Originally Posted by Unreal (Post 1585679051)

Aftermarket cam, stock rocker arms, last ~4k had the comp trunnion upgrade. In fact, the rockers are probably one of the few non-aftermarket things in the engine bay. Block, pistons, rods, crank, valve covers, alternator, headers, blower, etc is all aftermarket.

Coils, front cover, rocker bodies, and sensors are all OEM. Everything else has been changed.

Originally Posted by Hib Halverson (Post 1585676544)

About that video...

I got my sectioned LS7 head off the shelf and took some rough measurements (ie: eyeball and ruler) of the part I have that's a sectioned exhaust port, half a chamber cut right down the CL of the exhaust guide.

Eyeballing the position of the dial indicator as shown in the video, then measuring half the guide (about an inch) plus the apprioximate distance from the guide down to the head of the valve, as shown in the video–say 3.75-in.–then, using trig, working out the difference between the observed clearance (.020) and what it would be if the measurement was taken in the proper place–it looks like the difference is a factor of about 3.8. That's huge.

So, to put it another way–if, measured the way it was done in that video, you saw .020" clearance, the actual stem-to-guide would be about .0053, which is well outside the Service max. tolerance of .0037

Nevertheless, I think I'd be careful with any conclusions you make if you measure stem-to-guide the way the video does. For example, let's say you saw .010 on the indicator, measuring the way it was done in the video. You might think OMG! But...the actual stem-to-guide would be .0026, well inside the Service tolerance and just a tenth outside the Production tolerance of .001-.0024.

Originally Posted by Vette @ 71 (Post 1585690527)

Could you also determine what the correction factor would be for the wiggle test where the dial gage is about .5 inches above the guide and the valve is just off the seat. Would be great to put the wiggle results in perspective.