I am currently running ZFR7F-11 plugs gapped to .025. This is on a boosted D16 making about 270WHP. I'm going to get tuned on 20+PSI soon, to make around 350WHP. Since they discontinued ZFR7F, I was told to go to BKR7E. But now that I'm going to be making more power, what plugs should I use? Since the 7 Step is the coldest step for the BKR series. I have seen racing plugs that have colder ranges but they are typically non-resistor. Is it ok to run non-resistor plugs? What are the alternatives?

 

For that range from what I know BKR7E's are a good choice. I order mine from summitracing, since they stock them, shipping is quick as hell, and its only ike 5 bucks for shipping.

They are resistor type..


http://www.summitracing.com/parts/NGK-4644/

 

So I should be good with the BKR7E's on 350WHP?

 

that depends. you should do plug read if you need colder plugs

 

what does that mean exactly?

 

read on plug reading. or just ask ur tuner for it.
he'll know if u need colder plugs

 

i'd run an 8 heat range, 7's will probably be ok but if you are too hot you'll melt a piston, if you are too cold you'll just foul the plug.

 

yea I was thinking about running 8 heat range, but on what plugs? Regular plugs dont go to heat range 8.

 

you can get R5671A-8's (non resistor plug) or you could go BKR8EIX iridiums.

i wouldnt use the projected spark plug you are using now. asking for hot spots....

i think BKR7E's would work great for your goals.

 

yea I am changing from the ZFR's. And i've heard that the iridiums do not work well in boosted setups because the finewire electrode gets burned up/off.

And can I run non resistor plugs in a street car?