i was wondering if i change my plugs to 1 step colder am i gonna need a quick retune, or should i be fine....my setup is 20g9-5, 280's, 680's, hks dli, tbe....

 

if your not useing meth or somthing liek that and are on pump gas only there is no reson to go to a colder plug.

i beleave you would make more power on bpr7es then you will on bpr8es at this point in time

 

You wont need a new tune when going to colder plugs. If your not having spark blowout issues or other plug related problems then you should be fine with what you have.

 

On the stock turbo and the green I never lost power by going to a colder plug. If it's not misfiring I can't think of any reason why it would. If you are staying with 7s you can still make the switch to non-projected for some added insurance. FWIW, I daily drive BR8s.

 

I switched out the stock iridiums, and im using the copper NGK BR8's and i get backfires on decelleration....not sure if they need to be gapped more or less.

 

On deceleration the ECU cuts fuel, something was changed in that area, or the TPS is not working properly.

 

didnt know ngk had copper replacement plugs out for the evo 9. have a link?

 

I run the 8's daily driven with no issues as well.

 

get some denso iw-24's & never look back.

btw, dont change the gap on the "iw" denso plugs.