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Discussion Starter · #1 ·
Just wondering if regular will harm anything? Had to buy a tank of regular yesterday as they had no premium. Seemed like the bike had more power. I know regular burns faster than premium so that stands to reason. What are the issues though? Will I start burning exhaust valves or something?

Thoughts?

sb 355 zz4 fi
 

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No pinging or knocking...no problem. Your timing is, obviously not as advanced as mine or you accelerate less briskly. Regular gas doesn't burn faster but ignites at a lower compression than premium. It won't burn any valves or hut your motor if it is not producing detonation (pinging/knocking)
The heat produced by compression can get the regular to ignite before the plug fires producing pre-ignition or pinging/knocking. If you have no knocking /pinging you are doing no damage to your motor but your feeling that the bike is faster with regular is just not rational and is in your head...not reality. Once combustion happens the power is the same, ie, the mixture burns...period!...Joe
 

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I agree with Joe. That if your engine is not knocking or pinging you are fine with the lower octane gas.
On the flip-side I am thinking about mixing aviation fuel (115 octane) with 93 octane. I know the engine will burn hotter, but I am expecting improved results, not that I need any more!

Dave in Columbus
 

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Contrary to widespread belief, the octane rating doesn't indicate how much power the fuel delivers; all grades of gasoline contain roughly the same amount of heat energy. Rather, a higher octane rating means the fuel is less likely to cause your engine to knock or ping. Knock, also known as detonation, occurs when part of the fuel-air mixture in one or more of your car's cylinders ignites spontaneously due to compression, independent of the combustion initiated by the spark plug.
This little quote was taken from:

http://www.straightdope.com/columns/041008.html
 

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Discussion Starter · #6 ·
Ok, so I was partially right. Regular burns faster.

Even when I burn premium, I will get a small knock or ping sometimes at moderate acceleration. Hard to tell where it's coming from but it seems right out of the battleship just in front of my seat. If I accelerate harder, it goes away. Could that be a detonation ping, or would it be there at heavy throttle too?

The tank of regular I was referring to earlier had no knock at all. The weather was a bit cooler and I had just realigned my drive belt, all of which could account for more mental horspower.

I had a 350 hp sb in my 1976 Silverado years ago with 10:1 flat tops in it. I put on thousands of trouble free miles on regular. I just needed to hear it from you guys. Thanks
stu
 

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Bottom line here if the engine is not designed for it you will not see gains but it will make you feel better :D . My engine was designed to run on 94 and all we have in Texas is the 93 so I spike mine with a little 116 Trick leaded!!!! It smells better and the inside of the pipe is white!

These big motors esp with the loud pipes makes it hard to hear a ping would everyone agree at least it does on mine?
 

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crazymf said:
Just wondering if regular will harm anything? Had to buy a tank of regular yesterday as they had no premium. Seemed like the bike had more power. I know regular burns faster than premium so that stands to reason. What are the issues though? Will I start burning exhaust valves or something?

Thoughts?

sb 355 zz4 fi
I would like to burn Regular and save .30 cents a gallon but with 10.2 to 1 compression you are asking for a problem. The engine compression calls for 91 to 92 octane and can be detonating under slight to heavy loads (providing you have the timing up where it belongs) and you can't hear it. Pinging will cause the ring glands to compress and freeze up the rings. That will cost much more than the little you pay for the higher octane. Call the local Chevy dealer and ask the service mgr if it is O K to run regular with the compression we have. You can set the timing back 4 to 6 degrees and maybe get lucky but you will sacrifice H P but I guess that is O K to.

Just my .02 cents

Adrian
 

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I saw a Discovery Channel show on this subject about 1 month ago and learned that the more Octane in the mix, the more the fuel can be compressed without it exploding. The less the Octane the less compression can be used on the fuel.

This means that on a higher compression engine you need a more stable fuel to prevent the fuel from igniting prematurely. More octane gives you this.

Sorry, I didn't read the article from the link posted above. I may have just repeated something.
 

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Discussion Starter · #10 ·
40 grand for the bike. I can afford the fuel. I'll stay with premium to be safe, but won't worry too much if I have to put regular in once in a while.

Thank you guys.
stu
 

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Discussion Starter · #11 ·
Just found out that my fuel injection has anti detonation, which means it won't ping or knock because it will change the timing to compensate. So, premium all the way for me.
 

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Crazy...This anti-detonation thing is simply a computerized way of retarding your timing and robbing you of power. For god's sake, a high compression engine simply needs high octane gas so that it doesn't detonate (explode) due to the inherent heat of compressing the air/fuel mixture before the plug fires.
This is not rocket science!! Octane is simply an eight carbon chain molecule that retards combustion from prematurely occurring.
JEEZ...the few cents you save on regular, why take the chance.
Really...let's put one thing to rest, AGAIN: Neither regular nor high test produces more power than the other upon ignition. Higher octane DOES NOT MEAN MORE POWER and regular DOES NOT BURN HOTTER OR FASTER THAN PREMIUM!!
Once the mixture burns it burns with the same heat and power regardless of octane rating....Joe
 
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