Leave this here...because I want to see what people with other cars say as well.

For two and one half years I would only put 91 in my CL. Thinking I had to. All this time my father (who works on cars for a living for about 35 years, and I decided not to listen to) was telling me 89 will be fine.

Well, for the last year now I have been using 89 in my car and I have driven cross country, I have gone to 150mph, I have floored it numerous times, and have accumlated about 25,000 miles on 89. Not one difference, not one problem with any pinging or anything.

So anyhow else still think they have to put 91 in their Acuras...anyone been using 89 the whole time.

 

89 will work fine here, because of the lower atmospheric pressure. The compression ratio of my first gen 2.5 TL I believe is 9.8 (correct me if I'm wrong). Until an engine reaches a certain compression ratio (like the new 3G TL that has 11.0 : 1 compression ratio), then you can use a lower octane. In my car 87 = bad fuel economy and sluggish response. I can't tell TOO much difference between 89 and 91. The third gen TL DEFINATELY has to use 91 octane. It's compression ratio is too high and predetonation will occur. To counteract this the ECU will adjust timing so that the engine puts out less power.

 

the compression ratio of the cl-s is 10.5:1 IIRC. is that high enough?

 

damn pga, no wonder your cars all fucked up, sounds like you beat the shit out of it lol

jk lol i think?

 

no, I beat the shit out of it the first two years of ownership...but no more than I beat the shit out of any other car I have owned. Alero, XJ8, 2 Jeeps.

 

what the hell! you have an XJ8?! why'd you get rid of that badboy

 

I put 91 because because I want the most power, good fuel economy, clean emissions (yes, I care about the environment), and a good running engine. The compression on the engine is already pretty damn high, using a higher octane fuel prevents pinging. I don't feel like hearing rocks being thrown in my engine. There are many factors around 91 fuel vs. The Rest.

 

Right... the CLS has a 10.5:1, but Tony has a CLP. That only has a 9.8:1 compression ratio...

Doesn't really matter tho', 'cause with todays modern electronics, if you put in lower octane then what's called for, the cars computer will retard the ignition timing so the engine won't detonate (or ping). The car will also have less power... Knock sensors are a wonderful thing, aren't they...

edit: I run 93 octane in my CLS.

 

Greenie...I have noticed no difference in performance
NiteQwill...no difference in Gas mileage
Sec...the XJ8 was my dads, he wanted to buy the XKR and I happened to wreck my car. So instead of getting me a new one he bought himself a new one and I drove his for some time. I wanted to take it out to college, but he said the service on it would be too much, and sicne he wasn't around to fix it for me...I better get a car under warranty.

when I had the CLS for 44 days I put 89 in that, no problems
and when I had the TL Loaner for 1200 miles I used 89 in that as well. (although I'm sure there were some slight performance issues in that.)

 

Well its a proven fact that higher octane adds performance to your car. What you think or feel in the seat of your pants while driving means nothing.

 

right but the difference in an Acura CL from 89 to 91 is meaningless

BTW. I understand how Octane works and all the revolutions in it throughout the years. I always did it because people on here said crap about pinging with 89 and for some reason I believed that.

 

I see.

 

You know physics...

"Seat of the pants" measurements don't count for shit. Empirical evidence is what we want. Dynographs, repeatable results, etc. etc...

From the 2003 Acura brochure:

 

I always use 93 octane, 94 if I can find it. But then again, i NEED 93+ octane in my CL-S to keep it from blowing up.

 

Meh.. depends on the car. Any mild J series engine should do fine with regular. Its the Type S models and '04+ TL and '05+ RL that really NEED premium.

The C and G motors NEED premium. Using regular is an emergency measure really.

 

well I have some "results"
I mean they aren't that "scientific" but 0-100 and 0-60 runs on my stopwatch compared to last year are the same.

