Effects Of Cams...?

[Draconis]

Okay, I have a RB20DET. I put Tomei cams in there. 256/8.5mm.

So, I'm working on the engine since I have recently parted with the shop that did the work for me and went through the FSM and found that the shims are in the valve setup and they are in relation to the clearance and the camshafts. The FSM says there are 70 different types of shims ranging in size with a 0.05mm increments. They range from 2.5mm to 3.75mm... I believe... or something in that range.

Has anyone played with cams of this size and can give me some pointers with what else I may need to do with the head? My head is stock with these Tomei cams, which I was told were able to be swapped for the stock cams and will work just fine.

Thanks.

[Adriano]

Usually they drop in, and only need one or two shims to be changed

[heller44]

isn't lash adjustment on rb20's hydraulic? or have you had the valvetrain changed to solids?

Edited February 28, 2008 by heller44

[Draconis]

No. I do have the stock hydraulics. But what confused me is that the FSM shows shims... I thought hydraulics were to get rid of the issue with the shims. I dont know. I just saw this and was wondering if anyone else came across this issue.

[gtst25]

Nah rb20's have hydraulic lifters - same as the 25's - I put pon cams in mine and they just bolt in.

Cheers

[Draconis]

Well, here's the issue. I put them in and shortly after I heard 'lifter' noise. My oil pump is fine. I didnt know if it had to deal with shims. I know they are hydraulic, but the FSM states that there are shims in there. Makes no sense to me. I put the Poncams in and yes, they are bolt in. It would happen every so often then disappeared altogether. About a month later it happened about every day. Along with the 'lifter' noise, there was a loss of power. It would be a constant clicking noise but when I revved up the engine, the clicking noise would increase in speed also. I opened up the engine. The cams look good. No lifters are cracked. There is oil everywhere. LOL So it is apparent that oil is getting to where it needs to go. And I dont have a magnet so there is no way I can take the lifters off due to the vacuum created by the oil.

[Sydneykid]

RB20 = old engine, manye K's perhaps? Lifters do wear out. You have incereased the lift so the old lifters are now working in range that they haven't ever previously worked in. This causes leak down of the oil pressure from the lifter. It's not unusual to have lifter noise when you put new cams in, it happens quite often. The permanent solution = new lifters. You might try some heavier grade engine oil, if you are using 5W30, try some 10W60. That sometimes works.

Cheers

Gary