I've had my '71 142 for about a year now and it has been a blast and I've learned a ton. One thing that has always bugged me is that I have to be pretty careful driving it to avoid serious ping. For example, full throttle and third while accelerating briskly onto the highway would be some serious engine abuse. After making sure the timing was set correctly and the plugs were the right heat I shrugged my shoulders and said 'well if I could run better than 93 octane and perhaps some lead like the designers intended my problems would go away.'

Although I have a 32 year old engine of dubious maintenance and 10.5:1 compression I think it should run better than it does. Beyond, air filter, valve clearance, plug temp, vacuum leak checking and ignition timing, my next step is to check the fuel pressure regulator to be sure it's putting out the required psi and perhaps throw in another set of plugs (one step down in heat?) Are there any other suggestions? Could a disintegrating fiber gear cause this kind of noise under high load? When I set the valve clearance last week none of the lifters seemed too lazy.

Is there a consensus for making these high compression, low tech motors run on modern fuel or is the formula to start investing in 5 gallon cans of tolulene?

Thanks

Joel