Gas :Super or Regular?

[Jeb]

It was my understanding that the computer (L98) will retard the timing if it senses a pre-ignition (knocking) problem, thus reducing performance but not injuring the engine.

Is this incorrect?

 

[Roadster Guy]

Both of us are happier with 94!

Sunoco 94 everytime...both of us are happier...especially with the LT4's higher comression.
RG

 

[Hrtbeat1]

It was my understanding that the computer (L98) will retard the timing if it senses a pre-ignition (knocking) problem, thus reducing performance but not injuring the engine.

Is this incorrect?

You are correct.

Not only pre ignition but detonation also. The sensor just picks up noise and tells the ECM to retard timing. Sometimes this can be a bad thing, a noisy tranny for instance, will trigger the knock sensor "False Knock."

 

[milehigreg]

Premium here too!

Don't you know that "Corvette" is French for "pay more"? More for insurance, more for parts and service, more for gas. Suck it up and put in the right octane. By the way, here in Colorado, premium is 91 octane. I have been told that it has to do with the altitude but but I can't quite get my brain around why.

 

[Achilles]

Premium or nothing. Seems like the highest octane I've seen out here in Cali is 91 or 92. I wish I could find some 94 someplace. How well does the octane boost work? I know a guy who runs regular in his vette and adds an octane booster additive to bump up the octane. He thinks he's saving money, but I think it's a wash buy the time you go to the parts house or Walmart, stand in line, pay for the product, add the boost & pump your gas. What did you save? Sounds like a big hassle to me just to save .20 at the pump.

 

[markone]

Not that I am advocating this for any vette, however my daily driver is a '94 Buick Roadmaster wagon, with the same exact drivetrain as the Impala SS (LT-1, true duals all the way back, etc.). The car has 160K on it now and I have been using 89 Octane in it exclusively for the last 80K miles. I periodically (every 6 mos) throw in a can of injector cleaner. I have not had a problem (it will probaly blow up tonight) with it and it runs like a raped ape. I also use synthetic oil in it. I still put nothing but 93 in my vette.

 

[jacob9582]

my manual says that the car will run fine on 87octane fuel, why would it be risky to run what the book says?

 

[tnovot]

my manual says that the car will run fine on 87octane fuel, why would it be risky to run what the book says?

Your crossfire '84 runs fine on 87 octane. You have a low compression L83 tuned for emissions and fuel mileage.
These other guys are talking about later model high compression LT1 and LT4 engines.

 

[jacob9582]

ah thanks for clairifying that, i understand! thanks!!!

 

[RonJ]

My stock 85 gets regular, I guess that's an 87 octane. I've never had a problem and I haven't seen any advantage when using "super". I throw a can of injector cleaner in once in a while. With the compression ratio in the 85 L98, there's no need for "super" in my opinion. For some reason, people seem to think because it's a 'vette, it needs high test. Baloney!! If an engine isn't designed for it, there is nothing gained by using a higher octane than is needed. You sure don't get more power simply because you're using high test in a low compresson engine. High test actually burns slower than regular, contrary to what a lot of people think.

My 98 on the other hand always gets the super. With the higher compression, you are losing power and maybe economy, 'cause the knock sensors are setting the timing back. Different engine, different fuel requirements!!
My two cents on this .... Ron ...

 

[WhalePirot]

Wowzers thats getting up there. Guess thats part of the secret to the 500 squared. ;worship I bet it does like the 100 octane.

True, and the aluminum heads allowed for the extra point of compression.

Boat= A large hole in water surounded with Fiberglass witch one dump's Bucket's & Bucket's of Money!!

I found it doesn't even have to be in the water! Apply this definition to an airplane, now.

 

[WhalePirot]

I think the CAGS Sucks!! What is it's usefull Perpus??

the Clutsy, Asinie Gear Shift? it's for C.A.F.E.

 

[craig0ry]

Thank god someone brought this up, but I mean I ran my '84 on 87 octane and it ran perfectly fine, even with the pedal to the metal. The c/r on these crossfires and l98's doesn't need 93 - but it is a valid point that it only sets you back, what, $5 max to fill it up with 93 vs. 87.

Also to whoever mentioned using 87 octane and it running like crap, then using octane booster in a can and "it ran fine"... I'm not sure one can of "octane booster" even raises you a full "point"...

 

[AUSSIEVETTEMAN]

Mmmm.....

On the subject.......stick with the premium fuel in the Vette. The question comes back to 'Do you love your Vette?'
Good fuel = good sense.

Off the subject, you guys have it pretty good with the price of premium. Our premium fuel is 98 octane and the regular is 93 octane. Prices range from between 0.98 cents per litre (about $3.68 per gallon) for regular unleaded to $1.17 per litre for premium unleaded (about $4.39 per gallon).

Our Vette runs on the good stuff, premium. We stick with Shell Optimax, it seams to run better and from what we are led to believe, it is a cleaner, denser fuel. I reckon they all say that!
All I know is every time I put BP premium in the Vette, the fuel consumption goes up and the performance down. If we can't get the Shell, it is Caltex premium.

Cheers

Tony

 

[ProEMTPFF]

Also to whoever mentioned using 87 octane and it running like crap, then using octane booster in a can and "it ran fine"... I'm not sure one can of "octane booster" even raises you a full "point"...

It was two cans of NOS "offroad" octane boost. They claim up to six or eight points a can.

 

[8388]

It was my understanding that the computer (L98) will retard the timing if it senses a pre-ignition (knocking) problem, thus reducing performance but not injuring the engine.

Is this incorrect?

The ecm in the L-98 is not as sophisticated as the OBDII, and although it does retard the timming some what when it picks up a knock, it will not save your engine under a hard load. I would not rely on the knock sensor/ecm to save the day. The extra cost of premuim fuel is well worth the insurance.

 

[cjs2]

I always use Super in mine. That is what the previous owner did and I continued with it. For as often as I drive it a few bucks extra really doesn't matter in my book. It certainly gets better mileage then my Explorer or Suburban (which both get regular) so it is justified in my mind..

 

[craig0ry]

It was two cans of NOS "offroad" octane boost. They claim up to six or eight points a can.

My apologies! I am just very wary of boost in a can

 

[MRANT212]

Enough of being concerned abou the $$$$ for gas... My feeling is that my Vettes are premium cars deserving of premium fuel...So that is what goes in the tank...PREMIUM

 

[JEFNLSA]

Throw 5-6 Mouth Ball's in it!! If you can get there Little Legg's Apart!! gmjunkie!!

BTW...Premium for me... PERIOD!