devin mac

iTrader: (2)

yeah, i have been meaning to disassemble the piping and clock my compressor and some other small projects. so maybe this is the fire under my *** i needed.

m2cupcar

iTrader: (5)

Agreed- remove the pcv from the cam cover and vent that port/line to the catch can along with the original cam cover vent. Was it smoking only under boost? Is it smoking now out of boost? Those are some good indicators of damage. But IMO not addressing the crank case pressure is a good route to premature wear that could be a voided. Blow by is there whether you see it or not.

devin mac

iTrader: (2)

i believe i saw the most smoke when i was making a higher load boosted pull, say 5th, and then let off. the smoke really poured when i let off.

pulled apart my piping yesterday after work and didn't see ANY oil in the cold side of the charge pipes, and only a scant bit on the warm side. reached up into the intake mani and there was some crud in there but not like a pool of oil.

we'll see what my compression and leakdown numbers look like, once i get the catch can on and boost pipes rerouted (figured i'd take the opportunity to clock the compressor down, while i was in there :-) )

chucker

iTrader: (4)

Now that I've learned that a PCV valve is more than just a check valve (thanks brain), I've decided to run:

1) a GTX PCV
2) a check valve between mani and PCV
3) and rout the vent line just before turbo inlet, maybe with a catchcan.

So which check valve?

This one is inexpensive and compact but it's only good to 275F and it's homo plastic.

This (search p/n 7775K51) is more expensive (2x the price + freight) but it's brass, it's piston type and it has a viton seat good for 400F. It should outlive the car.

Also, I was thinking of assembling a check valve out of brass pieces like a homemade MBC with a light spring and a steel ball. Should be easy enough but the cracking pressure (vacuum) might be too high and the flow might be too low, plus the thought of the engine possibly digesting a hard steel ball and spring doesn't sound too bitchin'.

Any others you guys can recommend? Experiences?

Thanks

m2cupcar

iTrader: (5)

Run the catch can just to keep the oil out of your entire intake. I got oil in my intercooler and lemme tell ya, it sucked cleaning it out.

The kynar/viton is what the turbo rx7 guys have been using and what I was going to try out. But I agree- the brass valve definitely looks superior.

The_Pipefather

iTrader: (5)

I used the first one to solve my smoking problem (off-boost). Its a very high-quality PVDF material which has a melting point of over 340 F so no worries there. I don't have a catch can BTW and my hotside valve cover vent is plumbed pre-compressor.

At first I used no PCV. but then found out that unlike the PCV, this valve opens even at very high vacuums, thus causing a high idle. Then I put the PCV back, it looks like this now:



Been running for about 500 miles so far and its holding up fine.

chucker

iTrader: (4)

Pipe,

Yeah, that's the exact setup I envisioned. The apparent compactness of the plastic unit makes it look perfectly suited; any longer/larger and there may be a fitment issue...

hustler

iTrader: (6)

Every time I turn around there's another $100 in bullshit I have to buy to get this ******* car running.


Why not run a pcv for each side of the valve cover, then the check valve, straight to the intake plenum? This would eliminate the catch can.

The_Pipefather

iTrader: (5)

its not absolutely required, that's what I gathered from this thread. I doubt you'll have issues when both vents are plumbed right. The way I plumbed mine, the crankcase can vent via the pre-compressor vacuum when in boost; the one-way + PCV side will prevent positive pressure. Off-boost, the whole thing works like the factory intended it to.

johndoe

iTrader: (5)

what's up with putting a check valve in the line to the charcoal canister? Necessary?

hustler

iTrader: (6)

considering how hard I'm going to drive this car at 250whp, its required. With my luck, it will blow the dipstick out immediately and fill the piping with oil. It happened several times on my vr6.

Braineack

iTrader: (62)

I'm glad someone listens to me....well if not listens, is at least as smart (stupid?) as me

johndoe

iTrader: (5)

In an effort to remain emissions compliant while still removing oil from the incoming air I think I'm going to do this, it's essentially the same thing as Brain's idea except instead of VTA there's a line with another checkvalve going to the intake. Aside from the emissions thing might there not be benefit from routing pre-compressor versus VTA? When the line to the manifold is closed in boost only the line to the compressor inlet is available and it is servicing both the breather port and the pcv port, allowing twice the evacuation potential over the stock setup. Plus in boost shouldn't we be seeing low pressure in front of the compressor further aiding scavenging of the higher pressure in the crankcase? edit: thinking about using these check valves http://cgi.ebay.com/Check-Valve-HHO-...1.c0.m14.l1318

rb26dett

I've blown an FE3 dip stick out without boost!! It's required for hard driving period and not required if you are a red light racer/pretty boy/nancy. Enlarging the ally holes as Rob has done on his FE3 is required for the FE3. Even without boost.

m2cupcar

iTrader: (5)

doe- you need two cans to be OE emissions compliant just to keep the Pcv and vent systems separated. IF the pcv shares a can with the vent line, then it can vent to air via the can-to-intake line under pressure (blow by). And when in vacuum the manifold is going to pull air through the cam cover vent line - which will inevitably be easier than pulling through the pcv valve. You could put another pcv valve in the cam-to-can line, but IMO you want a free flowing line available to vent blow by under boost and the valve will just impede venting.

I think Fred is right. Even a normally aspirated car that's driven hard is going to benefit from a catch can. The inside of my showroom stock Miata's manifold was absolutely covered with blow by residue after a few weekends of racing because we could not modify any of that system. That's what running to redline for 45 minutes at time gets you. Add boost to the environment and it's only compounded.

hustler

iTrader: (6)

why is there only 1 pcv? Why not have pcv to both sides of the valve cover, or 1 pcv in the line to the intake plenum with a check valve?

johndoe

iTrader: (5)

yeah, I see what you're saying now. I'll keep the same placement of check valves but keep the pcv and breather independent.

chucker

iTrader: (4)

I understand the value of a catchcan on the vent side to prevent oil in the intercooler, presumably reducing its ability to exchange heat...

But oil residue in the intake mani... Is it really a problem? Is it actually enough oil to increase the possibility of carbon deposits or buggered injectors?

johndoe

iTrader: (5)

i thought the issue was that it fucked with the AFR

jayc72

iTrader: (14)

Adding oil reduces the effective octane of the fuel. More oil, more chance of knock.