN JUDGE !!!!!!.......

( THE ABOVE IS MY OPINION ONLY. IT IS NOT INTENDED FOR NOTHING MORE THAN A PERSONAL OPINION !!! )

#1- OHLINS #2 BILLSTEIN #3 PENSKE....


I would say that your pretty smart chassis man is maybe a little too smart. There is no way possible to begin to compare the needs and the requirements of shocks for drag racing to those of FR1, Can Am or etc. To begin with most of those shocks are computer controlled and cost over $50,000.00 each. Greg Anderson and Jason Line's cars had them for a very short time this season until NHRA said a BIG NO.

The Penske Hydraulic Shock is infinetly Double Adjustable and doesa require a separate resorvoir. That shock is as far as I know still NHRA legal and is used on some of the Pro teams. The Koni Electric and the Strange Electric is legal is is used on many of the Pro Teams after they have been gone througgh by Lamb. Roger Lamb also builds his own shocks and they arew sweet and are pricey.

Bear in mind that all 4 shocks used in NHRA Pro racing to have sensors sending load and travel information to Data Logs so they can see what is talking place.

Your chassis expert is far smater than anyone I know in High Horsepopwer racing. The shocks we refer to now as off the shelf double adjustables a few years back were the best you could get for drag racing and were heavily used by everyone at the top. The very top guys took thaose same shocks from Koni, Strange and even Monroe(Made drag shocks at one time) and would send them to Roger Lamb with all car specs and Roger would calibrate them for the car's needs. Lamb Industries does have a shock absorber dyno to test the clibrations and dampening forces.

I vehemently disagree with anyone who thinks that using simple single adjustable shocks in high horsepowered cars is the best idea. You will not finbd any on anything that is quick and has excessive power. I do work with customers having 1,000 to 3,000 hp. I consider a good doubgle adjustable to be a requirement when cars get this powerful and with the chassis setups we have to do to keep them hooked and not unloading the tires.

With lower powered cars, single adjustable is ok.

Never equate suspension needs or even engines used for serious drag racing with FR1 stuff.

Bilstien Shocks arew unique in that they do not use a pressurised chamber that holds a pressure against the piston with a force toward extension like most gas chagred shocks do. The Bilstien is a gas cushion shock and has unique valving that comes into play when the dampening needs require it. In my opinion the Bilstien is the best for all around driving needs. Not for Drag Racing.

I shudder to even think about a 1,500 hp to 3,000 hp car going down the track with only a single adjutment capability which cay only be adjusted for eithe launch or ride but not both. I would bet that most Pro drivers would refuse to drive it.

Also tell your chassis expert to do some research into performace shocks. None will have only one chamber or cavity inside them. Just becuase it looks like a round tube don't be fooled. Inside is multiple cavities, chambers and valves.

Ed

[topsportsman1]

Nice thread here guys,lots of knowlege and advise to be had here in this thread.

I myself personally like the double adjustable shocks,I have a couple different kinds,but I got Afco's on my car at the moment.

I do have a set of penski's to with the co2 canister attached to the shocks,that are also double adjustable,and fresh from the dyno. :P

[davis419b]

" Penski is bad to the bone" I had one on a Davis Swingarm Dragster and i could adjust it to any size motor with nothing more than a toothpick.

[bjuice]

:?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?: :?:

#1- I would say that your pretty smart chassis man is maybe a little too smart

#2 Your chassis expert is far smater than anyone I know in High Horsepopwer racing

#3- Also tell your chassis expert to do some research into performance shocks

WHY ED


Brian

[edvancedengines]

Brian,
Most shocks designed and built for performance and for certain racing shocks do not only contain one chamber.

he advised me that there was NO WAY that the bleed over from the compression and rebound could be seperated in one canister as the double adjustable shock is designed....although the claims are made that it can be done by the manufactures, he advises that unless there is a independant canister there is no way both compression and rebound can be accuratley (seperated) attained from one cylinder

The one round shock absorber does contain many separate chambers with several different load sensing valves. Depending on the brand and on which shock they are all made different but I do not know of any that only have one chamber in the way he is talking about one canister.

