Jfsram

I normally, no always fill my 93 coupe with 87 octane. It's all stock with cold air, long tubes, underdrives, 3.73's. Tonight the gas station was out of regular and only had premium at the same price.

My question is, has anyone tested at the track or on a dyno the power difference of 87 to 93 octane.

Bought the car in November and have not checked the ignition timing yet. I've floored it in high gear at low rpm and never heard it detonate so far.

93 LX FiveO

well.. these cars normaly run on 87 octane untill you start messing with the timing.

i run 87 in mine. ive used premium before.. didnt feel anything.

boost the timing and throw in some 93 octane.. you will FEEL the difference heh

deanzawistowski

FEEL?

subhumantat

if you advance your timing atleast 5* then you will see on a dyno around a 10 maybe up to 15 horse diff with the 93 octane, the real question is are you willing to pay the extra $ for the horse? I personally run 89 octane because you can get a little more hp for about the same $ as 87 octane

vt89gtvert

I am not sure that is a very effective HP increase though. If I ran 93 I would pay an aditional 25 cents per gallon (Roughly). So assuming two tank a week at 10 gallons apeice (I don't let my car get to low). Thats $5 per week. Times 52 weeks it's $260. I think I can find 10 HP for the same cost elsewhere. And that is just the first year. I have had my car for almost 8 years. Thats over $2000 dollars.

Jfsram

I hear you for the it's not worth it for daily driving. I've been on snow tires since November and ya, not really concerned about adding power right now.

It just threw some thoughts into my head. 87 octane for daily use and how much would you gain advancing the ignition timing and using 93. I was hoping for a number or time difference. Feel is hard for me to feel.

vt89gtvert

I have heard normally 1.5-2HP per degree you can advance the ignition. So with the 5 degree estimate above I would guess 5-10 HP or so. If that helps any.

SN95Stang

i run 93 octane in my car all the time....i used to run 94 but then sunoco stopped selling it.....i boosted my timing to 18 degrees and it made my car slower so now im running 14 degrees and it seems to b perfect..

88BlueGT

I run 89 octane and my timing is around 12-13. I gotta check up on that again... thanks for the reminder!