Well, after another week of diagnosing the engine noise, we exhausted all avenues that we could pursue with the engine together. The noise still seems like it’s coming from the valve train, and the next thing to check is the lifters. We pulled them so that we could send them to Crane for evaluation. With the engine open, we had a chance to borescope the cam. We found one tiny pit in the #2 exhaust lobe, but the lifter roller had no damage, so there’s no way the noise is coming from that. We didn’t see any obvious damage to any of the lifters either, so we’re starting to worry that the noise is coming from somewhere other than the valve train.
With nothing more that we can do on the engine, I turned back to adjusting the pedal box. The pedal box normally mounts below the support plate, but that puts the pedals very low. I pulled the support plate and reinstalled it below the pedal box. That helped, but I really want to raise them further.
Since I made my own strut mount spacers, I dug through the spacers that came with the kit and found four that were about 5/8″ long. These are perfect; once we have the carpet installed, the brake and clutch pedals will be virtually exactly the same height off the floor as our 911.