You probably live in a house. That house is only one building. Inside that building are several rooom unrelated to each other. To separate those chambers/rooms you have doors. Shock absorbers have internal valves and not just one but several. Some of these valves are pressure sensitive and some are speed sensitive in relation to pressure changes.

Do not think of a shock absorber as a simple hydraulic cylinder with a piston and ram. Do not think of a shock absorber as a tire pump . iT is a designed complex piece of engineering with comp0lex valed controlled chambers each for different reasons and functions.

Years ago Carrera tried to get into the Drag Racing market and made several different shocks for drag racing. They abandoned the idea a few years later becuase their shocks were inferrior to the needs of drag cars as compared to the other front runers in the market like Koni and Monroe. Monroe made a great aluminum coil over for drag racing fore a few years but dropped out becuase it was not profitable for the amount sold. Armstrong which is big in formula racing tried the drag shock market and just did not make the grade. Their drag shocks were like their Formula 1 shocks of the day just with longer travel.

What you chassis man is telling you is defying all that serious drag racers have found to work and be sucessful for years.

..i went to the BIG BOYS (NHRA SOUTHERN NATIONALS) race last week and looked under several of the BIG name cars such as Greg Anderson etc...low and behold i saw double adjustable shocks but with a independant canister with remote wiring (NONE of the Double adjustable stuff being sold as we know it)....i do not know what brand they use cause i could not get close enough..( i assume they have them custom built or something to that degree) but i will list a few brand name manufactures that build these shocks..they are the TRUE double adjustable shocks and they are very HIGH PRICE...

If you got near enough to Greg Anderson's shocks to see them, consider yourself to be fortunate. As I stated earlier in the beginning of the first part of this racing season that team was using shocks of the latest F1 technology with remote controllers were connected to onboard computers and the cost of only one set exceded $100,000, for just one car. Maybe that is what you saw. Maybe you saw a Penske Co2 Chamber attached to the Pro Stock Co@ microprocessor controlled shocks.

I think I have said enough.
.

I try to help. If My info is no help, pass it up and don;t waste your time reading them. I assure you it takes me much much more time to write them, than it takes anyone to read them. I can not type and I do the best I can.

A do agree that even the lowliest double adjustable does cost more money. MY OPINION. It is the best money for suspension parts you will spend.

I also agree that if you are going to buy a good double adjustable and are lazy and never chnage any shock tuning, to save your money and just buy a cheaper shock.

Ed

[bjuice]

Ed- it may be hard to believe but he and i both know that the shock was a little more detailed than just a cylinder and a piston..remember this is inernet and e-mail is almost impossible to convey everything and be totally satisfied the person reading is comprehending what your TYPING.


now its without question you are far above my intelligence on the shock thing.....

but one thing i can say for sure is that there is a GOOD VALID reason why they have made the true double and triple adjustable shock with a remote canister for fine tunning the compression....there was a reason they felt this should be indepenedent..i can assure you i am going to google it to death until i find the reason it went this direction..when i find the answer i am going to post it..i think i am close with some material i read last night.

Since this thread i have read up on the shock thing and i can copy and paste much information of how and why the remote cannister has come into play...if Anyone out there is interested just Google it and you will see yourself that there is some legit debate in this area.


Now as for Getting too Close to Greg Anderson's car...thats not as hard as you make it sound..for starters he is a very close to mutual friend of Greg and i. as matter of fact Lindsay speaks to him by phone on a regular basis.

