vega launch.....

[mwbrasher]

i have a 74vega... last year we had the car back half... 4 link... 5:13 gears...coil overs...14x32 tires... this year we had the front end re-done... tube frame mustang ll suspension.... coil overs etc..... took the car out last nite for test&tune... pulled l-front tie about 2 feet in the air... r-fr0nt was only about 8" off the gronnd... 60 ft time is 1.53... with all the chassic work done... should'nt both front wheels be the same height off the ground?? any advice would be great... thanks caveman :? :? :?

[fla1976]

Does it have frame connectors? Does it have a 8 point roll age? Shouldn't be twisting up like that.

[fla1976]

Here is a photo of my old Vega, it is pretty level. Frame connectors and full cage. It stiffens the frame significantly. It was a low budget car and ran 10.70's. Not the fastest, but I had less than 10k in it.


http://imageshack.com/a/img51/8697/pcv8.jpg (http://imageshack.com/i/1fpcv8j/)Uploaded with ImageShack.com (http://imageshack.com)

[mwbrasher]

yes... has 8 point cage... motor plate in front and rear...chassis cert to 8.50... thanks for responce... "i am confused" over 8 grand in chassis work!!!!!!!!!!!!

[fla1976]

Sounds like a similar setup. Ladder bars, Ford 9 inch with 4.88 gears. 11.5 x 30 inch tires (Not enough clearance for bigger tires. Front and rear motor plates. Engine set back to #1 cylinder aligned with front spindle. 60 foot was usually around 1.46
There is way too much flex for what has been done to your car. If you jack up the left front with a jack about a foot, does the right side stay on the ground? It sounds like some serious twisting.

[TheYellaBrick]

Well don't fret over the monetary amount in your chassis. NOW is the time to be LEARNING how to 'tune' all that adjustability. :-)
Need to spend a day or a few evenings and set the car up to a 'base line' setup. Square the front and rear axle lines, corner to corner/side to side front to rear. Write EVERYthing down in a log book. When at the track, make ONE small adjustment at a time. JUST ONE. write it down, and also note what the change did in how the car felt or reacted. Making any more than ONE adjustment at a time will get you so lost off the base line you'll never get it back, except back in the shop.
We've discussed this very subject a few times here on RJ, so I know we'll be able to head you in the right direction.
Chassis twist under violent launches can be reduced by increased tire pressure on right rear, stiffer shock setting on RR, some 4 link adjustments.
You might shoot us some pics of the cage and rear suspension. Pics ALWAYS help !
A properly built cage will turn the chassis into a 'gerder' type bridge, VERY stiff.

[markdunlap]

For $8K chassis work, it should have included an anti roll bar in the rear that would eliminate the twist at the launch.

[mwbrasher]

thanks for the information... there are so many adjustments... i guess i need to start from square one... i will let you know what i find...thanks again...caveman

[itsabird]

how about some pic, of your 4-link set up with the slick off.

[fla1976]

I am trying to find a copy of the chassis information from Ed Vance. He has passed but he gave a lot of info in one of the threads on chassis setup. I will try to locate it again. It was on an older computer that died and I have it saved somewhere. Great information.

[fla1976]

Mwbrasher, check your PM, I found the info.

[TS1955]

For $8K chassis work, it should have included an anti roll bar in the rear that would eliminate the twist at the launch.

X2

TS1955

[mwbrasher]

thanks guys for the info... will give it another go on fri nite!!!!!!!!!!!!!!!!!

[mwbrasher]

well we went to thunder valley last nite... car went 6.97 in 1/8.. at 97.6... had a un known person from down there look at my car... he had a ply arrow.... sort of like my car... any way.. he came by... looked at my car... you need more bracing... from the top frame to rear around where belhousing goes.... i said no way... we jacked the l-front of the car` about 42 inches of the ground... r-f was still on the ground.... went and looked at his... sure enough.. he had those bars... his pulls both font wheels the same.... thanks every one... i,ll fix mine and let you know how it works...thanks caveman......... :D :D

[TheRabbit]

I'm not familiar with 8.5 cert ( it may cover all of this + some) but an; anti roll bar, x brace under the car, x brace in the doors and support bars from the motor plate to the snout bars will keep it from twisting.
A lot of people overlook the motor plate bolts too. 2 bolts will allow the frame to pivot. 4 bolts (2 each side) will help stiffing it up a good bit.

