I first should say that I do not own an S2000 just yet but I am vigorously looking. I have owned and still own many Hondas (1 motorcycle, CR-V, 2 civics) so I know the reliability on Hondas are unmatched. I have been looking for something to upgrade from my 2004 Civic and have decided on an S2000. On the reviews it seems that the gas mileage of the S2000 is pretty decent for a sports car, but my question is every where I look it says that the S2000 is recommended to run on 91 premium unleaded gas, since the premium gas is so much more expensive then say 87, what damage would be done to the car if it was run on low octane gas. I will probably never ever run lower than recommended but I was wondering what will happen and if I will ruin the engine.

By the way this is a great forum and I have learned tons. I can

 

Yes, I would not recommend it. Here's an old thread from a while back discussing the topic. A search will turn up more info but this oughtta get you started.

https://www.s2ki.com/forums/index.php?showt...0&#entry1242610

 

lots. don't run anything lower than 91.

11:1 compression ratio.

 

The car can retard the timing to deal with 87, but I seem to recall reading that it dramatically increases wear on the engine, plus you risk pre-detonation which stresses the pistons and such.

Take your time finding the car you want for the right price. You wont regret it

 

Over the short term, in a pinch it is not a problem. If you get on the pedal or the weather is hot, the engine is more prone to knock (preignition). The engine has a knock sensor and will pull timing to eliminate the knock and then slowly, start to return the timing to normal settings until it detects engine knock again.

Folks with the ability to monitor timing have been reporting here that the S2K tends to pull timing a bit even on 91 octane.

One issue you would typically run into with 87 is that you would get crappy fuel mileage. Premium fuel is only 20 cents more per gallon than 87 so that is only a 5 to 7% difference depending upon where you live. Tests data I've read show that fuel mileage drops on the order of 10% or more when running regular fuel in a car tuned for premium so I would imagine it's really cheaper to run premium -- not to mention the power loss you'd get with the lower octane fuel due to the timing changes.

In a pinch, though, the manual does say that you can put lower octane fuel in the car. The best thing to do would be to put just a smaller amount in and then find another station with premium.

 

Wow, you're that much of a cheapass? At most stations I've seen premium (93 in my area) is 20 cents more than regular unleaded. The S2000 has a 13 (right? ) gallon tank which is $2.60 more per tank. If that $2.60 is too hard to part with at this time, the S2000 is not a car for you.

P.S: I don't mean to be an ass about it.

 

shell 93 vpower ftw.

 

Lower octane burns quicker, with such a high CR (11:1) you want something that burns slower (Higher Octane). If you have fast burning gas it can be completely burnt before the piston reaches TDC (Top Dead Center; the top of the stroke), when this occurs it is called "detonation" because there is incredible forces working against your engine and usually it leads to catastrophic failure. The knock sensor should adjust timing so that it all burns up, but not before reaching TDC.

I spun a rod bearing two years ago in my civic because of this, I was running 93oct but advanced my timing a bit too far and boom! (Well actually it was silent, but the aftermath wasn't).

Not an expert but did I hit the nail on its head?

 

Im not a cheapass. I actually have no problem at all paying for the extra 2.60. the reason i asked is because i have never owned a car that required a higher octane gas it was a simple question that i promptly got an answer too. I wasnt familiar with the compression ratio, if i had know that i wouldnt have even asked the question.

Thanks for all the helpful responses

 

yeah, premium all the way.

a much bigger expense is that you'll probably spend $400 on rear tires (assuming you get tires that are worth driving on) every 10-17k miles if you drive it like most of us.