How about retainer's hitting valve guides. If the guides haven't been shortened they will. Pain to check in the car.

 

Yes, what technique are you using to adjust the rockers? Make sure and wiggle all of them while the the engine is off.

Also, if the noise is more refined on one bank of the engine, that should mean it is not a valve interference problem (at least not valve to piston). If clearence was a problem, you would hear the clack on all cylinders (both banks).

 

the rockers are adjusted correctly. I have readjusted them probably 25 times or so on this car. i went back to stock lifters. i have done several lash adjustments on roller rocker motors and i have never had to do it more than twice. this cannot be the problem. i bring every cylinder to TDC and adjust both intake and exhaust valves. i turn the pushrod by hand until i start to feel tension, then i go another 1/2 turn on stock lifters for preload. i've tried going 1/4 turn, 1/2 turn, and i've tried 2 other methods of lash adjustment and nothing has really gotten me any farther. the rockers are not loose or near loose enough to make chatter like loose rockers do. it's really hard to tell whether the noise is from one side or both. if you stand on the driver's side, it sounds like the passenger side. if you stand in the front, it sounds like both, and if you stand on the passenger side, it sounds like the passenger side. i have no idea. i'll have to check retainers hitting valve guides and rockers hitting retainers.

 

Call Bret and find out what's going on,he made the cam design.

 

I'm not trying to sound like a broken record but are you absolutely POSITIVE the cylinder is at TDC when adjusting? How are you checking this?

 

I've been emailing bret and his ideas havent gotten me anywhere either. as far as TDC, I check it by puling the plug and watching piston travel. However, it should not have to be excactly at TDC....as long as the lifter is on the base of the cam lobe. my cam has a large overlap as well so that helps.

 

new valve guides were put in and the retainers appear to be at least 1/4" away from the valve guides. the rockers seem to be clearing the retainers as well. I have the comp beehive springs. when set to height, the bottom 2 coils touch each other on every spring... when fully open, a 3rd coil comes down to touch the bottom two. the rest of the coils have good clearance and comp's beehives are supposed to handle more than .600 lift

 

anybody?

 

Adjust the rockers while the engine is running. This is the only surefire way. If you do each at TDC with the engine off, the valvetrain my not show the same slack it would at 1000rpm.