Plus unless you haven't been to a BIG NHRA POWERADE RACE LATELY..you can walk right up within a few feet of anyone's car..definatley close enough to look at the shocks....what i saw 3 weeks ago on Gregs car wasn't the double adjustable shocks as the common joe knows it....it was a remote canister with a #4 braided line running to the mian body of the shock..NO OUESTION a remote double adjustable canister.


so i will ask you this question again..."Can you prove with facts" that a double adjustable off the shelve shock will not have any bleed over issues invloving compression and rebound.....
If you say there is No possibility of this happening then please educate all of us why you feel this way with facts.also explain why the external canister was developed if there wasn't some fine tunning issues here.


this is a good info and i appreciate all of the time you take to share this info..this is really teaching people the other side of things..i believe so anyhow.

thanks brian

[topsportsman1]

Brian,
Did the shocks look like these? Ooops maybe I shouldn't have posted these?



http://img404.imageshack.us/img404/6150/penskelh5.jpg

[edvancedengines]

Brian,
I am far from a shock expert. I only know so much. I have had the opportunity years ago though to see a fully cutaway version of the Pro Stock Double Adjustabe that Monroe was making. It was made from a clear material for show demo purposes and I was really impressed. I also saw the similar thing in the Bilstien Gas Cushion shock which was different but displayed the same with the clear material shoing all the valves, the fluids etc. Just by moving them rapidly by hand I could see the differences when the gas was introduced by the complex valving system and was again recovered in a separate chamber. The Monroe was a oil operated shock with gas preure introdiced in needed amounts to keep the oil from aeroating. The Bilstien was a Gas Cushion shock that was far different in design.

I think that the shocks that Tom posted the pic of are the Co2 Chamberd Penske Pro Stock style shock, The extra canisters are for a Co2 gas.

IN my opion Roger Lamb is the foremost authority in drag racing shocks and it is similar to what is being called off the shelf double adjustabes that he modifies for serious racing in the top cars. If you buy the best car that Tim McAmis, Jerry Haas, Jerry Bickel, Rick Jones, Don Ness, and others make for the ultimate drag racing class of NHRA Pro Stock, you will get either the Co2 Penske with controller or the Strange or Koni Electronic with controller. Before these two options existed the double adjustabe that Koni, Afco, and Strange sells were the hottest thing available. Like I said before, most of the real serious racers do send their shocks to Roger Lamb for re-calibrating, or they buy shocks from him.

This is my last post on this subject. I have no proof and really don't care if anyone disagrees with what I have written or not. I go by memory in ust about everything I post. So what is in my head can not be proven to anyone.

If anyone really cares to find out more the information is available. Call any of the Pro Stock builders and sk for shock recommendations.

Ed

[bjuice]

Ed- Yes it looked like this along with some electrical type of apparatus that i am sure is the controller part of what you mentioned.

i do not mean this post to seem like i have challanged you in any way. i expected my original post to be questioned but looking back i would have worded some things differently..but hind sight is 20/20..

but it sort of goes hand in hand with my Chassis man stating that bleed over does occur causing fine tunning to be some what of a problem.


I CAN HONESTLY SAY I HAVE LEARNED MORE FROM YOUR POST IN 3 WEEKS THAN I HAVE LEARNED ON THE FORRUM IN 3 YEARS..
AND FOR THAT I THANK YOU SIR !.

[sp2816]

I am not a chassis guy, but I am an engineer and I do understand what Ed was talking about. There are differences between things that will work for the space shuttle vs most of our race cars. The thing that has to be remembered Brian, is that ProStock is not for the "normal" person. I love ProStock and we have a lot of the ProStock technology in our cars, but to a degree it has been "down sized" for normal racers on a budget. Pro Stock is trying to find every .001 of a second that they can, so if they can change a shock to get rid of the least amount of variable, they will. They have the carbon fiber driveshafts, gun drilled axles, and the list goes on. These are items that you would not necessarily need for your Camaro, but would be nicer for your Corvette. The same thing goes for the top of the line shocks.

