Dear Jack.....I just bought a 74 Pantera # 6434, it has the XE1 block, fuel injection, Haltech, Weber throttle bodies, non-roller solid lifter cam, And a full Mind Train super loud exhaust system. The valve train sports: 4V heads, Crower Enduro stainless roller rockers at 1.73 ratio with 7/16ths screw in studs, 3/8 push rods with guide plates, the valves are single groove retainer type with double springs with the harmonic third spring and I see a bit of purple color on the bottom of the springs. I have measured the total Exhaust valve lift to be .574 and total Intake lift at .560. I measured this by setting the lash to zero and then taking the measures of the valves closed and then at total open from the top of the valve spring retainers/cups (bumping the motor over to do so). I do not know who makes the cam or it's part#. I plan on taking the front end apart to be checked this winter. The previous owner said he had the same problem, but that he set the lash for intakes and exhaust to .028 When I opened the valve covers and checked the lash on a cold motor I found the lash to be between .022 to .026, with a trend of the intakes at .024 and the exhaust at .026 And yes, driving it home 1400 miles after the purchase sounded like we were being chased by noisy beetles from the valve and injector clatter and then followed by the thunder of the Gods from the exhaust pipes. The local Go fast shop tells me to set both intakes and exhausts to the same lash at the .020 to .022 range. The motor runs very lopy up to about 3500 rpm and then it cleans up and screams smoothly past 6500 and then I back off before it hits the MSD rev limiter. I believe this motor has less than 20,000 miles on it. So my question is.....in your experience, what do you think is a safe valve lash setting for this motor. Thanks in advance................Doug.H
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