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Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 8:54 am
by RDY4WAR
Would the benefits of an exhaust sourced crankcase evacuation system be realized on an OEM stock engine with stock rings/tension/gap? I'm wondering if there would be any benefit at all (even 1 hp), not whether or not it's worth it.
Engine: '93 LT1 350ci stock engine with just bolt-on modifications trying to squeeze every last 0.5 hp without opening up the engine. Dragstrip only.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 2:17 pm
by engineguyBill
Crankcase evacuation system will not add any torque/horsepower at all in a stock engine application. Just make sure that your PCV valve is working correctly, that is about all you can do regarding this issue.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 3:12 pm
by Kevin Johnson
If you are able to draw a depression, the windage and pumping losses will be incrementally lower.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 7:34 pm
by cardo0
The exhaust operated CCV system will only be effective at near wide open throttle. You can find a video or 2 on U-Tube that show the results on a street motor. At low rpm and high manifold vacuum you need a PCV valve and carburetor or EFI tuned to match it as the exhaust won't pull enough vacuum at lower exhaust flow. For some reason the big cammed motors with a lot of overlap cause problems for the idle circuit of the carburetor/EFI as the PCV opening rates no longer match what the carb/FI needs.
For a street motor your gonna find your searching for a PCV valve/system to work right with a big cam. Yes your car is now an experiment. Have fun with it.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 7:47 pm
by Kevin Johnson
RDY4WAR wrote: ↑Wed Jul 29, 2020 8:54 am
... Dragstrip only.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 7:52 pm
by Kevin Johnson
RDY4WAR wrote: ↑Wed Jul 29, 2020 8:54 am
...
Engine: '93 LT1 350ci stock engine with just bolt-on modifications trying to squeeze every last 0.5 hp without opening up the engine. Dragstrip only.
Do you consider headers a bolt-on modification?
viewtopic.php?t=59218#p836083
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 8:05 pm
by SpeierRacingHeads
I'm getting ready to add this to my street car. Have a few customers that say they work great. Can only expect 4-5" @ 12.5 volts. More with more. I'm going to run it through the PVC.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 9:30 pm
by BOOT
RDY4WAR wrote: ↑Wed Jul 29, 2020 8:54 am
Would the benefits of an exhaust sourced crankcase evacuation system be realized on an OEM stock engine with stock rings/tension/gap? I'm wondering if there would be any benefit at all (even 1 hp), not whether or not it's worth it.
Engine: '93 LT1 350ci stock engine with just bolt-on modifications trying to squeeze every last 0.5 hp without opening up the engine. Dragstrip only.
Are you pushing oil past your seals/gaskets?
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 9:34 pm
by bentvalves
SpeierRacingHeads wrote: ↑Wed Jul 29, 2020 8:05 pm
I'm getting ready to add this to my street car. Have a few customers that say they work great. Can only expect 4-5" @ 12.5 volts. More with more. I'm going to run it through the PVC.
who makes that unit? looks OEM.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 10:02 pm
by turbo camino
2006 Taurus, I believe.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 10:29 pm
by Bwh998
I've been looking at this one, for Ford Transit vans.
https://www.oreillyauto.com/detail/b/st ... ump&pos=47
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 10:39 pm
by bentvalves
how do those vac pumps respond to oil getting spit up into them?
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 10:46 pm
by Bwh998
bentvalves wrote: ↑Wed Jul 29, 2020 10:39 pm
how do those vac pumps respond to oil getting spit up into them?
I'd assume not well. I'll use some kind of separator if I wind up installing one.
Re: Crankcase Evacuation System on Stock Engine
Posted: Wed Jul 29, 2020 11:36 pm
by turbo camino
They are the same design as a vacuum cleaner motor. A centrifugal blower optimized for generating low inlet pressure rather than high outlet pressure. The only problem oil or any liquid would cause would be down to whatever they use for the shaft seals.
Re: Crankcase Evacuation System on Stock Engine
Posted: Thu Jul 30, 2020 12:48 am
by ptuomov
RDY4WAR wrote: ↑Wed Jul 29, 2020 8:54 am
Would the benefits of an exhaust sourced crankcase evacuation system be realized on an OEM stock engine with stock rings/tension/gap? I'm wondering if there would be any benefit at all (even 1 hp), not whether or not it's worth it.
Engine: '93 LT1 350ci stock engine with just bolt-on modifications trying to squeeze every last 0.5 hp without opening up the engine. Dragstrip only.
If you have headers, a well integrated vacuum port in the collector, and open pipe without mufflers, I don’t see any reason why it wouldn’t pull a vacuum. And if it pulls a vacuum, in principle you can use it to lower the crankcase density and that will improve the engine power a little bit at high rpms. Whether the improvement is large enough to measure is a separate question.