I have the single adjustable shocks on rear of my car with 12 settings, but set at setting #4. With my limited use with them, I have found that #3 is too soft (walks around on the top end) and #5 is too stiff (spins the tires harder at the start) The other settings were useless on my car, so I would in time step up to the double adjustable shocks to have a little more range. They wouldn't be as good as the new Pro-stock style, but they would work better on my car. It really depends on what you are expecting out of them, how big your budget is, and how fast your car is. The double adjustable shocks that we can easily purchase now were used on the Pro-stock cars of the past until they found a little better way to adjust the car.

From what I remember Warren Johnson talking about the pro-stock shocks several years ago, was so that they had the external resevoirs and CO2 cannisters was so that they could change the valving as the car went down the track and be a little more precise. If all of the valving is internal, it is more difficult to change for different sections of the track. The shocks hold the car up a little more at the beginning for better traction and then start letting it settle more as it goes down the track for better aerodynamics.

Bill M

[bjuice]

hey Bill...i agree with everything you just said.

i think this thread is turning into something that its not as many of them do.

the baseline question was:
" does the double adjustable ( off the shelve)" shock stand a possibility of a bleed over from compression and rebound since its housed in the same body..
My chassis Guy says Yes and he has proved it with his shock dyno..

i do not think i got 'NO' from the last replies but got alot of other GREAT information.....( no sarcasm)



i used several TRUE double adjustable manufacture names to be able to show people the difference in this type shock. ( EXAMPLE ONLY)

the prostock guys were used as an example because they are on the cutting edge and will use the best route when it comes to their shocks.

Rj forum caters mostly to novice to weekend warriors (including me) who's cars are on the lower HP levels compared to the Pro-mod/pro-stock cars.....with that said the Novice racers are the ones that are going out here and buying the double adjustable shock when they really never need it to begin with..

so i was just trying to shead some light with these people on the difference in a true double adjustable shock VS what they are buying from chassis engineering etc.......does the off the shelf have greater range of adjustment ? ..YES.....is there a grey area of accuratley adjusting them because of rebound and compression Bleed over ?..My opinion is YES....anyone could find FACT based ionformation to back this up by GOOGLING double adjustable shock and being prepared to take some time to read mountains of information regarding the developement of the independant shock and why it was developed...

i have yet to find information supporting the opposite :?: :?:

i am still searching on my own and asking from members on the forum if you say "NO" there is not a chance of bleed over please provide me with facts to back this up.Even Ed with all the experience and advise he shared with his reponse (with respect) cannot state without a doubt with facts that bleed over is not an issue with the off the shelve double adjustable shock..

i personally believe that the (off the shelve double adjustable) shock has some issues in this area, this is why the newer independent shocks has been introduced because they were missing something in the finer tunning of this shock and they narrowed it down to the seperation of the compression/rebound by means of an external canister.

i am not telling anyone to go out and buy a pair of these shocks but i felt some would like to know the history of the finer tunning portion of the shock.......

is it worth it ?? that all depends on what you are wanting to do..your car,your budget...etc.......


i am like Ed at this point i have said enough,,anything further and i am just repeating myself......i will close my portion of this thread with saying if anyone out there has ANY fact based information that bleed over doesn't exsist in the off the shelve shock please let me know..

i think you know me well enough that i can except different opinions on all subject matter and i never take it personal and will never, never discredit anyone's opinion...cause they are entitled to it...

Ed i truly appreciate your insight and knowledge in this area. its people like you we learn from and grow in our passion for this sport/hobby etc...

thanks Bill for your input..i have learned some good stuff from this thread.

brian

[topsportsman1]

Brian

Is this the reason you are talking about the shocks bleeding over into the other part of the chamber?

If so,maybe thats why some of your smart chassis builders or tuners,put the double adjustable shocks on "upside down"?
This inturns keep the fluid on the down side of the shock,so gravity wins,LOL

Is this what you are trying to bring out,and why?I think this will help the bleeding over into the other part of the chamber.

