NGK for LT4?
 

Anyone use NGK plugs in their LT4? I've always used them in my bikes and AC plugs in my cars. I'm getting an intermittent misfire and figure it may be time to change the plugs. What do you think about the NGK split tip plugs? How much are they compared to regular plugs? Thanks!

Re: NGK for LT4? (Mr Dave)
 

Dave,
I always used the AC platinums that our cars came with, until I got into the motor last winter.
When I installed the More Perf top end kit, I started out with NGK 6 (stock # 4177), which is a copper plug and a bit colder than the OEM. To be truthful, the NGK 6s seemed too cold, especially in the back of the motor (#7 & 8 cylinders). The car went 12.2 @ 116 mph with those, but it seemed that the first run or two was down a bit.
I have since gone to the NGK 55 (stock #3951), a copper plug at the OEM heat range. They seem better, and I would recommend that you try them, if you want a copper NGK plug.
If you want a platiinum NGK at the OEM heat range, NGK recommends the TR55VX. It is either platiunum or iridium. Check out their web site at http://www.ngksparkplugs.com/
Paul

Re: NGK for LT4? (GS #883)
 

I use NGK TR55 platinum in mine. My factory plugs with 28,000 on them had 5 of the 8 platinum pucks missing. I would never use the factory plugs again in this car! Before I changed the plugs I also had a slight miss.

Re: NGK for LT4? (Mr Dave)
 

I use NGK TR55's in my LT1. They are fine plugs and not very expensive, $1.50-$2 a plug, far cheaper than any of the gimmicks.

Thanks Guys!
 

Thanks Guys! I think I will try the TR55VX