just finish installing the motor in the car. went to start motor only way it would run is if you held the throttle wide open at first, then it would spit and sputter sometimes backfire. went thru and check everything over again i know it is in time with the opti. after letting it set for a couple minutes tried it again still the same but i got a little better. let it set again after checking the oil &water started up at wide open throttle and it cleared up some more this time let it run for about 2-3 min. to break in the cam it still didnt sound right but i let it idle for a little bit to top off the water. went around to the inside to check oil pressure and rev. it up a little it started missing. so i shut it off and went around to the front and #5 and # 6 plug wire were burning i mean on fire. put the fire out and closed the hood ? this is on a 93 lt1 with a cc 304 30 over bore motor and a madz28 tune. everything is new in it except the opti, had it apart to replaced the cap and rotor and looked at the round metal disc in it and it was a little bent up on one side, recond this could be the cause of the problems i am having?

 

The bent disc certainly dosn't sound good so that could be a part of the problem. But it sounds like your 5 and 6 plug wires were touching your headers and burned up, possibly arcing also and helped contribute to the rough idle. I've done that once or twice before. Obviously, replace the wires that burned. Then check the plugs out and maybe replace the opti if the plug wires don't fix anything.

 

i am pretty sure the plug wires were not touching the headers,i had them tied away from them. they burnt about 8-10 inchs down the length of them. first time ever seeing that. i have had plug wire boots touching the headers on our round track car before and after a heat race finding them, but they never burnt like that. this is on a friends car.

 

Hrm. The only other explanations i can think of is too much current was going through it, but i don't know how that would happen. Or somehow there was an amazing amount of resistance in those two wires causing them to heat up, melt and cause a fire.

 

yea thats got me. i know the header tubes were not red hot either. so i dont know, will try swapping the opti out with mine,i know it works. then will see.

 

anybody else?

 

Yeah, the optical sensor being bent will cause serious issues. Should have just bought an entire opti.

 

Just for a possible other option, you did not list if you put in different rockers. Mine would do the same thing if the rockers were to tight. Just a quick easy free fix, but if you do not have roller rockers I woulkd definately check into that opti.

 

just installed a brand new opti with cap and rotor. left the stock rockers arms on. it will try to start but dies quickly,thought it might fuel issue but sprayed a little fuel through the t.b. would not even hit then. i thought i was thourgh on the timing part of the rebuild. but it sound like it is lazy trying to start&run. guess i will pull the front cover back off and recheck everything again. unless anybody else has opinion on what it might be. have rebuilt two of these before with no problem starting after rebuild????????

 

finaly found the problem. it was me about 1/4 inch off the alignment for the opti,from the rotor button pointing at #1. boy was i glad to hear it start and run for the first time.