Hi, I have 2004 silverado 1500 with a 4.8, intercooled kb kit, and s475 which is almost ready to go to the dyno to get tuned. I have br7ef's in it which I gapped about .032. After reading a bit more, I almost think I should take them out and narrow up the gap a bit. Would just like some opinions. Max boost will be about 15 lbs.

Thanks

 

You may want to close them up to .030 or so. You dont want to narrow the gap anymore then you have too so maybe start there and see how it does. I have ran mine up to 14psi with .030 and not had issues.

 

Man that's gonna be a beast on your hands with your turbo selection. I ended up not liking my br7ef plug because of the way they acted at idle. And gas mileage went down. So I put tr6s back in it gapped at .028 and with the meth that controlled all my spark issues under boost

 

Ya, I'll just be using shitty 91 and meth. Just wanted the 7's to be on the safe side.

 

And as for turbo selection, I don't like the thought of backpressure robbing power. You don't see too many T6 4.8's running around, lol. Thanks for the replies!

 

Holy hell. T6? What turbine and housing you got on there?
Thread hack... Sorry lol

 

83mm 1.10 A/R

 

br7ef's at .026 running 16psi.