I currently have NGK TR5's at .38 Gap. This was done at the advise of a local chevrolet dealership. Im thinking the car could be made to run a little better with a plug and or a gap change. Whats the absolute best plug and gap to run on a stock ls1. AcDelcos or TR55's? And at what gap?


Thanks.

 

Tr5 or TR55 are r same plug you need to take them out and gap them to .55 and you should be running much better.

 

Not trying to thread hijack but I always wondered what gaping the spark plugs did? I run NGK's all the time but I just take them out of the box and put them in with no gap change. Your saying changing the gap will make it run better and I've heard that from others on here too but never looked into it and was just wondering if I should ...

 

Agreed, if you're not spraying any nitrous and don't have higher than stock compression, change them out for a TR55 and gap them .050-.055"!

 

sorry to but What kind of gap should you run if you have a higher compression motor.. say 11.3:1

 

Ok, now that weve established that, Ive been told it will make it run better but what in effect does gapping them do to the motor. Sorry if thats a noobish question but ive always asked what and never asked why.

 

 

I've got TR6s in my car with the same CR, I gapped them around .038

 

x3???