HELP: Does the carb'd GTS motor use vaccum for crank case venting? Do I have to?

[Cobra4B]

I have my car at a local shop getting the valve-train allignment fixed (isky adjustable guidplates) and I asked them to weld fittings to my valve covers to mimic what the GTS car has on Panoz's website. I dropped it off this morning and when going over the work to be done they're suggesting that the car needs a vaccum source to maintain negative pressure. Now I know that a vaccum pump or a vaccum source is optimal, but is it really needed. This is a KISS car and It only sees the trailer and the race track. I change the oil after ever weekend anyway.

Thoughts? Do I really need to have them plum into the intake to draw a vaccum or can I just run a line from each valve cover to the catch can as planned?

For reference here's the GTS motor pictured:



Big version can be seen here by clicking on it: http://www.panozauto.com/EsperanteGTSDetails.htm

My motor...



The composite valve covers just had breathers on each one, but that made a big mess.

[wirewheel99]

Our Purple GTS vents to a catch can with a breather on top..

[Cobra4B]

I'm having them set it up like the GTS picture on the Panoz website.

[NZGTRA17]

Originally Posted by Cobra4B

I'm having them set it up like the GTS picture on the Panoz website.

Brian, the vacuum set ups that I have seen are used more in drag racing than on circuit cars. The exception is where you are running a dry sump on a circuit car.

Question really is, do you have a breathing problem now? If not I would stick to just using a decent size catch can (we must use one of at least 2 liters volume for engines of 5 liters plus capacity). I have set my catch can up so that it has a drain line going back into the pan via the spare fitting adjacent to the dip stick. This means that any oil that is pushed out into the can drains back to the sump making the system closed loop. I have also plumbed in a line so that oil can be added to the engine via an external fitting without removing the hood. This oil drains down into the sump via the same catch can return line.

If you are putting fittings into your rocker covers, use a decent size like
-12. Reason for this is the bigger the diameter the more you reduce the velocity of the air moving in the hoses which cts the amount of oil carried by the air. I used -10 and regret that I did not use -12.

On another note Brian, I have a (used) 347 shortblock on its way. Eagle forged crank, JE pistons etc. Will put this in car slow time and use with current bits I have. Looking for around 380 - 400 rwhp and 370 - 380 rwtq. Will let you know how it goes.

Kel.

[Cobra4B]

Thanks for the input Kel... I'll touch base w/ the shop on the size of AN fittings etc.