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-   -   crankcase ventilation (https://www.racingjunk.com/forums/showthread.php?t=31453)

Harbone 12-26-2011 04:15 PM

crankcase ventilation
 
The car I just purchased has a healthy 454 and I think the previous owner was going to make it more drag than street. My intention is all street. He installed valve cover breathers with hoses running down the inner fenders like he was going to hook them to the headers for evacuation but never did. Am I better off just putting some regular breathers on the car or put a oil fill cap on one side and install a PCV valve on the other side? Should it be hooked to the carb if I do or directly to the intake?
http://s3.racingjunk.com/ui/1/64/24535641-812.jpg

zipper06 12-26-2011 06:25 PM

Since the car has mufflers, he couldn't hook them to the headers, I would opt for the vented filler and a PVC oposite side, carb or maniflod doesn't matter, which ever looks cleaner.

JMO

Zip.

gearhead1011 12-26-2011 07:58 PM

If you go with the PCV valve and you're going to hook it to the intake make sure it's at the base of the carb and not on a runner.

Harbone 12-27-2011 04:59 AM

Thanks guys! :D

Harbone 12-27-2011 09:00 AM


Originally Posted by zipper06
Since the car has mufflers, he couldn't hook them to the headers, I would opt for the vented filler and a PVC oposite side, carb or maniflod doesn't matter, which ever looks cleaner.

JMO

Zip.

Zip,
Would I want a "vented" filler? I think that would cause a huge loss of vacuum. This motor runs a 585/585 lift solid roller cam and probably doesnt have much for vacuum anyways.

BEAST477 12-27-2011 03:24 PM

Hey Chris, do you need much vaucum? I see it has manual brakes. Is there still a vaucum modulator on the trans?

zipper06 12-27-2011 07:03 PM

Chris, look at it this way, Brian was running 2 open vents into hoses. All you need to do is keep the pressure from building up in the carankcase and valve covers to keep it from blowing oil out of the valve covers at high RPM's. This will not effect your vacuum since that all comes from the intake part of the engine. The PVC valve may hardly ever open except at high RPM since they are designed to only open when there is a build up of pressure in the crankcase, which is created by blow by in the rings.

Zip.

Harbone 12-28-2011 07:11 AM


Originally Posted by BEAST477
Hey Chris, do you need much vaucum? I see it has manual brakes. Is there still a vaucum modulator on the trans?

Beast there is a vacuum modulator on the trans


Zip that answers my question then, I am gonna change it over to the PCV setup this week.

Thanks for all the input guys, I cant wait to get all the changes done to the car and take her cruising in the spring! I might even have to take her to the track, its been about 4 years since I have been racing.

TheYellaBrick 12-28-2011 08:12 AM

Bone, any road racing tracks nearby that host 'Track Day' events ?
How 'bout auto crossing ?
Those 2nd gen 'maros do pretty well in those type events. Also a lot easier on drive train components and is a TON of FUN !

Harbone 12-28-2011 10:03 AM

DD,
There is a track I believe up by the Joliet dragstrip. The car has a the big front swaybar and the stock one on the rear. I installed the full Hotchkiss setup on my last car and it made a world of difference.

TheYellaBrick 12-28-2011 05:01 PM

Here's a start ;
Note; SOLO is autocrossing;

http://www.scca-chicago.com/pdx/todo_list.html

Scroll down for list of tracks;

http://www.scca-chicago.com/links/index.html

Central Div SCCA;

http://www.cendiv-scca.org/

Good used road racing tires;

http://www.ebay.com/sch/leegrx7/m.ht...&_trksid=p3686

Membership info, read both pages;

http://www.scca-chicago.com/membersh...membership.pdf

chevyart 01-01-2012 03:42 PM

pcv
 
hey zipper.. i think i understood you as saying that you cant run crankcase evac to headers if you run through mufflers. if this is true, why cant you?. i never heard of this and im glad to know this if it is true thanks art

zipper06 01-01-2012 08:22 PM

Re: pcv
 

Originally Posted by chevyart
hey zipper.. i think i understood you as saying that you cant run crankcase evac to headers if you run through mufflers. if this is true, why cant you?. i never heard of this and im glad to know this if it is true thanks art

It's because the mufflers create back pressuse in the headers even with flow thru mufflers. You can if just driving around on the street without taking the RPM'S up but when you do you will find every possible leak that the engine may have, it will even blow oil out around the push in evac connectors on the valve covers. The evac system is designed to work with a vacuum in the headers and you lose that with mufflers due to the back pressure that they create.

JMO

Zip.

TheYellaBrick 01-02-2012 05:19 PM

This is a great thread,
I am running 3" from the collectors to the back bumper with no mufflers but through an 'X' pipe just after the collectors.
Question; Would the exhaust mounted evac system work with collector 'baffles' installed or would they ALSO bump up the back pressure too much?
430 Big Block Mopar turning 5K - 7K at full talk for miles on end.

zipper06 01-02-2012 07:56 PM

There's only 1 way that you can run the header evac system with mufflers or baffles that i know of and that is to install the tubes behind the mufflers or the baffles, they will not be as effective as collector installed without mufflers or baffles, but will work. If you've ever blown air across a glass of water you know it will suck the water out, the more air you blow the more it suck the water out, same theory with the header evac system.
In the old days we didn't use header evac systems we just ran about a 4" tall tubes and breathers, i've run blower motors that way in the 60's. Now aday i run burn down tubes 1 1/4" dia into a 1 gal catch tank with the blown alcohol motor with zoomies, but i run a 1471 on a small motor.
I've got a set of zoomies with evac system plumbed into all 4 tubes on each side but i don't think i will use them. I bought them from my friend up in Oregon with the Willys convertable.

Zip.

JEFF69Z28 01-03-2012 02:27 AM

What about useing 6" straight thru mufflers bolted right to the collector? :?:

zipper06 01-03-2012 12:56 PM


Originally Posted by JEFF69Z28
What about useing 6" straight thru mufflers bolted right to the collector? :?:

I doubt if a 6" straight thru muffler would have any effect on the evac system when bolted straight to the collector. i know that some tracks and some classes specify that you have to run mufflers and those types qualify as mufflers.
A good example is the 66 Biscyne with the 468" motor that i built, he runs on the street with some oval 18" mufflers bolted to the headers and it gets by the law. But he tried to run at Baton Rouge last yrs, spraying a 200 shot of nitrous. The car slowed down to 10. teens, and blew so much oil out it took an hour to clean the motor and engine compartment. Next pass we unbolted the mufflers and it ran 9,77 @ 138 and change. The car is really heavy so the engine is under load for the full 1/4 mi.

Zip.

olds48 02-11-2012 10:35 PM

Another reason for not running a header evac system with mufflers is because of the accumulation of oil fumes in the headers (pooling in the baffles or absorbing in to the fiberglass matting) can cause an expolsion/fire hazard. Anyone else ever heard this? I'm not saying it's 100% true,but it does kinda make sense I suppose


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