Colder plug help!
 

Hey all,

I was just given a set of Denso Iridium IT20 plugs. They are -1 heat range from stock plugs. Will they hurt the performance or damage the engine in any way now that I am not running a power adder :confused: Or should I just save them till later and keep running the stock plugs.

Thanks

One heat range colder is absolutly fine; even recogmended by a lot of tuners.

I 2nd
running that plug is just fine