Hi guys,


I am wondering what i should gap my plugs to i bought. I bought some AC Delco Rapidfires and i was wondering if i can gap them bigger than normal? I have a Hypertech Coil and a Hypertech Cap and rotar. Would this allow me to gap the plugs bigger and if so, what would be a safe gap? Thanks

Chris

 

I believe AC Rapidfires are 'pre-gapped' and not supposed to be re-gapped although I usually don't listen

 

I bought a set of ac's sunday (r44). I gapped them at .50 and all seems well. I might try to pull them and try it at .45 and see if I can tell any difference. Just depends on how board I get.

 

I remember the '74- up HEI systems calling for a .060 gap way back years ago.But that was on large displacement Pontiac applications. Didn't own Chevys at the time. Then as the 80's rolled around they seemed to fall to .044 - .045. Maybe cubes has something to do with it?? I don't see why the components couldn't still handle the .060. Also I've changed plugs before and the gap had worn way above .044 .....couldn't tell much difference when I went back with correctly gapped ones!

 

jfox55 have you always run the ac44 or are you trying something different? I looked at your sig and noticed it's only a 9:1 motor, I just went through a big to-so at the track and guys were giving me **** cause I stepped down to the colder plug. Mine is a 9:4 and I've been running ac45, stepped down 2 heat ranges to the 43 and had mixed results. Had to jet up 4 numbers to get the color back and the car ran very inconsistent considering. Next morning switched her back to the 45's and we'll see what happens Sat. I've got the Hypertech cap, rotor, and the Moroso high output module and switched my gapping to .50. Alot of guys said the norm is .55 with the HEI ignitions, my truck recommends .54 (Ford though) friends Chevy supposedly .55

 

You know what man, I switched from the accel's. But come to think of it I think it use to have the 45's in it. That's what I told them to give me at the parts store, but I just looked and they are 44's. Guess I will probably be making another trip to the parts store. D*mmit.

 

Rapidfires are pre-gapped AND are already gapped more than a standard plug would be. My car has stock ignition and is supposed to have a .035" plug gap, but with Rapidfires the gap is SUPPOSED to be .045". I spoke with a tech at Delco and he said they are made to be gapped larger and shouldn't be reduced.