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RB26 loud valvetrain - Vid inside.

Picked car up from tuner, now has BC springs and Kelford L182A cams. Valve train is noticeably noisier, can be heard in cabin. 

Tuner states he checked all clearances and "A few thou looser than before, but all within standard spec". He said he doesn't mind the clearances to be a little looser as a loose tappet is a happy tappet or something like that. 

I can have it reshimmed, but of course more time/money. 

Pros and cons of loose/tight clearances? 
 


 

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OK, so the noise is certainly from that extra clearance.  It is not better to set the clearances inside the "standard spec" when the cam manufacturer specifies that they should run at tighter clearance.  When the ramps start getting more aggressive the clearances need to tighten up to stop the lobes from slapping onto the lifter.

If you keep a really good oil in it and change it frequently it will probably be fine.....but I'm not enough of an expert to trust me.

Had this same noise from my neo when i fitted some 270, 9.2mm cams. Had all clearances set to what the cam specs said... After having them in and out numerous times, they sent me a new set with a less aggressive ramp and the noise went away.

Not saying that's your problem, just a similar situation 

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