Spark plugs for single turbo FD

[Dizz]

Sorry if similar questions have been asked a thousand times but haven\'t been able to find a proper answer...
 
I have an FD running a T78 single turbo, just had the car mapped in WGT and have it back now but he put HKS plugs in with a heat range off 11 and as you can imagine they dont agree with the car when sitting in traffic etc. I\'ve heard about putting different heat ranges in leading & trailing but usually people seem to put 7s & 9s or 9s & 10s in. I\'m just wondering is it safe for me to use two of the 11s he put in & two of the 9s that he took out? It\'s just literally to stop it from "flooding" while in traffic.
 
Thanks for any help you can give

[kompactor]

Get an ignition amp. I run 10\'s all around, iridiums. And your tune will play a big role too. If your idling and cruising around with 12.1 afr\'s it\'s going to foul plugs a lot faster. Shoot for 13:1 idle and 14.7:1 low speed cruise. 16:1 highway cruise.

[yehreally]

http://www.mazdarotaryclub.com/forums/showthread.php?t=66333