Has any body been using 40 % nitro fuel?
What Fuel do You use and why?
I use Byrons 30% original. I seem to maintain a long life out of my engines, but I have been wanting to try the 40%. Any one have any input?

No. In fact I haven't seen anyone, that's fast, run an engine that was anywhere close to making max power.

Everyone seems to be running restrictors around 7mm and 3-4 port mills like the +4 and OS XZB. Haven't seen a powerhouse like a 7 port RB WS7III with a 8mm restrictor in a while.

Run time and smooth power are currently trumping pure power output. You can also get slightly better mileage with 25% nitro. But for whatever reason 30% Sidewinder and Byrons works best for me.

If I had it my way I'd allow larger fuel tanks that way maybe some racers would opt for more powerful setups to kind of shake things up some. everyone running the same engine kind of bores me. I love seeing small .19 race mills going up against gas guzzlers like the .28xz etc.etc. Variety and unpredictability are the spice of racing.

I have only used 40% and watched others use 40% in Nitro Dirt Latemodel oval racing. I have found it hard on the engines as well.

40% isn't horrible for your engines , just maintain enough castor oil in your fuel , add 1.5 oz to byrons 40/9 for extra protection

1.5oz of byron straight castor or the lube booster?

lube booster is castor

For nitro fuel...

tons of the top pro's will run 40% nitro..... happens all the time these days.....ever wonder why some of the Pro's stock engines run soo strong ? sometimes they will run even higher nitro then 40%

Can't you go futher down in oil, when you use 40% nitro? I would guess 8% would be just fine

I thought high nitro % 40 is used for high elevation places.

Hehe. I remember back in the ´80: Some Italian drivers ran 50% nitro AND drilled their Picco engine up to 3,8 ccm insted af the legal 3,5...