BV1

I was doign some runs this past weekend with 87 Octance and 92 Octane fuel. Just wanted to point out that with the 2.0L the Octane levels makes a noticable difference in acceleration. About .02 G's on the Gtech. Me and Jaws 01 raced a couple days ago, I had near empty tank of 87 Octance and he a half tank of 92, and subs. He pulled away hard in 2nd gear top end. Sad part is I have more mods, we both had CAI and Catbcak, but I had pulley and TB too... After, soon as I put 92 octane in, and raced him again, I passed him by a couple feet, edging ahead in the top end of every gear. Gotta port my IM.... :-)
-Steve

Viper966

octane rating does nothing to make ur car accelerate faster by direct cause an effect, the octane rating makes ur car ping less, if ur car doesnt ping ur ecu wont retard ur timing to cure the ping, so hence no ping = faster car, and dont forget the placebo effect

JAWS 021

Where both of you at the same rpm range?

Your mods??? do they consist of top end or bottom end???
some mods sacrifice one for the gain of the other,... hence the 2.5" exhaust

There are many variables when racing

J@WS 01

Octane does play a big role in power output. A low octane rating will cause the ECM to retard the ignition timing to prevent pinging, You now get less degrees of crank rotation on the power stroke. Advancing the timing will give you more push on the piston givng you more power.

BTW Steve I was using 87 octane that day wink

Viper966

if u read my post i said exactly what u did

BV1

hehe you would run 87 Octane in your baby? lol, hey did that gasket come in yet?

Stocker

I still say unless you have some nasties in your combustion chambers you shouldn't notice anything besides a placebo affect with hi-test.

NOBODY as far as I know has yet done a dyno test to prove it. NOBODY AFAIK has talked to the engineers who designed the ECU yet.

Your car will compensate IF THERE IS PINGING!!! If there is NO PINGING there will be NO COMPENSATION FOR IT!!! NOBODY KNOWS if the computer is designed to advance automatically until detonation.

I say they probably went the easy way and designed it to run 87 WITHOUT pinging, and if there is some pinging (for whatever reason) THEN the computer does something about it.

clear as mud?

BV1

Well, its like this, he beat me by alot, noticable power difference, I went and FILLED UP on 92 Octance gas, I beat him.

Clear as mud :-)

Neo_Tib

So what you're saying Steve is that it couldn't have had anything to do with driver and it was all on the full tank (extra weight) of 92 octane gas that you put in. Thats what attributes to you beating Alex? If thats the case when we went before and I stayed ahead of you I was running 87 ... does that mean if I ran 92 I'd blow the doors off of you?

I dunno ... I DO notice a difference when running premium ... but I also notice a difference when I drive without the 10lb spare tire in the back.

I attribute the minor differences in the hole shot hookup and shift timing (different torque bands etc)

BV1

Nahh you werent there, there were 6 ppl watching just ask around. Before I filled up he pulled ahead in every gear. I quite simply went down and filled up on 92 Octane, and bugged him to race again. We almost did a 1/4 mile. I was pulling ahead in the top end of the gears. Before he was pulling. It makes a difference.
Ask Alex.
-Steve