Blackbirdws6

iTrader: (7)

I'm picking up my new engine on Saturday and already purchased a set of NGK BR7EF plugs. Most seem happy with their performance but what gap would you recommend I run? I'm pushing max ~19-20psi from a F1A and was thinking 0.028-0.030 would be ideal. Not that it should matter but this is a LT1 car.

Shownomercy

iTrader: (1)

I think stock gap is around ~.055 good sir, the "OPTI" won't like such a tight gap and may blow the coil.

x275radial

iTrader: (1)

I was gonna gap mine around .045 and give it a shot.

Tally TransAm

iTrader: (17)

I gap my BR7EF's around .030-.032. never had an issue

silver_82

Use as much as you can get away with. Ive had to bring the gap to .016 on mine when i was at 26psi. More than that and the coils wouldnt fire and the engine would break up badly. I was at .24 at 18psi.

Whats the ingnition system consist of?

JoeMama's GTO

iTrader: (3)

I run the stock .024 on mine, 680 to the wheels.

Blackbirdws6

iTrader: (7)

I was running AC Delco R42-LTS when I was pullied for 15-19 lbs (710rwhp) of boost and didn't appear to have any issues. Gap was 0.035 but on recent inspection, they appeared to be a little hot for the combo. I am running the EFI LS1 PCM conversion for the LT1 cars so I no longer have an opti. The conversion uses 8 LS truck coils and the LS1 PCM. It's been a great setup so far.

Sounds like somewhere around 0.030 should be a good starting point.

coolmanvette75

iTrader: (2)

I have the same plugs gapped at .025 going into mine Brian...

trans2000am

iTrader: (49)

for that much boost i would think you would blow out the spark at high rpm with gapping them at .30

Johnv

Depending on how much of a pain they are to change , I would start at 25 thou and go down from there if you experience breaking up.

danieloneil01

quarter inch?

robsquikz28

iTrader: (246)

my old lt1 was a br8 plug at .032 19lbs boost