Thats how I got my Afco's,and besides that it is much easier to adjust the "sweeps" for tuning,the clicks are a knob and can be adjusted easily it the top position.

Most race cars are tight,its much easier to do the "sweeps" when they are on the bottom,towards the ground. :P

[bjuice]

YOU HAVE A PM.

Brian

[topsportsman1]

I do?
Never got it :roll:

[bjuice]

check again...the new check box in the top left has caused me to lose a few postings...

brian

[edvancedengines]

check again...the new check box in the top left has caused me to lose a few postings...

brian


Me too. It seems that could have been done a little better or maybe have been put to the bottom near where we click to post.

As long as it takes me to write a post it is really frustrating to lose it. I just give up and quit when that happens.

Ed

[chuxluv]

I will say to some who will listen that the reason some of the shocks have a larger canister is to have more fluid to keep the fluid cool making them work more consistent in certain applications. IMHO :lol: Chuck

[supergass]

My opinion would be that it would be much the same as a piston in a cylinder bore. There is blow by, but compare piston speed to the rate of bleed off is minimal. The shock is maybe the same, in the time the shock takes the hits it takes in a pass the tunability of the double adjustable is effective because the percentage of loss isnt enough to spoil its effectiveness. The shocks I bought for the front of my car (AFCO) double adj. made it a different car all together.

[Bubstr]

I am not a shock expert either. I know there are claims by this one and that, but I heard an interesting conversation about shocks at a big dirt track race. I went down to the pits to visit old friend, who's son has been in the top 5 nation wide for a few years now. They where talking sponsor money and free shocks. What was said by three of the top dirt track racers anywhere was, what ever one that makes the deal is best. If they don't fit their needs, they make them fit. As was said there," you can make a black man out of a Mexican even if they look different on the outside". So don't go by what you see on the top racers car. You would be better off looking at the guy that is in your knowledge bracket to get a good idea what works off the shelf.

[onedragracer]

Dang bjuice, I was going to upgrade to doubles this winter but now I'm confused.

[elkymann]

i have a pretty smart chassis man that has built/dynoed his share of shocks. He steered me clear of the double adjustable shocks..i ask him why?..he advised me that there was NO WAY that the bleed over from the compression and rebound could be seperated in one canister as the double adjustable shock is designed....although the claims are made that it can be done by the manufactures, he advises that unless there is a independant canister there is no way both compression and rebound can be accuratley (seperated) attained from one cylinder....i went to the BIG BOYS (NHRA SOUTHERN NATIONALS) race last week and looked under several of the BIG name cars such as Greg Anderson etc...low and behold i saw double adjustable shocks but with a independant canister with remote wiring (NONE of the Double adjustable stuff being sold as we know it)....i do not know what brand they use cause i could not get close enough..( i assume they have them custom built or something to that degree) but i will list a few brand name manufactures that build these shocks..they are the TRUE double adjustable shocks and they are very HIGH PRICE...
Now i AM NOT trying to steer anyone away from buying a double adjustable shock..its your money do with it as you will..i just wanted to give you the side of a true double adjustable shock that the manuafactures will not tell you...I personally have single adjustable shocks and will not touch the SO-CALLED double adjusteble shock for the reason i am stating in this thread..its a waste in my opinion. here are a few brand names and a little literature from one of the sites..PLEASE DO YOUR OWN RESEARCH BEFORE YOU GO PAYING FOR A DOUBLE ADJUSTABLE SHOCK..."Get what you pay for" AND BE YOUR OWN JUDGE !!!!!!.......

( THE ABOVE IS MY OPINION ONLY. IT IS NOT INTENDED FOR NOTHING MORE THAN A PERSONAL OPINION !!! )

#1- OHLINS #2 BILLSTEIN #3 PENSKE....

below is some info from the OHLINS site on the introduction of this shock.


