Crankcase vacuum with mufflers?

[bigbluedodge]

Looking for anyone with experience on this:

I've been running a mild 499 stroker (racing only) for years with open headers and the crankcase vents run to the collectors for vacuum. If I put mufflers on these headers how much will that mess up my crankcase vacuum?

Bry

 

[Darter6]

Depends on the type. Race Bullet ? Reverse flow like a turbo muffler ? Full exhaust ?
Race only ? If race only then Vac-u-pan with a race bullet for classes requiring mufflers will be fine.
EDIT The above statement is with the muffler at the collector flange.

 

[topside]

On my car, we had to add some kind of muffler (91 db rule) and my pan-evac didn't work well with them.
System was 3.5" pipe, X, race bullets, ended at rear axle.
Got a GM electric vac pump (cheap, used; found on Vettes, Camaros, etc) & catch can w/breather and plumbed it using a valve cover cap.
Wired through a relay, whole system weighed maybe 5 lbs or so.
Put a nipple on the other valve cover to measure vac and it measured 5", which works great for the car.
(Low-10s 368" SB Duster, regularly sees 7500 RPM.)

 

[bigbluedodge]

Thanks for the responses. I think I'm going to go with cheap 9" straight thru mufflers hung on the back of the header and end it there. If that gives me trouble, now I have another idea.....an electric vacuum pump. Thanks again for the advice!

Bry