mAnYsTyLeS

No real answer to this on this forum (that I could search for). Thanks for your time.

Daniel60

I run the Brenspeed 93 tune in the winter and I run the 91 octane tune in the summer. The 93 tune pings in the summer the 91 doesn't on 95 percent of the time. I run 93 octane all the time. Ouch!

billybix76

I dont think safety is a concern with either tune if adjusted right. I started with Brent's 87 tune. then tried his 91 tune when i got a tank full of 91. Like it better. I get better milage on 91 than 87 (+2mpg) that offsets the higher cost per tank and if pinging or preignition is a concern adjust the tune WOT percentage -+2% either way whichever feels better and retard timing in each rpm range a bit( -1 degree at a time) . then you should be able to run the higher octane tunes all year. Thats the good thing about the XCal II from Brent. you have all the user adjustables... Brent also answers his customer's email asap at tunes@brenspeed.com

Mudflap

I run the 91 tune on mine even though I can get 93 gas because I didn't notice a significant difference between them. Also, even if I drive to an area that doesn't have 93, they're going to have 91 at a minimum. IMO the 93 gives you less of a safety net in terms of variability in gas you might purchase from any 1 location. When I've run tunes in the past on various cars that are right on the maximum octane available in my area, I've ALWAYS had situations where I get random tanks of gas that causing pinging, etc. I had a list of gas stations scribbled onto a piece of paper in the glove box of my WRX that were on the ban list for causing issues, and that car was tuned by Cobb Tuning who is known to be conservative.[>:]

Boss919

I've tried the 93 tune and his 87 tune. I stayed with the 87 octane tune just because it save a little more money when I fill up, and I feel I'm not running the car too hard every day. But as soon as the Drag way opens, 93 octane and tune will find its way back into the car.

mAnYsTyLeS

Good point.

acascianelli

So would it be bad to run with a 91 or 93 octane all the time? This thread is making me think twice about getting a tune myself.

howarmat

I have been running a 93 tune for more than 6 months no problems at all. I beat it regularly.

mAnYsTyLeS

That's why I'm asking. I kinda feel like, if the car was built for 87 then it should be safer to run 87 then 93 all the time. It could be just me though....

Boss919

Run what you want, as long as you don't have any ping issues you should be fine. Its not harming your engine to run the 93 tune.