am I going to notice any difference in my engines performance using a colder plug when I'm just running on motor....question just popped in my head...

 

You'll be fine in the NA application. Being a copper conductor plug, they will require sooner interval changes. I have read a couple of publications where one step colder,TR-6 plugs were swapped into a NA motor and a few extra ponies resulted on the dyno.

 

I would doubt that you would gain hp going to a colder plug. I run NGK br7ef plugs in my car. Car seems to run exactly the same. Only problem you may run it to is if you start the car in 30deg or below weather. It make take 10-20sec for all of the plugs to warm up.

 

Put a cold enough plug in it and it will foul with fuel.

 

The heat range does not add or detract from an engine's hp. Unless like Injuneer says, it fouls.

 

inj and andy, with the amount of nitrous you 2 guys dump into your cars, which plugs would be the best (and how many miles or passes) to live in a 11.8-1 motor with a 300 shot?

 

I don't run my nitrous plugs on the street, unless I'm being lazy. They come out black, and I don't like it. Definitely, in the summer only. The cold winter starts would kill 'em.

I run TR6s with the 180 shot or so. I'm not sure on a 300 shot. I run an all stock Lt1 motor, so I have to be careful on shot size. You'll have to do a search.

 

Running too hot a plug can lead to detonation. You want to run the coldest plug that doesn't foul.

 

Ditto with Andy... I can't run my nitrous plugs on the street. They would be fouled after 10-15 minutes of low load driving. I run Champion S57YC with the 300-shot, get by with Autolite 103's with a 125-shot, and 103's or 104's on the street. I think that's what they are.... I haven't actually raced or driven the car in so long I forget whats in it

 

i have tr6's that im running gapped a .035 now and i spray maybe once or twice every 2 weeks about.lol

 

I run the Autolite AR racing plugs in mine 4 ranges colder then stock and run them on the street also. I like to keep them in there cause i'm boosted also and then spray it at the track. I haven't had a problem with fouling them. I'm sure you won't need to go 4 ranges down, but probably at least 2. The other guys are right though, go too cold and the'll foul.

Ken R.