I just bought an '86 Camaro, and I replaced the plugs in them. Only thing is I need to know the gap on the plugs. It's not the stock engine though, it's an aftermarket 350 crate engine. Does anyone know about what I should set the gap to? Thanks.

 

Give us the basic specs of the motor and ignition system, and we'll give you an idea of where to gap the plugs. If its stock ignition and a relatively mild motor, .035 or .040 is prolly your best bet.

- Justin

 

Okay-

350 short block with 2.02 heads
High lift cam- not positive on the powerrange exactly
Edelbrock intake and Holley 670cfm Street Avenger carb
Putting out an estimated 350hp 350 lb. ft. of torque at the crank
Edelbrock headers

Not positive on the ignition system, the top of the distributor says "Carburetor shop" on it. That's it.
I'm using Moroso Blue Max spiral core wires.

Do you need anything else?

 

Well, since you don't know much about the ignition I would stick with .040" - a small gap will cost you a touch of power, but it's better to be a little too small than a little too big.

I have a largecap HEI with a recurve kit, accel coil and 8mm accel wires, and I'm running a .045" on the car in my sig. Haven't really tested it yet to see how well it's working out since the car isn't quite road-worthy yet.

- Justin

 

Okay, thank you very much. Will the motor give any signs if I have the gap to large?

 

Hi, I'm bringing this thread back because I bought new plugs. I bought Accel 576S plugs and new BlueMax spiral core wires. Do you guys think my gap should be about .040?

 

I just bought a crate 350 and got the new Diamond Fire E3 spark plugs. They dont need to be gapped. They sell them at summitracing.com. They are similar to Splitfire but go all the way around.

 

well with a high powered hei .050 isnt out of the ?,bigger the better,if its too big your going to notice a misfire and possibly a back fire situation.too small harder to tell.it will run but power will be down..040 -.050 with hei should be ok.try try try

 

Allright. I think I'll run .042 or .043 gap. Most likely I'll step up to .043. Thanks.

 

Spark gap is something to play with like timing,although more of a pain because of the R&R involved.According to Jacob's Electronics ignition book you start at what the factory baseline(which is a compromise at best)and increase by .005 till you feel the motor flatten out.Off the bat if you have a hotter coil,better wires,top of the line cap&rotor(which should always be used) you can open the gap .005 to .010.I'm running .050 in my Jimmy(she gets 21mpg on the hwy).