a retarded ECU huh?? was the retarded ECU's parents brother and sister?.....I'm guessing you mean having the timing retarded, which is done with the ignition....112 Octane is race gas, and you should really do some research on the meaning of octane....higher octane simply resists detonation at lower temperatures and pressures....since our engines arent high compression or FI, its a big waste of money, and actually if the fuel isnt detonating at the correct point(as it does with 87 octane), then it will leave behind carbon deposits and not produce as much power...why is this misconception so hard to debunk??????

 

My Honda Odyssey van can accomodate different grade of gas. In its brochure, it particularly states that regular unlead gas will produce 205 horsepower and premium unlead will produce 210 horsepower.

 

your Odyssey's compression ratio is probably high enough to produce better results with higher octane gas...doesnt mean it wont run on lower octane, since your compression isnt so high that it would cause early detonation, just isnt performing its best....but we are talking protege engines here, 9:1 compression

 

the copression ratio on a honda odessey is only 9.4 .3 more then our pros can it really be that different

 

well physics are physics...if that is tha case, to be honest Honda may be bs'ing those output claims...wouldnt be the first time a manufacturer did so....I do know that just to debunk this misconception, Super Street dyno tested a Honda civic that had 9:1 compression....no vtec, just reg honda engine...on 87 octane it made around 95whp peak...on 91 octane it made 93-94 hp peak....seriously do some research, take a physics class...WITHOUT HIGHER COMPRESSION OR FI,HIGH OCTANE NETS YOU NOTHING BUT A LIGHTER WALLET!!!!!!!

 

Don't forget that ignition timing plays a part. The Odyssey van may have a knock sensor and be able to advance the timing with higher octane fuel to up the power (which would reult in pinging or knocking with the lower octane). AFAIK, our Proteges do not have a knock sensor, thus the timing, compression, etc. works best with one grade of fuel.

 

i have seen other dyno test on other cars that show that they can get hp from higher octane and even the saturn dealership down the street uses premium only in the cars. they say the same thing that the infinity dealer says "it better for ur motot"

 

dealers don't know crap..I work with Mazda,Ford,Lincoln,Mercury,Aston Martin,Land Rover,Jaguar and Volvo dealerships....i wont waste any more breath on this...if you choose to waste your money on high octane gas without the compression to support it thats your decision to make...i guarantee that any car that you saw higher power from high octane was either FI or high compression...any American NA Protege without adding FI or higher compression than stock will not benefit from high octane gas, PERIOD..

 

The instruction manual of the Mazda MP3 has an addendum that Regular Unleaded can be used, but at the expense of the added performance that Premium would give. The MP3s ECU has advanced timing when knock is not detected (ie when higher than 87 is used). So either they're right, or they have an agreement with Exxon to rip us off.

Either way, I've been using premium for the last couple of years. I guess I can't really tell, so whatever. But I'm going FI in a few months anyhow, so there won't be any shocking increase in fillup prices

Chris

 

the MP3 ecu + premium gas yeilds 10hp to the crank (yes, it's true)...which really isn't much...but then again, it all adds up...which is why i'm putting the MP3 ecu in my P5.