I'll be running my rex at sears and I was woundering if like 2 gallons of 100 will male a diffrence I have K&N drop in 3" turbo back catless and up-pipe. What do you think

Peace and thanks Miguel

 

A higher octane rating will allow you to run higher boost safely. If you can, try to get some 100 octane on your way to the track. That way, you ECU will be able to learn the new fuel curve and make adjustments for it. It will take approximately 10 miles for the fuel to get through the entire fuel system and the ECU to get accustomed to it. Believe me, I have put a few gallons of 100 octane in my car at the track, and it did absolutely nothing, since I didn't give the car a chance to learn the new fuel. But now there is a gas station in Redwood City, which is on my way to Sears Point, that offers 100 octane. Actually this last Saturday, I filled up a half a tank of 100 octane at $4.19 a gallon.

Good luck at the track. I will hopefully be there in a few weeks.

Kurlee Daddee
(THE ORIGINAL)

 

If you are on the stock ECU, I wouldn't think that it is going to help a whole lot.

If you had a boost controller, and a bigger/better turbo, then you could pump up the boost safely.

I run 20 PSI on straight 100, but on 91 I only run 16. All that octane does is increase your knock threashold.

Good luck...don't break your transmission!

Andy