hi guys its been awhile...heres my dilema..87 gn...had the wirng cleaned up on the car..got it back to factory..(ie removed alarm stereo stuff etc) new ac delco coil/module, new chip, new air meter, new trans, exhaust etc..this is the problem after driving the car for about an hour or more..it starts stumbling/cutting out under load..car runs great when cold and up to temp driving for about an hour..it runs good beyond that in the cooler weather...yesterday it was 85 or so..drove 30 mins on the highway..then shut off for 25..then 15 then off..then 20 mins of traffic..then another 20 on the highway then it staarted its "thing"..once up to speed it seemed ok just light to medium accelaration..after another 15 min.s to get home (highway)..i was able to get it to miss when just lightly reving to 3k..let it kool for s..then another 40 min higway and traffic fine..sat for 30 then 20 min. of traffic..then it started again!!..got worse the closer to home....so just wondering if anyon has been here before?..just looking for ideas..i def. feel its heat related?..ideas..thanks guys!