I will b running na for awhile so i wana run hotter plug. The motor is 355 21* heads and 12.1 compression. What plugs do yall think i should run. Thanks

 

r5671a-7

 

i was thinking the same thing. running the 5671a-8 now. Im a noob on plugs. Do u think i would benefiet running the hotter plug

 

i have some -8s sitting in the garage, haven't thrown 'em in there yet to see how they do. The -7s seem to look ok in there right now. I'll be doing -9s when the nitrous starts flowin'

 

I'll be on a BR8EF on the big shot, probably a 7 to start out, but I'm on E85 and it likes a colder plug.

 

yall guys think a 6 will be to hot.

 

-6 will do ok, you'll have to run a projected tip to get it though, something like an autolite 3924 IIRC

 

How do you figure that?

 

I figure that by a lot of guys making 1,000+ HP with it saying so. I've used it and methanol in 2 strokes and we ALWAYS run a colder plug. Helps control heat concentration on the top of the piston for one thing.

 

Ok, but the fuel burns cooler than gasoline?

I have personally had success using plugs that would be too hot for gas. When I used colder plugs on E85, I had excessive problems with cold starting and saw no benefit in power. That is why I ask.

 

I agree it does burn cooler than gas. I think the reason a lot of people do it is for a safety net. When they start pushing the limits of the fuel it can become very volatile (speaking mainly from methanol experience here) and if your lean and detonation starts it can quickly become uncontrollable and cause a shitload of damage.

I would be using a BR7 on gas with the nitrous regardless, so I figured I would start there and see what happens on the E85

 

I guess that is what it comes down to.

I never understood why people lean E85 (or methanol for that matter) out as if it is gasoline.

 

In an ideal world you dont, but methanol is tricky to tune, at least in my experience in a high RPM 2 stroke.

If you dont lean it out to the point where it starts pulling clean, you have no benefit over gas. But you go too far, and **** gets ugly

 

what kinda two strokes are we talkin here... I've been flying model airplanes for about 10 years. Those little motors are fun I run a two stroke .91ci on 15% nitro, and a supercharged .91 4 stroke on 25%. Also have a little .25ci two-stroke that tachs 19,000 with a 7x6 prop. I haven't started porting those things though, lol just run more nitro!

 

fwiw, there's a local guy running .85 lambda on E85, claims that where he runs quickest. I'll start at .80 and go either way from there to pick up.

 

Yamaha banshee quads

 

I like MOAR spark, not less fuel. I was talking to another tuner who was considering installing a larger fuel cell on one of his customers SBF chassis cars. Seems it was using an entire 5 gallon cell worth in a single 1/8 mile hit on M5...

 

I like the correct amount of both