I know, silly question, but I was wondering which gas is best for the Fiero...Should I use "super-dooper ultra premium" or just "The regular stupid crap"?
I'd rather use whatever is better for the engine...it's an 88 V6...
Thankx!

-FR

quote Originally posted by FieroRumor: I know, silly question, but I was wondering which gas is best for the Fiero...Should I use "super-dooper ultra premium" or just "The regular stupid crap"? I'd rather use whatever is better for the engine...it's an 88 V6... Thankx! -FR

I use 89 octane "gasohol"--in Iowa, the 89 octane "gasohol" costs the same as the 87 octane stuff without ethanol. (Otherwise I'd be using the 87 octane stuff...)

I don't believe these cars have octane requirements. You ought to be okay using 87.

Ed

If the engine is stock and in good condition the standard 87 octane is fine. Using a higher-than necessary octane under those circumstances is strictly a waste of money, you won't get better engine performance or gas mileage simply by using higher-octane fuel.

If you've made hot mods to the engine or if you have problems pinging you may need to use a higher-octane gas.

I read awhile back, that the 2.8 required 92 octane due to the HO heads. This was in road and track (or was it car and driver) back in the 80's. But from what I understand the HO heads aren't any higher compression, just larger valves, so I'd wager a good 87 Octane is just fine. Just my $.02 though.....

Pontiac originally recommended using 87 octane in the Fiero of all years and engines.

Phil

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GTDude
25 years GM experience

well i use 95, here the lowest is 92 octane. well that's europe.

edit: btw i run a miller&woods turbo, 0-30W oil gives me good oilpressure.

hans

[This message has been edited by 86 gt fastback (edited 06-28-2002).]

quote Originally posted by 86 gt fastback: well i use 95, here the lowest is 92 octane. well that's europe. edit: btw i run a miller&woods turbo, 0-30W oil gives me good oilpressure. hans

Hans -

The US and Europe use different methods to rate octane levels.

You use what is known as the RON (Research Octane Number). In the US we use what is known as the CLC (U.S. Cost of Living Council Octane Rating), which is the average of the RON and another value known as the MON (Motor Octane Number).

87 Octane here is the 'regular' or 'standard' grade and would be roughly the same as your 91 octane gas.

Our 'premium' or 'high test' generally has a CLC rating of 91-93 depending on the vendor and is about the same or a bit better than your RON-rated 95 octane gas.

Since you've got a turbo you're wise to run with 95 octane.

Just to be on the safe side, I use JP5 in all of my cars...

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87' Fiero GT 5-spd
84' Fiero SE 2m4 4-spd, FOR SALE!!! $400 w/o replacement engine, $500 w/ engine.

Use the cheapest stuff that doesn't make your car ping!

Might be a good time to read your owners manual if you have one. If my memory is correct I believe it reccommends 92 or 93 octane with the 2.8 engine.

Mike Murphy
DSM PMD
Portland ZOne 84-87

My timing is advanced 12 degrees. I run 92 all of the time (never put anything less in it the entire time I've owned it.) Is this neccesary?

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^{The Black Beauty (85 GT) - Bustedato (86 SE, Parts car)
Don't sweat the petty things, and don't pet the sweaty things
AOL IM: KSSouter
MSN IM: I_R_Sootah@hotmail.com}

quote Originally posted by Mike Murphy: Might be a good time to read your owners manual if you have one. If my memory is correct I believe it reccommends 92 or 93 octane with the 2.8 engine. Mike Murphy DSM PMD Portland ZOne 84-87

91 Octane using the RON method.

As I mention in my earlier post this corresponds to 87 octane fuel as sold in the US.

Before I got rid of my 1984 SE I tried regular (87), midrange, and premium in it in
an effort to get rid of the pinging on hills.
The only one that got rid of the pinging was premium.

my bored and stroked 2.8(3.2) with ported and opened exhaust runs quite happily on 87 octane. err Gasohol, what ever you call it in your part of the mid west. It's cheap, it's plentiful, and not a single bad peep from the engin.

-Rick

...from my onwers manual..."You should use unleaded fuel with an octane rating of at least 87."

"Your gasoline engine is designed to use regular grade unleaded fuel that meets ASTM D 439 (CGSB 3.15-M87 in Canada) specifications."

Tim

Mine pings on JP5, I use JP7 just to be safe ;D)

I do have to inject some Tri-Ethel-Borane on startup though...

Best!
Ben.

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Ben Cannon
88 Formula, T-top, Metalic Red. (2:13.138 at Sears Point) "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver, In-Progreess. -Mel Gibson, "Braveheart"

What exactly does this pinging sound like? I don't belive that I've ever heard it. I owned an 85 Cavalier b4 this, so it didn't matter what gas it had in it, and I've never put less than premium in my 85 GT.

quote Originally posted by Sootah: What exactly does this pinging sound like? I don't belive that I've ever heard it. I owned an 85 Cavalier b4 this, so it didn't matter what gas it had in it, and I've never put less than premium in my 85 GT.

It usually sounds like a light, rapid rapping from the engine. If you've got the problem you'd commonly hear it at highway speeds when gently accelerating without downshifting or if going up gentle inclines without stepping on the gas. It used to be a lot more common when unleaded gas was first widely sold.

You get the pinging because the gas mixture in the cylinder is pre-igniting, if you're using really substandard gas (not a problem in the US or Canada) you can cause serious damage to your engine. That's why GM puts (or, at least they used to put) disclaimers about needing to have the engine retuned if you'll be driving outside of the US or Canada. Octane in the gas reduces the likelihood of pre-ignition, and at least at one point some parts of the world routinely sold gasoline with lower octane ratings than typically found in the US.