I've messed around with this for several months now. As of today, I finished and test drove the Vette. I am completely satisfied. The one thing I can't testify to right now is how long the pump will last. The pump is supposedly built to run on the street (will wear less quickly than for example a Moroso race piece). Here's a webpage I've setup to document what I did:

http://www.diabolicalperformance.com...caseevac2.html

All the details are on the page. I'll say here that I'm excited about it. The engine is obviously making more topend power. The test drive was a blast.

 

Nice web page. And very interesting. I don't understand the better idle, though.

RACE ON!!!

 

read ir before but don't remember why,,,thinkin'

 

For the most part that's just a stock A.I.R. injection pump that doesn't have the inlet at the front of the pump under the pulley. I'm just going to epoxy the opening closed and put together pretty much the same setup.

I've got a stock pump apart now to do the same thing.

 

[QUOTE=CFI-EFI] I don't understand the better idle, though.
QUOTE]

What I eluded to was that the better idle may be due to my "fixing" a vacuum leak that I had, that I had not realized I had.

 

Yup, that's right. GZ Motorsports rebuilds these pumps for this use. I left it to a "professional" who had worked with the pumps before. His prices are good so there was no reason for me to cobble it up myself. If you're able to do the modifications to the pump yourself, mo' par to ya.

 

On my car I ran one breather line to the intake for idle vac and part throttle, and another to the header collector evac kit for WOT.

The part throttle pulls like mad, ~10" on average, sometime way more, and sometime less depending on RPM. And the Evac gets up to about 8" when I rev it up.

The whole setup was around 45 dollars and works great.

Perhaps I got lucky with the angles I had the evac system hooked up on as it has alot to do with the way and how much evac you get. But I can tell you they pull pretty decent. Without a baffle system in the covers, I was actually pulling too much and the oil was getting sucked out that splashed off the rockers.

One thing I never really understood with those vac pumps and the catch cans. How can you have a breather onto the can, and have it pull anything from the crankcase? The air if going to come from the path of least resistance, and that is most likely going to be from the breather. It would be like trying to suck from a straw that has a hole 1/2 way up in the side of it. Perhaps I am missing something cause they all have it.

Good setup you have there. I chinced on mine, but it seems to be working.

Edit: Ok I looked at your setup again and I think the breather is on the "push" side of the pump. Sorry when I just glanced at it the first time, I thought it was on the pull side That makes more sense now

 

got Pic's ?????

 

The reason I didn't use the exhaust scavenging is that when you run mufflers, you'll get oil in the exhaust in front of the mufflers. I also thought the air getting sucked into the exhaust might be a problem with the O2 sensor. If yours is working well with mufflers, then it would be certainly less expensive than what I've done.

 

If your motor is sealed up good "no blowby" you will not have alot of oil coming out of the breather. I only had a problem when I had no "deflectors" inside the valve covers that allowed the oil to splash right into the vacuum steam, which then I got oil traces. Since I put little baffle tubes in, the problem has vanished.

Seem to work pretty decent, adn was pretty cheap too, so if it didn't you really did not loose anything.

As for power though, I have read TONS of stuff on the big guys running evac systems, and the only real gains you will see are when you use a good vac pump like yours on a motor built up with very low tension rings. The less friction = more power. And the average power gains are pretty minimal = 5-10hp on a 700hp motor. my thoughts were it wasn't worth the added money.

If you really had a "plugged" up crank that was building alot of pressure, then I think you would feel/see some nice gains

also keeping a decent vac on the motor helps keep oil leaks a min.

 

Sort of an oversite; I had another page where I had built a setup using an electric pump. On that page I had put all the "theory" and pro's and con's. This page I just focused on the finished product. I'll edit this page later to paste that theory stuff in here too.

 

Ski,,, ???

 

 

please

 

If you and comp are asking for pictures, use the link in the first post. There are about a dozen pictures on that page. That's why I didn't post them in this thread...

 

How did the electric pump setup turn out and why did you switch to the engine driven pump?

 

Guys I don't have any pictures of my setup that I know of. I will have to search around and see what I have.

 

Thanks because i haven't seen the other post, i don't think

 

Interesting stuff. One think I don't understand (and I'm not disagreeing with what you're saying, but curious): How does the crankcase evac system improve ring sealing?

Ben

 

Hey Dave nice progress, first class all the way!