[silver68]

One more thing, I can explain why you must "degree" the cam. On both of my personal engine builds each cam was off 2 or more degrees. Never trust a timing chain set with multiple keyways. That is especially true of cloyes true rollers.

["Puddles the Pontiac"]

thanks for all your help and i do plan to check out the mentioned web sites.

as for tuning, the plugs look good on all three levels of the porcelain. as well, the electrode is showing that i do have the correct range plug. after rechecking, i had found some of the gaps to be off. all are reset to .045.

an issue i am having is that i am only getting about 10* of mechanical advance (there are no provisions for vacuum adv.) i am looking for a weight set to get me more, i do physically have more room for more advance (via the slots), but the weights are stopping early. i am looking around for stock weights now.

i know i cannot compete with a wide band. but my idle, off idle is great. not a stumble or pop to be found. the engine will "bark" with a quick stab at the pedal. not to mention the thing will start like a new, fuel injected car. i do have serious traction issues and this car is quick.

but the miss is still there. and it is a light miss (not a surge) which leads me to believe it is in the ignition. i can best feel it during "cruise" situations. i plan to change the coil and module. i can see nothing physically wrong inside the distributor.

fyi, i do have the new cam in (290b-6). the cams lobes all survived break in. at a 106 lsa there is no issue with a lack of dynamic compression (thanks screamingchief for the cam lesson last year). these are 93cc 6x-4 heads on a .030 over 455, zero deck. you are right to say i am guessing the static compression ratio when i guess 9.75 to 10-1. and i am going to use a friends inductive light when setting timing. i will get back to all with any new results. again thanks to all.

p.s. does it make anyone else nervous to see their oil pressure drop to 10lbs at idle? i have never gotten over that.

[MikeB'70Tempest]

5-7 cross fire maybe?? Are the wires running next to each other??

[silver68]

Try gapping the plugs at .035, I may be mistaken but I have heard wider plug gaps cause more problems than performance gains. Also use wires with a low ohm per foot rating. Parts store brand wires are notoriusly problematic and have very high resistance, even when new. Make sure you have 12 volts going to the hei, use a volt meter not a test light. The power wire to the coil was a resistor wire from the factory and does not supply 12 volts. Be sure your alternator is producing between 12 and 14 volts and that you have proper grounds fromthe engine to the frame to the battery.

["Puddles the Pontiac"]

well, here is an update.

i tested the pickup and ignition coil. all are good. replaced the module, no improvement. tested all my wires, they are about 5000ohm/ft. (stock wires). plugs themselves all look the same.

now my misfire has increased to a "popping" out the exhaust pipe. sometimes even a full backfire. and it seems as if i have a spark plug wire unplugged.

now i am going to recheck everything mechanical. i will do a compression check and check my cam lobes and springs.

i have NEVER had a miss this hard to find. this is INSANE.