vaccum pump?

tim

Registered User
I have always wondered how much power is being lost by the pressure being built up in the crankcase. I know on all out drag cars they use a dry sump oil system and a pump to create negative pressure in the crankcase.houghts on the subject?
 
I thought the pump was used for combustable fumes in the bottom end. I think our little engines still work on the negative side though the PCV system. Your not still driving that thing around in the winter are you? I still wan`t to take a ride in that bad boy.
 
I'm pretty sure that there's power to be had by creating a vacuum in the crankcase. It helps your rings seal better and it reduces the pressure on the backsides of the pistons as they receed into the block. I'm not sure how much power but some. I bought an electric vacuum pump to hook to my pcv system but the pump only pulls about 3lbs of vacuum so I took it off and replaced it with manifold vacuum (which is 0 when you need it most).

Electric or mechanical pumps that create a constant 12 lbs or so of vacuum are pretty pricey.
 
Dan an electric pump or engine driven so we can run a dry sump. I like it. Better ring seal is a good thing., so how do we go about it. an electric pump would have to be really strong.:D
 
Palos height is not that far away. Come over and we will see how far it goes sideways in the cold weather.:D
 
I wouldn't run a dry sump but I do think that a constant vacuum would be good. An electric pump that pulls that much vacuum is around $200. They are on some diesels.
 
I can only speak for myself but less crankcase pressure and bettter ring seal seems like it would be worth $200.
 
I forgot to mention, when I had my electric pump hooked up it sounded likea vacuum cleaner running in my car. :mad: I had it mounted inside the instrument panel.

You would want to mount it in the engine compartment or in the trunk and even then, it may be annoying.
 
I have every intention of going dry sump on my car. Maybe not this year, but it's in the 3 year plan.

Check e-bay and you can find the $2500+ 4 stage pumps available for a reasonable cost. You may just have to rebuild. They are usually coming off NASCAR and dirt track cars.

Moroso has a belt driven vacuum pump you could throw on.
 
Going from a wet sump system with crank case relief to a dry sump system picks up my race motors an average 25HP. The lowest gain that I have EVER seen back to back on ANY motor is 21HP. Again, this is just comparison between wet and dry sumps with aftermarket oil pans. A good oil pan, over stock, will net you around 20HP.

Going to a dry sump system, you can control the amount of oil pressure you want to run, also.

Moroso makes belt driven pumps that run $300-$550 depending on the number of vanes.
 
Back
Top