Pan E Vac's
 

Has anyone tried a with and without on the dyno or an A/B at the track to see if it actually is worth anything on a S/S engine. I know there is something with a vacuum pump, but is it worth the hassle to plumb it in a already tight space? Thanks, Dyno

Re: Pan E Vac's
 

We tried a vac pump on a gt car several years ago did not make one bit of difference. Never tried it on the track.

Re: Pan E Vac's
 

It's the ring package/tension that you can run that makes the power, not the vacuum itself. The vacuum allows you to run the trick rings.

In any case, vacuum should help ring seal and reduce blow-by overall, so even pulling a little vacuum from the exhaust flow should be useful, regardless of whether or not there is any immediate power advantage to be seen on the dyno.

Re: Pan E Vac's
 

The blow back under the car is messy but you won't worry about rust.

Re: Pan E Vac's
 

Back in the day somebody did a lot of work on tube placement, openings and what not. With his car on jack stands he had the hose in a pan water and had it set up so fine it would empty the pan in no time, took it to the track and it was worth nothing. Save it for something else. Been on here before but a pvc system showed something, just remember all that air that we try to get into the top of the engine with trick carbs intakes and cly heads is moving under the piston and the better we control it the better it makes the oil and HP. But you still need a good ring package. Tom

Re: Pan E Vac's
 

I was down 9 h/p on the dyno with my 350-255 super stock engine WITH pan evac...in the trash it went...Luke

Re: Pan E Vac's
 

I know in theory it should be worth something, on my car it shows nothing either way. I need new headers built and I am sorting things out. thanks, Dyno

Re: Pan E Vac's
 

We went back to back on the dyno about 3 or 4 years ago. Nothing fancy, just tubes in the collector tied to the valve covers. This was a 440 SS motor, made 6 hp no changes. Made two pulls that were identical. And we just always run them in SS.

Re: Pan E Vac's
 

Did anyone use a vacuum gauge to make sure you were pulling vacuum? It takes time to seal all the leaks and if it's set up right, you can pull nearly 5 inches. It's worth the effort.

Re: Pan E Vac's
 

Have done A-B-A testing on many types of engines, always worth 5+ hp. Connecting vacuum gauge on dyno is very important to affirm gasket sealing. Can pull 5" on a nothing fancy system. Have heard as high as 10" achievable with some work. Smoke machines very helpful, especially on vacuum pump engines to find pesky vacuum leaks. If it has vacuum leaks, it will not create a vacuum. And the obvious...ring package and ring seal always play a big part in the effectiveness.

Tom Hestness