Trick Flow heads and E-85

Anyone running Trick Flow 240 or 270's and using E-85 for fuel. Looking for a spark plug recommendation. Thanks Birdtracker

I haven't bought and used a set of those heads yet on my bracket E85 S/P car yet but if they take a 3/4 inch reach plugs like SB and 426 hemi use try a Autolite #3933 or the next hotter 3934.
I have ran these plugs in both of my bracket motors with aluminum Eddy Victor M.W. on the old motor and with the Indy 440-1 at 15.0 to 1 compression on the new 400 block stroker motor
IHTHs

I'll be doing the E85 change soon. Running 440-1s on a 540 @ 13.5:1. I like NGKs, and it was suggested that I start with the -9 heat range plugs.

I use the NGK 7 non projected tip with the 240 heads on E85. 440 with 13.2 Ross dome pistons, stock stroke.

It's a Mark Sullens Dominator.

Mike

My first E85 motor (14.5 to 1 comp) did NOT like cold plugs, I was running the retracted gap Autolite race plugs, 3932 slow the car down compared to the 3933 and 3934, 3932 being colder
The new motor is close to 15.0 to 1 on all eight cylinders and I'm going to be doing more tuning and learning on it this year, if we ever get to race like normal

The NGK -9 plugs are very cold for normally aspirated engines. I suggest starting with -8 for 13.5 CR.
The -7 might even be fine for longer plug life.

We made the switch to E85 this season. I have 440-1 heads and run the -8 NGK. They seem to work good. I ran -9 plugs with Methanol and they worked ok. I read E85 likes a hotter plug.

Old thread revival....

Would the NGK R5671A-8 plug be a reasonable place to start with a 12.5-1 E85 RB?

No
I have ran my 800 HP bracket motor on E85 since 2013, it does not like cold plugs at all I would start with a retracted gap NGK-6 (sorry for not knowing that part # ) and then maybe try a -7 later to see what your motor likes.
I use Autolite race plugs, part # 3934 3/4 inch reach, 5/8 plug size with a retracted gap

Thanks cab, I'll start there then.

Cab is correct, 6 or 7 on the heat range, and also non extended tip for E-85. Birdtracker

My 408 (Eddy heads),13:1 compression uses NGK R5671A-7 plugs. Works great.

Have you tested a hotter plug in your motor on a back to back test with no other changes?
If not me thinks you should I'm pretty sure you will be surprised

also E-85 likes the blue HVC coil. I changed from a Blaster 2 to the HVC and the difference was tremendous.
Birdtracker
https://www.jegs.com/i/MSD/121/8253...08M7P7AIVxwiICR0QxgwZEAQYAyABEgIl5PD_BwE