[72moneypit]

I use NGK V-power plugs now. What alternative choices are out there? I know I need 14mm gasketed 3/4 reach. Do I have to use 5/8 peanut or can I use 13/16 or 3/4? I would like to try one range hotter plug than the #7 offered by NGK, they load up in traffic and could be a little lighter colered after a long none stop run. any help would be appriciated. by the way the #7 NGK ran fine before I changed out to a longer duration cam.

 

[VinnyLSS572]

I have had good luck with A/C Delco R42XLS on my 572
Vinny

 

[72moneypit]

Thanks Vinny, are those the Rapid fire copper core?

 

[norvalwilhelm]

I run Accel plugs with good luck. My local speed shops seems to recommend Accel over all other brands of plugs.

 

[72moneypit]

Does anyone know if all the aluminum big block GMPP heads take 5/8, 13/16 and 3/4 socket plugs? What heat ranges have you had luck with? I am not sure how a #7 NGK compares to a 2,3,4 Delco or Accel for example. Any advice would be appriciated.

 

[engineguy]

Probably depends on which head you have. GMPP #12363425 raised port head uses 14mm plugs (3/4" reach) and Champion RN-4YC work well.

 

[69-CHVL]

I'm running the GMPP ZZ502 heads. I currently am running BKR6E which is a 5/8 hex. I tried a 13/16 hex and it wasn't going to happen - just to tight to get that socket in there. Oddly enough, the ZZ502 recommended plug is R43xls which shows its a 13/16 hex?