premium or unleaded?
Registered User
Joined: Dec 2001
Posts: 1,531
Here's what the 94 Camaro owners' manual says"
5.7 LT1 (Code P)
Use Premium unleaded gasoline rated at 91 octane or higher. You may use middle grade or regular unleaded gasolines, but your vehicle may not accelerate as well. The gasoline you use should meet specifications ASTM D4814 in the U.S. and CGSB 3.5-9.2 in Canada. Tehse fuels should have the proper additives, so you should not have to add anyting to the fuel.
[EDITED FOR COMMON SENSE]
Be sure the posted octane for premium is at least 91 (89 midgrade and 87 regular). If octane is less than 87, you may get a heavy knocking noise when you drive. If it's bad enough it can damage your engine.
If you're using fuel rated at 91 octane or higher and you still hear heavy knocking, your engine needs service. But don't worry if you hear a little pinging noise when you're accelerating or driving up a hill. That's nromal and you don't have to buy a higher octane fuel to get rid of pinging. It's the heavy, constant knock that means you have a problem.
5.7 LT1 (Code P)
Use Premium unleaded gasoline rated at 91 octane or higher. You may use middle grade or regular unleaded gasolines, but your vehicle may not accelerate as well. The gasoline you use should meet specifications ASTM D4814 in the U.S. and CGSB 3.5-9.2 in Canada. Tehse fuels should have the proper additives, so you should not have to add anyting to the fuel.
[EDITED FOR COMMON SENSE]
Be sure the posted octane for premium is at least 91 (89 midgrade and 87 regular). If octane is less than 87, you may get a heavy knocking noise when you drive. If it's bad enough it can damage your engine.
If you're using fuel rated at 91 octane or higher and you still hear heavy knocking, your engine needs service. But don't worry if you hear a little pinging noise when you're accelerating or driving up a hill. That's nromal and you don't have to buy a higher octane fuel to get rid of pinging. It's the heavy, constant knock that means you have a problem.
I used the economy and leaded stuff together once and I had to push my car home.
Registered User
Joined: Mar 2003
Posts: 1,411
From: Pelzer, SC
I do 93+ ONLY. I once put 92 octane in b/c that was all the gas station had and I didn't have enough gas to make it to the next one. But I want my car to run the best it can...so it's 93 octane and up for me.
Registered User
Joined: Jan 2004
Posts: 34
If the owners manual says 91, anything you use over that is a waste... and actually counter-productive.. Higher octane burns slower, and could actually make less horsepower. Higher octane is just more knock-resistant... If you run more timing, compression, or a different cam (which could affect compression), you might need it.. Otherwise, save your money
Registered User
Joined: Mar 2003
Posts: 1,623
From: Fairfield, ca
The manual says 91 is minimum. 93 octane is fine and is actually better. But if you live in Cali like me and others then the best your gonna be able to get is 91 octane. But definatly keep the unleaded stuff in there.