I tried it once in my CRX about a year ago when I lived in Cali and it didn't seem to make anything go faster except my money. Now I'm starting to see it here in Vegas and was wondering if since my S2k has higher compression, do you think it'll make a difference? any comments?

 

isnt that the 3.50 a gallon stuff they sell at certain stations? Won't do anything IMO. I remember people that used to fill up at the airport with avgas( 100plus octane with lead). That CAN mess you engine up.

 

1FastS2k - You are correct.

Higher octane gas will not provide any power benefit unless your engine is designed for it. Many people don't realize that high octane fuel does not have a higher energy content. In fact, there is more energy in regular gasoline than high test (89 vs. 93 around here). The benefit of higher octane is that it "burns" more slowly and can be used in high compression engines (like the F20C) to extract more HP .

Also, there is more to gasoline than octane, and the additives in automotive fuel provide benefits that AVGAS does not.

 

I use it in my S2000 all the time. The only difference I notice that it won't bogg down when it's hot and I have the A/C on full blast. Now when I fill up with the 93 octane it will bogg down really bad sometimes and almost stall when I'm running the A/C. Thats just my experience.

 

I do ... Cuz mine is JDM and will drink nothing else less than 100 octane.

 

And how much is that 100 octane over there?

 

100 octane gas will not help much on NA cars, although on very hot days it will help avoid detonation and keep the timing where it should be, this means a few ponies at most.
On turbo applications, such as an S4 where detonation is more of an issue, and additionally with a modified ECU, 100 octane can really be worth it with a major gain in HP and TQ.

 

I have used 104 octane no-lead at the track on two occasions. In both cases I could feel what seemed to be a very moderate increase in sustainable power, especially as the track and the cars got hotter. It was a very minor improvement and in my opinion, on the street, it would not be worth the extra 2 bucks a gallon that it cost. However, on a hot track in July or August, it might get you past some of the cars that you would otherwise not be able to beat.

 

I believe this topic has been discussed in the under the hood forum at one time or another.

The high octane "racing" gas isn't just about octane. There are other benefits as well. For example, Unocal 76 100 octane (which you can buy at the pump in a number of locations in SoCal) actually has a much better formulation than regular pump gas. The composition is much more consistent and it is actually a faster and cleaner burning gasoline that leaves fewer end products (which can create combustion chamber deposits, or in the case of the wrong end gasses, promote detonation).

So, even if your car didn't need more octane to avoid detonation, good racing gas can provide benefits. It isn't worth the cost on the street with a normally aspirated car, but as others have pointed out, it may be on the track. Also, retuning may be necessary to extract maximum benefit (you might be able to run less ignition advance).

BTW, this isn't my take on it, this is information from the spec sheets on the gasoline and from a Unocal engineer.

UL