Introduction
The TTX damper is the culmination of three decades of Öhlins’ successful participation in world championship events winning more than 100 World Championships. Many years of work together with some of the world’s most successful racing teams together with advanced dynamic analysis methods developed at Öhlins Racing headquarter in Sweden has given Öhlins the unique knowledge needed to design the TTX damper.

The Öhlins TTX damper, originally developed for formula racing, is designed to handle the demanding damping characteristics needed for all types of tracks, from street courses to super speedways

The TTX damper is fully adjustable with maximised damper response together with qualities you’ve never seen before when it comes to "settings".

Low and high speed compression and rebound damping are externally adjustable and fully independent. The adjustment range is huge with equal increments of force throughout the adjustment range. Even the shape of the damping curve can easily be changed. All adjusters affect the flow from the main piston, not the piston rod displacement volume.
Some classes may need the TTX 40 with 3 or even 2 adjusters. For this puropse there is a needle housing that uses the existing parts in the 2-way adjuster and transforms it to be a 1-way adjuster suitable on either compression or rebound or both. Part number for this needle housing is 05953-03. Preload changes is made by adding shims on one or boths sides of the coil spring. Shims that should be used in the 1-way adjuster are: 00610-16, 00615-16,00625-16 and 00630-16.

The compression damping forces of the TTX damper are not, as in a conventional damper, caused by a pressure drop on the rebound side, but by increased pressure on the compression side. This reduces the risk of cavitation and makes any reservoir valve or high gas pressure unnecessary. So, no balancing of reservoir damping to main piston damping is needed to avoid cavitation and improve damping response. Maximum response and minimum risk of cavitation will always occur. With no reservoir valve, the internal pressure of the damper unit will be kept to a minimum. The low amount of hysteresis results in excellent short stroke/high force performance. Also, a very low gas pressure can be used without any loss of damping performance.

Along with the damper comes a unique Valving Reference Program (available for download free of charge at www.ohlins.com/Automotive/Products/FormulaSportscar). This computer model of the damper will allow you to find damping curves without a dynamometer. It will reduce building time tremendously and allow exact damper adjustments in pit lane. The TTX product will revolutionise the work for mechanics and engineers in the racing business.

This manual text is based on TTX dampers starting with Öhlins part number TTX NE0. These are through rod type dampers loaded with several new concepts. As always, all dampers are tested before they are delivered to the customer. In keeping with Öhlins long tradition of perfection, quality is outstanding and long life is to be expected.

Welcome to the World of Öhlins.

Design Criteria
After the Öhlins TT44 was introduced to the market in 1996, it very quickly became one of the most popular dampers in formula racing. For some period, more than 95% of the cars in The Champ Car World Series were using TT44 dampers.

There are several reasons why the TT44 became so popular. One reason is that it came with some new features not available on other dampers. One of them is the powerful low speed adjusters, totally independent and with the compression adjuster restricting the oil flow from the main piston, not only from the piston rod displacement. Another is the compression high speed adjuster, giving new possibilities to reshape the compression curve.

When designing the new TTX, the goal was to come up with a damper which would be just as big a step forward as the TT44 had been. Highest priority should be not only to design a damper with excellent performance, but also a damper easier to work on and use than any other product available.

During the development several patent applications were made.

Six of the most important design criteria for the TTX are listed below.
1. No reservoir valve
The damper design should be with no reservoir valve. In dampers where reservoir valves have to be used to avoid cavitation, one more parameter has to be optimised – the right amount of reservoir damping.

The hysteresis will be minimised, as no reservoir valve has to be used. All damping comes from the pressure drop over the main piston. Damping forces from a reservoir valve always causes more delay in the damping force build up. See chapter Hysteresis for more information.

Using reservoir valves always increases the internal pressure. The friction from the piston rod seal/seals can be kept low because of the low internal pressures.
2. Main piston flow
Another criterion was to have all the adjusters regulate the flow from the main piston. This will give the maximum pressure area and because of this, the maximum oil volume to regulate.

