Different spark plug heat range on e85?
 

Hi,

I hoping to be in the 500 to 600 WHP range in a 94 FD with large street port. I'm to the point where I can start tuning for power and am not sure what heat range to use with e85 since temps in the combustion area are going to be much lower.

I was going to use NGK R7420's 10 leading and 10.5 trailing but wanted to see what everyone else was using.

Thanks

I run 11's all the way around.

Good to know. If you don't have any issues with the plugs being to cold I should be fine. I know that piston motors have to go at least a full heat range warmer when running on e85.

Anyone else with high HP using e85 what to share their experiences with spark plug heat ranges?

That's one real benefit of e85...... I've torn down many high powered 13B-REWs making from 380 to 420 rwhp and the rotor housings always have extreme cracking on the inner spark plug boss usually at the leading plug. These guys were also always using standard 9s or the snowmobile plugs (b10egv, eix etc) and they're a horrible choice for boost levels above ~1 bar.

Ran all 9s previously. Probably wouldn't recommend it but, it worked I guess.....

R7420 11s are ideal.

Is there any drivability issues during warm up or normal cruzing conditions? If not looks like there is no reason not to run all 11's.

This is what I run.
http://www.shopgreddy.com/accessorie...lug-re-11.html
Hard to tell this time of year especially with E85.
Hard to start when it's cold and really doesn't run well until you are warmed completely up.

Thanks for the info.