Crank case Pressure

[ToMMMaY]

im getting oil blown out of my oil return line from my turbo
and as sirnemises said it could be crankcase pressure hoping its not as from what i read its a bitch.

Anyways What should i be looking into first if it is
Cheerios

[SirNemesis]

Managing crankcase pressure is not difficult. Managing crankcase pressure with emissions legalities in mind is a different story.

Assuming you don't care about emissions. The easiest option is to add breathers to the engine. Weld/tap some barbs onto the rocker covers and put some small filters on them. That will reduce crankcase pressure. Of course that will give you an oily smell, but it is better than blowing out seals and dipsticks.

An engine with less crankcase pressure seals the rings better, which results in more power.

There are some more fancy methods like using an exhaust venturi to suck crankcase pressure. Not a bad system, but doesn't work great with high back-pressure exhaust systems. There are also vacuum pumps, but that is getting a bit more extreme than what is required.

[ToMMMaY]

Managing crankcase pressure is not difficult. Managing crankcase pressure with emissions legalities in mind is a different story.

Assuming you don't care about emissions. The easiest option is to add breathers to the engine. Weld/tap some barbs onto the rocker covers and put some small filters on them. That will reduce crankcase pressure. Of course that will give you an oily smell, but it is better than blowing out seals and dipsticks.

An engine with less crankcase pressure seals the rings better, which results in more power.

There are some more fancy methods like using an exhaust venturi to suck crankcase pressure. Not a bad system, but doesn't work great with high back-pressure exhaust systems. There are also vacuum pumps, but that is getting a bit more extreme than what is required.

Just out of Curiosity
Back when my car was Supercharged i added a 10psi pulley was running on the stock pulley no problems
when it basicly hit 10psi it would drop cylinders the problem was never to be found taking it to many mechanics and dynos
i even spent hours on it myself tried everything

could the crankcase pressure be a issue that would have caused this
heres a video of it

YouTube - ‪Misfire‬‏

YouTube - ‪missfire2‬‏

[SirNemesis]

Crankcase pressure can't cause a misfire. The effects of high crankcase pressure on other components might though, but a mechanic would easily diagnose this. The main effect I'm thinking off is forcing oil passed the rings or back through the intake. If it was bad enough to cause a misfire like that, your plugs would be absolutely chock full of oil and filth.

[ToMMMaY]

guess that problem is still unknown ffs
i basicly changed everything twice and still had it other then pulling apart the engine itself only thing that solved the problem was lowering the boost

anyways ill definatly have to get it looked at

[Avi8or]

Not fuel related is it? Sounds to me like your hitting something almost like 'fuel cut' when the injectors cant keep up with the boost and your leaning out.

Edit: The oil being blown out could just be a secondary issue.

[delcowizzid]

how is your pcv system setup most people just blow boost straight into the crankcase via the pcv and make a hell of a mess as well as blowing out the rearmain seal dipstick etc.i block every pcv valve in every build or fit boost specific PCV's on some of the early vn v6's with a pcv valve thats not built inside the plenum LOL.you can block the internal pcv valve and run a boost suitiable one on a rocker cover instead and a small filter on the other rocker cover to let air in

[vc81]

where do you get the the boost specific PCV's delco?

[delcowizzid]

you can buy them for buick from the states PCV or goto pickapart and get an inline style one out of a turbo car try get a metal one not plastic even the one way valves to the brake boosters on turbo jappas work very well

[ToMMMaY]

how is your pcv system setup most people just blow boost straight into the crankcase via the pcv and make a hell of a mess as well as blowing out the rearmain seal dipstick etc.i block every pcv valve in every build or fit boost specific PCV's on some of the early vn v6's with a pcv valve thats not built inside the plenum LOL.you can block the internal pcv valve and run a boost suitiable one on a rocker cover instead and a small filter on the other rocker cover to let air in

At the moment i haunt touched anything with the Pcv i can't just wack a filter on my oilcap cause of the rev plenum and cooler piping so I' most probably will have to modify the rocker covers or so see how it goes

[delcowizzid]

take some pics as one hose goes directly into the crankcase with nothing at all stopping airflow and will really fill the crankcase with boost.and the pcv valve you have to take the upper plenum off the runners to get it out

[ToMMMaY]

Will do tomorrow for shure my fkn engine bay is raped with oil FFs lol be good to
Fix this shit before I get it welded so
I know it's gone then can sort the tune out this week

[delcowizzid]

make sure the pcv inlet hose to the throttlebody is not on the throttlebody any more it fills the crankcase more than the actual pcv valve when they leak.

[ToMMMaY]

So I just block the throttlebody side off and leave the other side venting?

[delcowizzid]

well thats where it gets tricky LOL as soon as you take that hose off the TB you will get a heap of air get sucked into the engine via the PCV valve that the MAF sensor hasnt seen but yes block the TB off and that hose fit a filter on the end of it and block the pcv valve in the manifold. if you still have that hose on thats whats making you have a mess LOL all your boost is going into the sump fast LOL you wont know the car when thats blocked off it will hit boost hard and way earlier

[ToMMMaY]

I think I love you lol I'm running no maf tho lol msg makes me run to rich and stalls on the turbo surge lol should be getting my tune
This week tho

[delcowizzid]

the maf needs to be before the TB after the cooler it works fine setup like that good for 10psi/300rwhp

[ToMMMaY]

Ok btw where is the best place to put the iat in the cooler piping or plenum im just running it off my dose pipe ATM lol

[delcowizzid]

put the maf and IAT about 300mm or so away from the tb and after the BOV or when you shut the TB air tries to flow back out the maf and gets read twice.where did you have the maf before turbo i spose ,it doesnt really work there its to far away from the TB when it has to go through the cooler and pipework.you running L67 injectors if so it should run fine just on an l67 tune with the maf moved

[SirNemesis]

Compressed air is hot, so you want the IAT to see exactly what the engine sees and then tune it accordingly.

[ToMMMaY]

Awesome stuff boys I'll let youse know how I go tomorrow <3 thx heaps

[delcowizzid]

you getting it dyno tuned

[ToMMMaY]

Yer that was my plan waiting for my gbox manulizer and shiftkit wack that in should be popping mad chirpies hahaha

[delcowizzid]

hehe gearbox manualizer plug will give you full line pressure all the time she gonna change hard hope you have some good parts in the box

[ToMMMaY]

Yer done some reading on
It some people say they have had bad then
Some people have used it for ages giving it assholes in
Burnout cars lol and it's been good box is standard other then the transgo kit going in a corvetto servo