The larger the pressure area is, the lower the internal pressure will be for a given damping force. The lower the internal pressure, the less flex there will be. The flex is caused by expansion/compression of the damper body and compression/expansion of the oil. The result is excellent short stroke/high force performance.

With a large volume of oil passing through the valves , it becomes easier to control the restriction of the oil. In other words, the matching of dampers will be improved.
3. Full adjustability
On the TT44/TT40, it was never possible to use a high speed rebound adjuster in combination with a high speed compression adjuster. On the TTX, we wanted to be able to combine those two while keeping them completely independent from each other, as with the low speed compression and rebound adjusters.
Poppet valves preloaded by coil springs were picked to become the high speed valves, as they can be made very compact in size and precise in opening pressure. This type of valve very often gives an abrupt opening characteristic, resulting in a sharp "knee" in the damping curve. To make the "knee" more rounded and to be able to change its shape, some shims are added to the face of the poppet valves. By changing these shims, the shape of the "knee" can be affected.
4. Simple valve changing
Even if the adjustment range of the external adjusters is huge, sometimes there might still be a need to change the valving of the dampers. In other words, change one or several of the following parts: poppet valve/valve seat, coil springs and nose shims. As this very often is done at the track and has to be done quickly, this job has to be simplified as much as possible. Compared to reshimming a conventional damper, any of the changes in the TTX will be a lot quicker. The result exceeded our demands.

Also it should be possible to fill the damper without a vacuum-filling machine, as this otherwise would be a limiting factor.
5. Through rod damper
A through rod damper has some technical benefits. One is packaging, which is a main issue on formula cars. The reservoir volume can be very small, as there is no piston rod displacement. Here no external reservoir is needed. Also there is no gas force pushing the piston rod out of the damper body. (The word "nose pressure" is sometimes used for this force.) Here the nose pressure is zero. This has several advantages. The nose pressure doesn’t vary due to temperature changes and you don’t have to fight the gas force when installing the damper on the car or in the dynamometer.

Designing a through rod damper gives the possibility to separate the rod bushings and keeps the distance between them constant. If coilover springs are used, the amount of friction will be tremendously reduced.

As the piston area for compression and rebound are identical, the damping forces will be the same if the same valving is used and the adjusters are set the same. To some degree, this simplifies the use of the damper.

For all the above reasons, race teams have been interested in through rod dampers. Also, when introducing the TTX, we wanted it to be something very different from the other products out on the market.
6. External clocking
Another strong side of the TT44/TT40 was the possibility to clock the reservoir bracket at any angle. This function we wanted to keep on the TTX damper, to ensure an optimum installation on any car. Just as on the TT44/TT40, the clocking of the adjusters on the TTX in relation to the top eye should be possible to change without opening the damper.


Beetle, your so cool with all your toys, I thought I would give some advice I heard and read about AFCO shocks, they have a double adj. shock that is independent of each adjustment from compress. to extend, so check them out. I feel, imo, THE DOUBLE ADJ. shock is the BEST shock type to get, yeah, a little more tuning to do, but once you have an understanding of the shock, spring and balance of your chassis, you will believe me in the mentioning of AFCO shocks. They cost a few bucks, but do your homework, and look at what NHRA pro stock cars run, they are the Ultimate in racing tuning for a door car, so follow there lead as they have done all the homework before you. My 2 cents. How you doing by the way??? :D I have ventured into Motorsportsvillage.com from time to time and forget to come home once in a while to RJ.....

I am saving for a backhalf for my Elky as the 10.5 tire was getting punished wayyyyyy too much, wish I knew about the stiff sidewall tire a while back!!! :( This seems to be the tire of choice regardless of what power level above 700hp. food for thought for you, run the stiff sidewall tire on your toys, and I know you have the power toys buddy :D

Stay in touch would ya, your a cool racer and how's the family doing? What do you have left as far as race cars????? I think I saw that you sole the vette???

Elkyman John