We have Vp racing fuel 104 octane for sale at our local track. I've never used anything higher than 92 octane, but I was just wondering... and does it make a difference?

 

I've used 100 octane before. The car sounded better, but didn't go faster.

 

110

 

I've run Chevron 94 with NOS boost w/Nitromethane which should bring it up a few points. 104 is killer! I've never tried that high - supposedly it can harm your cat (I run a straight pipe btw).

I've never really noticed any power difference but merely wanted to protect the engine from detonation during hard-use track sessions, hot weather and "just-in-case' I got a bad tank of gas. Cheaper than an engine rebuild.

I DO notice a distinct difference between 91 and 94 though.

 

Phatty R,

The only way gas will harm the cat is if it is leaded. If that is the case, you will foul your O2 sensor as well.

 

We don't have Chevron's here in Alberta, so 92 is the highest octane I can get. I've tried the 94 on my road trips and there isn't any difference.

 

92 is highest ever for my car

yoshi - who can only get 91 gas now

 

I've used 112 at the track.

 

My car run nice and strong in Van with 94 octane, but once I drove back to Alberta, I can only get the 92 octane garbage. I have to retard the timing by 3 degree to prevent detonation.
I think high elevation and low octane gas really don't mix well!!

 

high elevation is supposed to act as octane.
What kind of compression are you running that detonates so much on 92?

 

D and i were on Sunoco 94 plus a can of NOS octane booster for the track day...dunno what final octane equivalent was. Both ran like champs tho. leaded gas will ***** your catalyst

 

I am running around 11.3CR, JDM ITR engine with Spoon headgasket!!
but I think the problem is when I get my ECU reprogram, Yoshio said he can't program the ECU for 91 or 92 octane because of the high CR, so he programmed it for 94 octane gas!!

So I am running an ECu that programmed for 94 octane gas, but running on 91 octane!! My solution? Put a bottle of NOS racing formula octane booster in every tank!! No problem so far! I am too chicken to try a tank without it, so I don't know if it can run without it!!
When i said detonation, it happened when I advanced the timing back to to 15 from 13degree, I can hear some knocking sound at low rpm.

 

Are most additives leaded? I heard that the additives (octane boosters) can harm the cat/o2 sensors. There is a disclaimer on the label of the NOS stuff no?

 

Shell 93

 

100 Octane all day every day from the pump and 13.3:1 C/R Baby

 

Meathonal/alcohol, VP 18

 

I can tell the diff between Shell 91 and Sunoco 94 Octane. Sunoco all the way

 

I run Sunoco 94 octane for daily driver & 100 octane on occasion. You won't see an increase in performance running higher octane unless you advance the timing. Otherwise there's no performance advantage to running higher octane. I treat my ITR with JRSC to higher octane on occasion and a side order of advanced timing.

BTW, I've never had an O2 sensor problem using octane enhancers, but I have destroyed one with Fuel Injector Cleaner.