Maybe its because its a CL and not an S...who knows.
My sister doesn't use it in her Mercedes and its supercharged but its only a 4

 

First Generation Compression Ratio for 2.5: 9.6:1 (I have the manual in front of me)

It reccomends 91+ Octane, for me 87 proves crappy results, 89 is alright, 93 is great. I usually mix back and forth between 89 and 93, depending on price and what I have in my wallet.

 

cl-s will run just fine w/ 89 octane. the ecu will adjust the timing if it sees detonation, but in turn you will lose some power. is it enough to notice?


i'm sure you would see it on a dyno though.

 

i have never put anything under 93 in mine

matt didnt u dyno your car on 89 and only get like 220 whp

 

Put filled up on 89 on a 04TL loaner i had, as the gas station was out of 93. ( during the hurricanes here in FL ), i got the same mileage as 91 and did not notice much of a difference at WOT.

But i'm sure it cant be good over the long term to be switching between 93 and 89.


For the CLS i only use 91-93

 

I've tried 93, there is now a grand total of ONE gas station in the entire metropolitan edmonton area that i know of that has 93. There was no fuel economy difference from 91, and I couldnt' feel a power difference. I feel more a difference when the air temperature is lower (but not below freezing) because the air is denser and its like pseudo-forced induction. I'm guessing the ambient air pressure is higher where you live so 93 might make a diff.

 

Our only options around here are 87-89-93, we don't get a 91 except at one station, but I used it for a few tanks and wasn't impressed for their price (their 91 was more expensive then Shell93 which runs better). I live in RI, not too far above sea level so I guess the ambient air perssure is higher. I notice a difference from 89 to 93, but usually have a mix in my tank, keeping it around 91ish.

 

I think that's the reason that 93 is generally not offered here. Air pressure.

 

Chevron Gas 93

 

93 octane here.

 

More specifically altitude. You'll only see 93 and 94 octane at sea level. I've seen 85 octane in Colorado and New Mexico.

 

I just tried my first tank of 89 and I plan on running 3 or 4 tank fulls before I make up my mind to do it for the long haul. I can't tell any difference in proformance yet. Will keep ya posted tho.

 

for the 3.0's it's been proven gas mileage and power is better w/ 87 vs 91

 

only 91 or more will go in my car. I noticed a performance difference when i made the test, and consommation is also a lot better with 91 octane, i got like 60 more miles par tank...

 

I have a '94 Chevy w/ a crapola TBI 350. That bitch gets regular unleaded.

 

ive run 87 in mine a few times to try it out and i got considerably worse mileage with it than with the use of 93. with all the driving i do (174,000 miles) ill stick with the 93

 

tpi

 

i wouldn't ever do it but if you say it works for you then
and we don't have 91 here, they force us to get 93 :P

 

If you fawks buy the difference in gas octanes from the pump, then I have some beachfront property in Idaho to sell. Do you really think 6 points means crap? Why can't you get the 103 stuff like the jokers in the 60's and 70's got?

 

Because leaded gas kills catalytic converters?

EDIT: And listen to your engine start pinging under load when you put in the cheap stuff. Honda's aren't too bad, but get a car that doesn't have timing retarding, and you should have a nice "chunk of change" sound.

 

Screw catalytic converters... biggest waste of money to comply with government regulations.
I still think unleaded gas could be made at 104 octane.

 

208 whp on a mobile dyno at the dragstrip. and i turned some slower passes (14.5-14.8)

next day i had 92 in it and was back in the 14.3-14.4 range.

 

Last 4 tanks of 92 mpg's were as follows
22.25
21.31
22.01
21.93
last 4 tanks of 89 were as follows
22.47
22.73
24.23 don't know how this happened. Same driving as other tanks.
23.21
I really did'nt change my driving style. Still mostly to work and back. Its about 65% highway and 35% city driving for me.
I guess On the next 4 tanks I will go back and try prem again.
The one thing that may have made a difference in the mpg's is maybe they went back to the summer blend. I did'nt really notice any proformance gains or losses between the two grades of gas. I have almost 10k in miles on the car now.