Who's running 91 and how far will it take you?
 

Hey everyone

A lot of great threads have been coming up that just add to the effectiveness and reliability that can be achieved while using water injection. So my question for you guys is, how many of you are stuck with 91 octane, what boost levels were you able to hit and does anyone know of the supposed "limit"? Previously it was the low 20's for 93 and water, and I'm just wondering how far 91 is/can be pushed. For myself, it seems that 91 and 50/50 is going to be my only route to squeeze power out of the little 13b - that or mix e85 myself :/. Thanks!

lmao, that was the link i was going to post too!

i've been talking to max for quite a while, and that car is very carefully tuned, a lot of time is spent on the correction maps (it makes different power on and off the dyno, different load, different temps).

Also very curious to know this as well, only 91 octane is available where I live and I'm planning to do a 50/50 meth injection as well.

Steve Kan used to say not to exceed 16 psi on 91, however I know I've probably spiked to more than 18 psi. My suggestion would be if you plan to run consistently higher than 16 psi on 91 that you add some form of "auxiliary" injection, i.e., water or water/alcohol.

this is an interesting topic, many oems now offer turbocharged engines that run on 87 octane. Anyone ever tried it on a rotary?

I would be careful to compare other cars to ours. piston engine cars have a cooling stroke. The new vehicles also have many years of development with their ecu control and engine knock retarding systems. I wouldn't take a new car and try to compare it to ours.

I run 91 here in CO and tuned mine to 17PSI, which is like 14PSI sea level. I don't have the need to go any higher as 14PSI sea level is a lot of power with my turbo.

yep.

16-17psi is a good safe point, 18+ you start having knock generally. you dont even need 50/50 meth kit. distilled water is great for knock reduction itself. dfoster154 is at 22psi 505hp with distilled water on a wannaspeed kit. im closer to 520rwhp @ 22psi running washer fluid.

and poor max is at 500hp with no water and 89 pump!