[melson3086]

Have you contacted the builder and had him look to find out where this supposed twist/flex is coming from? And to clarify you had one tire 42" off the ground and the other was not, Thats better than most rock crawlers? Pic's please!!

[mwbrasher]

yeah pat ..i talked to you... but i guess your to busy... but thats ok... i'll fix it my self... i can weld to...

[melson3086]

yeah u never said nething was twisting /flexing you just said one tire was lifting higher! Did you load the bar i told you to? and if so how much did it help? But with the amout of twist your saying it has it would have fkd up the fire wall or riped out the trans mount bolts or shown its self some where and if it was twisting how is it going back the same ever time, does it twist the same foot braking the car as trans braking? I TOLD you once you have it complety ready to go to the track bring it by and i would set it up and have you ever brought it by for that? And yes i have been busy ive worked the last 20 days straight 12hrs a day! I was told by a birdy that your car leave flat as a board off foot brake no twist! Im just saying I would love to see this twist you say it has and if it is twisting as you are making it out to b just two bars vertically like you say will not fix it! Ill come over to see it tomorrow "saturday" after i wake up and you can show me it if you have time ill be up at 2pm and gota be back at woke at 5pm! SORRY for all the back and forth questins!

[bigray]

mine is a 2008 Suncost Corvette, with a 8.80 cert. I just jacked up my front end, at the drivers side control arm, and maxed out my jack and never lifted the pass side wheel off the ground, with the flex you say you have, Rock Crawlers don't even have that much, and your fire wall is not crinkled. or show any signs of binging flexed ? hummmm.. I checked on the Wallace racing calculator. ( Your 1/4 Mile ET is 10.95 seconds computed from your vehicle 1/8th ET of 6.95 seconds.
Your 1/4 Mile MPH is 121.52 MPH computed from your vehicle 1/8th MPH of 98 MPH. ) heck that's not bad at all for your motor, it was like a 9.5 to 1 . But I know we are talking about Flex. not H.P. I bet it just needs some tuning in the rear bars,

[mwbrasher]

hey ray... doesn't your car have a square frame.. and isn't it stepped up to make car lower?... there just alike... only different.....

[mwbrasher]

hey pat... your little birdie was right... down in okc... foot brake only... could only leave at 2300 rpm... or car would move... yes... it does not pull the front like with trans brake....i waited for you this after noon... guess you were busy....
oh well see you later.

[bigray]

ummmmm. never said they were just alike, I was just telling everybody what I had. and yep. its a 2x3 main frame rail car with a 4 link, and I did jack mine up as far as it would jack up.and it flexed the 4 LINK bars and never lifted the pass wheel. heck I even had the drivers side rear wheel also most off the ground. and the pass side was buried in the wheel well. no frame flex just 4 link movement, I Really think you need rear end set up tighter,

[melson3086]

never head nething from ya so im not gona travel up there for ya to maybe be there! But sence some jo blow said to weld two bars vertical then i guess get to welding sence you know how to weld also!

[melson3086]

Also to clarify you didnt pay 8k for chassis work! But you may have 8k in your chassis!

[mwbrasher]

already welding... ...thanks for your help....

[AR3366]

Not my deal here guys.. But in the professional world when something gets paid for.. It's for a complete correct doesn't need stuff fixed or added on or redone type of job. And if there is a problem the builder doesn't act like its an inconvenience, IE you didn't call me and what not.. They would take the steps to do WHATEVER it took to make things right. That's why money changed hands to start with. Understanding Business ethics, one would bend over backwards to fix things cause other wise that's bad ethics and not consistent with positive future events- ie getting more jobs based on quality work via word of mouth. Just my .02 .

