Spark Plug for L35 heads 2 steps colder

[Mikeysy15]

Does anybody know what NGK spark plug can be used for L35 heads that are 2 steps colder then stock . I was using UR6 but I need colder plugs as these are getting hot under high boost . I purchased 6 brand new BR7EF but the thread is longer . Would that matter ?
Plugs are for E85 . Any help would be appreciated

 

[proptop]

Mike let me take take a
Look at the chamber on a L35 Head. I believe the tread length is .688 and the uon’t work however I will look for a good plug for you. Bob

 

[proptop]

Stupid phone autocorrects

 

[proptop]

NGK R5674-7/5034. I will send you a pic in a minute. Bob

 

[WyoSyclone]

I'm starting with Autolite AR24 plugs in my L35's..... not sure how they'd work with E85. Thread length on these is .400"