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I had a quick search on here and i can't find it. What is the RB25DET valve clearance ment to be?

I found the RB26 one which is 0.42-0.48mm on the intake and 0.35-0.41 on the exhaust but obviously the RB25 will be different becuase it is hydraulic.

I just wanna check it with the HKS cams and see if this is the cause of all this f***ing around.

Thanks guys.

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I thought you place a fealer gauge underneath the lobe of the camshaft and then depending on the outcome of that you replace the thickness of the shims? Isn't that it or am i thinking of something completely different? :geek:

Edited by PM-R33

Ok i just had a better look at the service manual and it appears that the valve clearances are the same for the RB25 and RB26, ill be damned. I would have been 100% sure they would be different, can anyone confirm this?

I thought hydraulic lifters don't need shimming as that is the whole point of hydraulic lifters.

Hmm so hydraulic heads dont have any sort of shims or anything in them? Only solid lifters? I wonder why Advan would say to check the valve clearances then :P

cos they didn't get the whole story maybe, like bubba said, hydraulic lifters don't need checking they pump up and hold when you start up your car. They only need replacing when they are shagged. ie don't hold pressure

OR maybe you got 26 cams.. did you get springs aswell?

26 cams & springs with hydraulic lifters I think leaves a bigass gap.

OR 26 cams with your stock springs and lifters would probably also run like shit as I believe the ramp rates for solid and hydraulic are different...

Nah they are definetely RB25 HKS Cams 256/264 (Part #'s RN172 Inlet, RN175 Exhaust) but it is still standard springs. The springs is the only thing that is still a bit questionable, would it really cause the car to run that crap though?

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