Routing PCV system into the exhaust

[jdub]

And how much of the time is your motor in boost vs just good ole cruise?

The 18-20 inHG this motor pulls for 85% of the time most of us drive is far superior to the vac source from the accordion hose or from what can be achieved at the downpipe.

I have a hard time understanding why anyone would want to do this on a street car :3d_frown:

 

[MK3Brent]

And how much of the time is your motor in boost vs just good ole cruise?

The 18-20 inHG this motor pulls for 85% of the time most of us drive is far superior to the vac source from the accordion hose or from what can be achieved at the downpipe.

I have a hard time understanding why anyone would want to do this on a street car :3d_frown:

Right, I understand this setup works most efficiently at WOT scenarios. Only.

 

[c_ronius]

No slash-cutting for wesbeech :momaru:

I know a decent amount about venturi action (for water systems anyway). There has to be some sort of a special cut (slash) in the pipe for it to venturi and create suction. Or a combination of a slash cut and the proper angle into the main flow pipe. Those seem to be just welded in at a 90 degree angle to the exhaust, and if there is just a straight cut on the end of the pipe in the exhaust, I really dont see that pulling any vaccuum at all. If anything, I'd bet those check valves just stay shut 100% of the time. Have you ever put a vaccuum gauge on there to see if it actually pulls vac? Not trying to be an arse here, I just don't see that actually working, and I'm curious if there's more than meets the eye.

 

[Nick M]

Wow! So you got rid of the ECU and oxygen sensor?

You are awsome with your posts.

His problem is already pointed out. It pollutes unecessarily.

 

[supraguru05]

And how much of the time is your motor in boost vs just good ole cruise?

The 18-20 inHG this motor pulls for 85% of the time most of us drive is far superior to the vac source from the accordion hose or from what can be achieved at the downpipe.

I have a hard time understanding why anyone would want to do this on a street car :3d_frown:

maybe i should have specified this is for my race car. that gets trailered to the track. i was worried that even at the track it would not pull enough vacuum to help the piston rings seal and keep the front seals happy

heres a link to the slash cut i ordered
http://store.summitracing.com/partd...7810&N=700+400105+4294821957+115&autoview=sku

 

[jdub]

Makes a *tiny* difference

 

[Nick M]

If it is for the track, get a crank case vacuum pump from Summit Racing.

 

[supraguru05]

by track i mean road course lol. i dont know if i would trust the electric vacuum pumps to not give out does anyone have any experience with them plus that just adds more weight and wiring. ill definitly look into them tho

edit these are what i found on summit if your talking about something else let me know

http://store.summitracing.com/egnsearch.asp?N=700+115+%2D57060&D=-57060

kinda pricey i know you have to pay to do stuff right but i would rather put that 300 bucks elsewhere for now ill keep the tb vacuum just for reference what kind of crackcase pressure are acceptable

 

[MrWOT]

^ Cheap alternate is available. Modified Ford smog pumps to handle oil mist and run those for a light vac, are available and quite successful. Routing to inlet with a good catch/mist seperator is just fine for most setups, but a vac pump does have a number of benefits if you wanted to go that route. The lower pressure in the crankcase means there is less air for the pistons/rods to displace every revolution, and it also helps the rings seal. Usually, you'll show a gain in power, enough to offset the drag of running the pump.

edit: for serious track use, dry sump if possible

 

[supraguru05]

^ Cheap alternate is available. Modified Ford smog pumps to handle oil mist and run those for a light vac, are available and quite successful. Routing to inlet with a good catch/mist seperator is just fine for most setups, but a vac pump does have a number of benefits if you wanted to go that route. The lower pressure in the crankcase means there is less air for the pistons/rods to displace every revolution, and it also helps the rings seal. Usually, you'll show a gain in power, enough to offset the drag of running the pump.

edit: for serious track use, dry sump if possible

haha yea dry sump has entered the mind but its not a cheap option ans since the 7m is merely a engine to hold me over until i get a 2j ill probably just wait till the 7m lets go. right now im only hitting a road course once a month and one or two autocrosses a month

 

[Dutch7m]

and what would be the best pcv setup for a high power street car?

 

[supraguru05]

and what would be the best pcv setup for a high power street car?

probably a electric vacuum pump as discussed earlier

 

[Dutch7m]

probably a electric vacuum pump as discussed earlier

has anyone on here done this before on a supra?
ive bin looking around for it and this is the most interesting articel i could found about it,
http://www.highperformancepontiac.com/tech/hppp_0703_pontiac_evac_pump_kit/index.html