This is my first LS and Procharger build and i need to know which spark plug to put in it to start with. It's a 9.5 to 1 402ci with stock 243 heads. It's got a F1A that is suppose to make somewhere around 14-16psi, running 93 octane with a AIS w/meth dual nozzle setup. Stock computer. If more info is needed, let me know. I picked the engine up today and they forgot to include the cam card in the info, all i know is they said it's right under .600 lift.

Thanks
Allen

 

NGK TR6 pn# 4177 gapped at .032. Bob

 

I am starting off with BR7EFS @ .027 on mine but most likely at our power levels I will go ahead and put 8's on it. They may foul out quicker, but its not like I wont be pulling plugs anyways. Plugs are cheap. motors are not.

 

Bob, I should of thought to ask you, as you always seem to have the answers i need. Thanks again #276. LOL How does the number system work for heat rating on them, smaller=?.

I8u4rd, I've been watching build as is somewhat similar as mine with alot more flare. Thanks for info.

 

I should have added they just stuck some Autolite AR 3932's in it to fill the holes for the haul home. Are they any count for this app?

 

3932 are comparable to NGK #10 plug, pretty cold for a street car, you could run them but would probably foul pretty quick...my .02

 

i used tr6's with no problems but recently going to try br7ef's

 

I would run the non projected tip plugs like a BR7EF.

 

Thanks again to everyone. May sound dumb, but what brand are the BR's you and others have mentioned?

 

I've never had problems with the TR6's, we've run a lot of cars with them including mine at 18 to 20 psi of boost. Below is a heat range listing. Bob


One step colder
Heat Range: 6
Gap: .035 - .038
Plug: NGK TR6 (stock number 4177); NGK TR6IX (stock number 3689); Autolite 103; Denso IT-20 (stock number 5326)

Two steps colder
Heat Range: 7
Gap: Consult
Plug: NGK BR7EF (stock number 3346); NGK TR7IX (stock number 3690); Autolite AR94; Denso IT22 (stock number 5327)

Two and a half steps colder
Heat Range: 8
Gap: Consult
Plug: NGK R5724-8 (stock number 7317); NGK TR8IX (part number 3691); Denso IT-24 (stock number 5328)

Three steps colder
Heat Range: 9
Gap: Consult
Plug: NGK R5724-9 (stock number 7891); Autolite AR93; Denso IT-27

Four steps colder
Heat Range: 10
Gap: Consult
Plug: NGK R5724-10 (stock number 7993); Autolite AR92

 

Awesome Bob. That really helped.

 

http://www.google.com/url?sa=t&rct=j...45960087,d.cGE

The TR6 plugs worked very well in my Camaro, shown here. Bob

 

NGK part #3346

 

Hey guys, i appreciate the help. I'm going to get a few sets that you all have mentioned(tr6, bre7's) to have when i take it to get it tuned just so i have options. This place and you guys are saviours.

 

I used BR7EF initially @15 psi with E85, but switched to TR6 for better idle quality... I think you can get away with a little hotter plug on E85