I recently bought a 93Z28 with a 383 stroker LT1. The car will not idle but can be kept running by keeping the RPM's at least about 1500. It is not throwing any codes. It is definately running rich (black smoke and fuel smell). We tested the injectors using an injector pulser and all seem to be fine. The optispark appeared to be the culprit so I changed it but no luck. It has Taylor 8mm wires and an Accell 300+. I changed the plugs with Bosch Platinum's gapped at .050 because that is what was in the car before and seemed to have a gap of .050. When the car is being cranked, from underneath, it is obvious that there is spark arcing from the boots of the wires at the plugs. I replaced all the wires (not 8mm) on the driver's side of the motor and still have spark jumping??? On the passenger side of the motor there is also some arcing sparks. Is it the brand new Bosch Platinums or the gap??? It doesn't seem to be the wires since I installed brand new ones and the problem still exist. Any suggestions would be greatly appreciated. I have had 2 other LT1 vehicles before this one and have been lurking on the site for years. I have always found what I needed by searching but this one really has me stumped. Please let me know if you need more info. Thanks.

 

my 95 still has arcing from the plug hex to the block. Profesionals have told me it was just the halo effect, but I am not convinced. It seems to have a bit of a miss at idle, but after idle it completely disappears. Maybe the same prob or not. I have msd coil, msd 8.5 wires, rapid fire plugs, brand new opti... I am stumped too.