Spark plug NGK 6510
 

I got A little over 1,000 rwhp, and I just put this NGK 6510 spark plugs but they came at .040 is that good or should I close them down a bit. want my car to be running the way it should it won’t hurt it if I leave it how they came?

Depends on your boost bud. If over 15lbs of boost gap them at .028

What about for a ported stock blower at say 10–12 lbs of boost? .032ish?

I think JRE's been pushing around .040" for up to that boost.

I'm at about 700, and just put in 6509s, and with about 15-lbs, and .040", it sure is snappy.

It’s not going to make anymore power or run better at .040. I can’t run .040 on mine, I tried once, misfires once it gets close to 15psi. The coils/wires etc have enough voltage to jump the gap but blowout becomes an issue.

I'm only offering what's been posted here, as best as I can remember, and my experience. You're making a lot more power than I, so I don't know that I would be surprised by your experience. I'm certainly no expert :w00t:

A safe bet IMO would be .032 . It’s not worth risking spark blowout at .040, esp with no difference except a possible smoother idle.

I mean if the car is mostly stock esp with no cam running the highest gap is mainly better for idle. I’ve seen no performance improvements with a larger gap.

Basically you want to run the largest gap you can without spark blowout.

Stockish 9-11 psi is good for .040
Modded 12- 13 I like 0.32
14-17 I like 0.28

This is JMO but I think these gaps work best.

Im going completely stock with just the 2650 going on. Im going to use .035 to be right in the middle. Using the 90mm pulley, so I have no idea how much boost Im going to make. For the record, Magnuson said I could leave the stock LT4 plugs in there and run with that, they did not recommend a plug change but my tuner did.

.035 seems like a bit too much for a 2650, but give it a shot and see

For an otherwise stock car?

Odds are you'll be alright

Different platform, but I ran both 0.035 and 0.038 gap with TR7ix on my 5th gen ZL1 with about 16 psi. No issues with misfires/blowout.

You’ll make 16+ psi it at sea level if nothing else is done with the 90mm pulley.
I would gap Them 28-30.