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I know a lot of guys don't like using the original setup of using intake vacuum to act as a pump to draw out the crankcase pressure but for me, it is the best way to set it up.

The claim is that it somehow reduces the power of the engine, I would need to see proof to believe that but I'm sure there is a bit of merit in it.

When I got my car, the catch can was vented to atmosphere via a filter on one of the inlets/outlets and the intake pipe inlet was blocked off. My car would get blowby when it was cold and would blow smoke out of the exhaust about 5 minutes after starting the car. As soon as I re-plumbed it back to factory, no more blowby (and associated horrible fumes into the cabin) and no more blowing smoke.

With the engine I'm building now (30/26), I've had two fittings welded into the sump, one to equalise to the back of the head (aka head drain) and the second one will go to the catch can. My can will need 2 inlets (rockers and sump) and one outlet to go to the inlet pipe. I'm assuming (and hoping of course!) that this should be perfect.

Anyone have any feedback on this??

Well, nitto oil pump, block one and 1.5mm on my rb25det didn't last 30mins on dyno, seized the cams

WHAT????????

really? break cams or just damage journals? thats crazy, was the restrictor smashed in when it got hammered down?

Did the cams caps get tensioned? And what tension was it?

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WHAT????????

really? break cams or just damage journals? thats crazy, was the restrictor smashed in when it got hammered down?

Did the cams caps get tensioned? And what tension was it?

Yep, got the call from the tuner, he was putting some ks on the motor running it in, revs started to drop and car shut off, try to crank it over but it turned as if it had something seized in it, try to turn it over by hand and couldn't, thibk the tuner is going with seized cams coz of that tapping noise it had and was thought to be lifters

Won't find out the damage till I get the car back and start pulling things apart, 30mins of its life and its already dead, over it

Sorry I wrote it wrong. It's to relieve pressure from the sump. So basically I have 2 lines from the cam covers and 2 lines from the sump that run to a catch can that vents to atmosphere. So I should look at running a second can that is an oil air seperator then plumb that back into the turbo side?

Well, nitto oil pump, block one and 1.5mm on my rb25det didn't last 30mins on dyno, seized the cams

Wow...something not right there. I've got a standard pump with one blocked and 1.5mm and its going great. Hope it isn't too bad!!

I know a lot of guys don't like using the original setup of using intake vacuum to act as a pump to draw out the crankcase pressure but for me, it is the best way to set it up.

The claim is that it somehow reduces the power of the engine, I would need to see proof to believe that but I'm sure there is a bit of merit in it.

When I got my car, the catch can was vented to atmosphere via a filter on one of the inlets/outlets and the intake pipe inlet was blocked off. My car would get blowby when it was cold and would blow smoke out of the exhaust about 5 minutes after starting the car. As soon as I re-plumbed it back to factory, no more blowby (and associated horrible fumes into the cabin) and no more blowing smoke.

With the engine I'm building now (30/26), I've had two fittings welded into the sump, one to equalise to the back of the head (aka head drain) and the second one will go to the catch can. My can will need 2 inlets (rockers and sump) and one outlet to go to the inlet pipe. I'm assuming (and hoping of course!) that this should be perfect.

Anyone have any feedback on this??

The reason people go away from factory crankcase ventilation systems is that it does cost power...but for a non-obvious reason. oil mist, when ingested by the engine along with the fuel-air charge, causes an effective octane rating decrease (ie, it makes the engine more likely to ping). When people startto push lots of boost into engines they tend to get more blowby and more oil mist. That is a no-no when you're pushing the engine closer to the edge of pinging anyway, let alone having more oil mist getting burnt as well.

Sorry I wrote it wrong. It's to relieve pressure from the sump. So basically I have 2 lines from the cam covers and 2 lines from the sump that run to a catch can that vents to atmosphere. So I should look at running a second can that is an oil air seperator then plumb that back into the turbo side?

That's what I am going to do. However there is so little coming out of the cam covers now that I will plumb them direct to the second catch can and leave the first one just for the two lines from the sump (and breather to the second catch can).

sucks to hear man. So for 30 mins of running (idling?) it just conks out all of a sudden? Tuner was obviously monitoring temps and pressure?

It was sent to tuner for run in tune, he started off with it idling checking the timing adjusting the cas, then I left, then got informed of what happen, he was making a new map for this tune so was getting everything ready he said the highest rpm they got to was 2500rpm it shut off on idle they said, it had a tapping noise in top end from first ever start up was thought to be lifters havnt self bleed yet turns out it was more then that to have the motor lock up

From what they telling me it just started to die down in rpms, try to restart it and

Nothing wouldn't, thought it was flat battery put jumper pack on still wouldn't move, try to spin the motor over by hand and it wouldn't move

Yeah tuner said oil pressure was fine, and has said with the amount of noise the head had and we all thinking it was lifters he said its more then likely lack of oil to the head resulting in this

Edited by mickr33couple

Sounds like bottom end. The timing belt would probably slip teeth on the cam but still turn over if it was being cranked over with a jumper battery!

I could be wrong however. If the timing belt was super tight possibly not.

Who built the engine?

Sounds like bottom end. The timing belt would probably slip teeth on the cam but still turn over if it was being cranked over with a jumper battery!

I could be wrong however. If the timing belt was super tight possibly not.

Who built the engine?

Nah motor wouldn't turn over with jumper pack, and timing belt was tight could hear it when it was running, it had good oil pressure alround, I'm thinking block wasn't cleared out the best and there is a blockage to the oil feed to the head, with a block and 1.5m restritor should be able to see a fair bit of oil in the head still,

Won't name names of the engine builder yet till I work out what happen, have spoken to the engine builder he says if cams seized it will be from no oil which he didnt wanna restritor in the first place also said if bottom

End is seized to bring him back the engine to pull down and see what went wrong

It wouldn't take a very large particle to block a 1.5mm hole. Sorry to hear anyway Michael.

I am heading down a similar path with a blown Evo motor (going 2.4L stroker, self built), hopefully it's oil feeds are clear and the bearings aren't too munched...

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