[bigray]

(AR3366 ) believe me, there is alot more to this story, we all live here in the same area. so you would just have to meet with the car owner to get the full picture,

[TheYellaBrick]

In that case , gentlemen, I'd advise you to take it to a private conversation via PM/email/ or whatever. We're not interested in local 'spats' and tit for tat's her on RJ. The original post was to glean advise on a particular problem a fellow racer had. Let's keep on THAT, please.

[mwbrasher]

i was looking for more options.....in my openion... the car should not twist... i was not looking for a fight... just more openions... if some people are offended by this.... OH WELL!!!!!!!!!!!!!!!!!!!!

[melson3086]

you are right the car shouldnt twist, untill reading this i never knew you thought it was twisting and im not convenced it is twisting! Thats y i asked so many question in earlier post you didnt answer!

[AR3366]

Is a forum.. So sick of people whineing about what is said... You dont like it you have full control.. Log off, close your eyes... Due something besides complain about others exercising they're civil liberties.. Besides all i said was if it aint right .. Then it should be fixed with out a "fight" cause that is what is right. Hence why at the end i said its just my opinion. That's what forums are about opinions.

[TheRabbit]

I am trying to find a copy of the chassis information from Ed Vance. He has passed but he gave a lot of info in one of the threads on chassis setup. I will try to locate it again. It was on an older computer that died and I have it saved somewhere. Great information.

Looks like you found it, but I have a copy of it if you ever need it.

[TheYellaBrick]

In that case , gentlemen, I'd advise you to take it to a private conversation via PM/email/ or whatever. We're not interested in local 'spats' and tit for tat's her on RJ. The original post was to glean advise on a particular problem a fellow racer had. Let's keep on THAT, please.

[fla1976]

I am trying to find a copy of the chassis information from Ed Vance. He has passed but he gave a lot of info in one of the threads on chassis setup. I will try to locate it again. It was on an older computer that died and I have it saved somewhere. Great information.

Looks like you found it, but I have a copy of it if you ever need it.


Thanks Rabbit. I found it again. I have a printed copy also. Lots of great info. RIP Ed.

[ballsout1]

i`ve got a chevette back half connectors, bar, no cage... 5000 stall mild street 383.
it was like yours """twisting''' FIRST PASS BUT IT WAS ALL IN THE REAR. its a ladder bar car but some princible's should transfer. (i dont have any 4 link xper eence) anyways the right rear was pre loaded up hard about a 2 inch difference side to side and alot of suspension travel in front was taken out. now its a no hands on the wheel 6.80 / 1.44 60` car.

[melson3086]

i`ve got a chevette back half connectors, bar, no cage... 5000 stall mild street 383.
it was like yours """twisting''' FIRST PASS BUT IT WAS ALL IN THE REAR. its a ladder bar car but some princible's should transfer. (i dont have any 4 link xper eence) anyways the right rear was pre loaded up hard about a 2 inch difference side to side and alot of suspension travel in front was taken out. now its a no hands on the wheel 6.80 / 1.44 60` car.

Ding Ding Ding we got a winner!!!!!! Thats all it needs is some tuning!

[bigray]

SOOOoooo is it fixed ?? , did ya weld the bars in and fixed, ????? or adjust the rear 4 link bars and fixed ????

[mwbrasher]

yeap.... it's fixed...............

[bigray]

CooooooLL. was it the 2 bars you welded in. or adjustment on the 4 link bars, are you going to the midnights on Sat night,

[mwbrasher]

well... we took the car to the duck drags on sunday.... the rolling problem is fixed....now the car pulls hard to the right...almost hit the lights twice... left lane ... adjusted top right bar... seemed to make it worse...got put in right lane... still went to the right....real hard... : maybe too much pre-load.... thanks caveman :? :? :?