I read the spark plug faq and used the search button but I was unable to find any answers. I have a 93 mustang with edelbrock heads( performers with 1.90 valves) and a ptk kit. I was wondering if ngk tr-6 plugs will work in edelbrock heads and if they would be the correct heat range. i was under the impression that they are 2 heat ranges colder than stock. I will only be running 8-10 lbs. of boost. Thanks for the help.

 

If going with NGK, I suggest a #8 heat range to start with. You can go colder with a #9 if needed.

 

So is the tr-6 the stock heat range for a 5.0? Also would the #6,8,9 ect. be the correct reach for edelbrock heads? I am not dead set on ngk, I just happen to have a set laying around. If there is a better plug option I am all for it.

 

I believe the #6 NGK heat range is the stock heat range. #8 or #9 is on the colder side.

Go to NGK's site and find a plug number that matches your head requirements. Or just do a plug number swap and then change the heat range number to #8.
(don't know what part number your head requires)