If my car got tuned for 91 octane, will I get any benefit using 93+ octane?
Thanks in advance

 

yeahhh bumpin old thread. I have similar questions.

I have a 91 oct tune:

1. how much hp am i loosing over a 93 oct tune? (uicp, intake,mbc,flash)

2. is it at all possible i am running into problems as a result of ALWAYS using 93oct on a 91 oct tune?

I didn't choose a 91oct setup and it is hard to find anything but
93 around here. I assumed it wouldn't make a difference but i am starting to
question the power of the car (no i'm not just getting use to it). Could i be slowly hurting sensors by running the higher oct over a long period of time ...or ....? Sorry for this newb question that i think already know the answer to haha.

 

If you cars were tuned properly for 91 it won't hurt to run 93 but you probably won't see any benefit. A retune should help get some more HP though, more timing is a good thing.

 

What do you mean you didn't choose to get tuned for 91?

 

If you are tuned for a lower octane fuel then running a higher octane fuel will be no benefit in power. The higher octane fuel is slower burning and if anything could decrease your power since you are not tuned for it. You shouldn't hurt any sensors unless you run leaded fuel like C16.

 

+1

 

+1

 

a 93-octane tune wil give you about 20WHP over a 91 generally.

 

As in I bought the car with a tune already done. If it had been up to me, i would have done it for 93.

Does anyone else agree with cssaddictm4?

The reason i ask is that my 1/4 et's and mph are higher and lower than a friend's stock nine even though i'm running better 60' foots him. I've tried many different types of launches/shifts etc and still only manage ~ 101 in the 1/4. I thought i was having clutch problems, but it doesn't seem to be slipping like a typical going clutch does.

 

LoL maybe ur friend is just a better Driver .. USDM Evo IX Manuel says Stock IX should run on 93 but 91 is safe but power is not the same...my IX feels slow when I drive it every day... then sit it for 3 or more days sometimes then drive it and it feels like GOD ! lol

 

I have actually asked this question in the past. I accidently got my mail-in ECU flash for 91 octane when I fill it up with 93 octane (a brain fart on my end). I think I am running rich because of it. I am looking at getting a new e-mail flash to bring my performance additions to proper specs. I feel like I am hitting a wall when I get the revs above 5k.

 

so, could a stock evo (with its stock 93 oct setup) be making nearly as much power as an evo with my mods is making with a 91oct tune?

 

No way. Try 40-50 hp difference, at least where I live in the midwest. I had a car tuned down in TX on my 91 octane. There was a car almost identical to mine in mods getting tuned on 93 the same day, and he ended up making 50 whp than me. There is a big difference between 91 and 93. I had two seperate tuners telling me that our 91 here was horrible so maybe its just where I live, but I kind of doubt it.

 

93 octane(R+M/2) is 93 octane, irrespective of geographic location. There is a difference of two octane numbers between 93 and 91. Given the same engine operating at similar ambient temps and altitude, those 2 additional octane numbers will let you run about 2-4 PSI more boost, which on a DOHC 2-Liter won't produce an additional 40-50 WHP with the stock turbo. At least, I don't think so!

 

yeah, there's no way there will be a 40whp difference. I'm even skeptical about a 20whp difference.