JimS

Having fouled plug problems and NGK advised me to run TR4's set at about .40 even with FI.

Any thoughts?

Yelo

.040".....NOT .40"

I'd be leary of running a gap above .035" with FI

parish8

iTrader: (6)

dont listen to whoever told you that.

stock heat range is tr5's. 4's are hoter than stock. everyone uses tr6's with good luck.

Mort

I would say to stay with the tried and true TR6. The TR4s are hotter than stock plugs and may not foul out but it would be better to find out why you are running rich and fix that problem rather than to try and mask it over with hotter plugs that may detonate when you least expect it. Have you had your tune adjusted to work with your meth kit? If not you are likely running really rich at WOT. Get your wideband fixed and correct your tune or O2 sensors and make sure everthing is running properly. I have a LM-1 and the Alky meth kit and I am having a really hard time to keep from running really rich at WOT using 100% meth. Get your wideband grounded properly or whatever the problem is fixed and see exactly what is going on with your tune. To me TR4s just smell like disaster waiting to happen. I am no expert but I think you are headed in the wrong direction.

JimS

You guys have far more experience along these lines than the guy who said I needed a hotter plug and Mort hit the nail on the head with his suggestion that I get everything else fixed instead of just masking the problem with a hotter plug. I just gotta find somebody who knows how to tune these trucks and work on the stuff that I don't know how to fix. Everybody I know still has carb/dist engines and doesn't have to worry about wb guages, o2 sensors and the like. I wouldn't mind joining them again either... Put a 572 in this puppy and go.

Thanks for your help guys. I'd have gone with the TR4's and maybe screwed something up royally if it hadn't been for asking the experts on performancetrucks.net