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Hey everyone. Got a bit of a problem hope you guys have some insight and help me with an idea.

The car is a Cefiro. RB25 with a bunch or interesting things done to it. RB26 crank, rods 87.5 bore, 10:1 comp, welsh removed on factory RB25 head with some sort of 25 cam shaft combo. I know they are HKS but not sure of spec. Have an adj ex cam gear and the VVT disabled. GReddy TDO6 25g 16cm 1bar on C16 gas.

Now problem is just a sound for now. Car is set up for drifting. We know the turbo is gay for this so dont make fun of our lag monster. After we do 2-3 hard laps I get a tick tick come from the top end. Its hard to pin point the location but sounds like a lifter or even some sort of exhaust leak but its not. After I cool the oil down to 60deg and shut off the car and turn back on a couple times the tick goes away and we go for another lap. The tick didnt bother me too much as we are going to be changing our set up SOON but since money got low and I need to use this engine for 2 more rounds of our series and I just want to see if any of you guys have any quick fix ideas to this problem. or just a general idea if you've run into something like this before.

Now the guys that built the engine a year ago are not reliable and I dont even trust anything they say or did to the engine so I can not tell you if there was a oil restricter was installed. They did say the head was serviced but thats about all I can tell you. My oil/water temps are fine, tune is healthy.

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If this is occurring during/after a session, have you considered the type/grade of oil you're running? I wonder if once the oil is hot that it is simply a bit too thin to maintain adequate pressure in the hydraulic lifters and they are bleeding out a bit?

Maybe something like a 10W60 is what you need.

If this is occurring during/after a session, have you considered the type/grade of oil you're running? I wonder if once the oil is hot that it is simply a bit too thin to maintain adequate pressure in the hydraulic lifters and they are bleeding out a bit?

Maybe something like a 10W60 is what you need.

Ya, thats an idea I've thought of. We were using a 30 weight and I went to a 40 for last race and it did'nt make the problem any better. I'll give the 60 weight a go next practice to see what goes on.

I've also been getting a bit of oil in the catch can. It varies, sometimes I will get nothing and then sometimes I will get 1-2 ounces with a few hard laps. Thats why I was opting for the heavier oil to see if this changes as leak and compression are good. So it does seem like the oil is a bit thin and too much up top in the head. This engine also has RB26 valve covers on the 25 head. The baffles in the rear look good so it does'nt seem to be part of any problems but maybe you guys might have something else to say about that.

Any more ideas very welcome :O

Edited by RB30 Ceffy

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