Just to add my opinion, but I have to agree with Slikness. I've worked in automotive repair for three years in SW Michigan and every winter vehicles come in with running problems. Why? Because the fuel the run in summer time is ok (87 octane 'cheap') but when winter time comes around that same gas does explode as hard and makes it harder for a motor to start. I can't even begin to count the number of customer's that have come back to me thanking me for my honesty and suggestion of running a higher grade of fuel. In a business sense, I wish that everyone had the same opinion as ivstang because that would be that much more business for me. Every customer that has heeded my advice on higher grade, better burning fuel has had much better results with there vehicles performance. Me personally, I'll only go to 3 brands of fuel....Amoco, BP, and Shell. Other than that, I will let my car sit instead of running some cheap crap through it.

TBirdGuy

"Stuck with a m*par, Settle for a ch*vy, Happy with a Ford!!!!"

 

That's sort of an ironic post because the lower octane fuel actually lights off quicker!!! Alcohol dragsters start with gasoline. I believe even top fuel cars either start with gas or alcohol to get 'em fired.

I have many articles from HOT ROD, CAR CRAFT and one of the best from HOT BOAT where a Mercruiser 502 made LESS power on supreme than regular.

I guess we will just agree to disagree.

 

It does light off quicker, but it doesn't burn off as efficiently, therefore making cold starting more difficult. Lower octane also causes more deposits on the valves and pistons. Have seen proof of this, customer brought in a car that ran good, up until he got it stuck in the snow and tried to get himself out and over revved the motor and spun a bearing. When the motor was disassembled, the amount of build-up on the valves and pistons was incredible.

TBirdGuy

"Stuck with a m*par, Settle for a ch*vy, Happy with a Ford!!!!"

 

[font size="1" color="#FF0000"]LAST EDITED ON 03-Feb-01 AT 09:30 PM (EST)[/font][p]I'll get my boots on now!!! LOL!!!

I'll try one more time to debunk this urban legend. The only diff in the fuels from the same brand is the anti-knock index, or the ability NOT TO IGNITE. This is accomplished by adding many different chemicals, one of which is Toulene.(you can do this at home for the adventerous) In fact a motor run on a higher octane fuel, if not completely burning the mixture, is more prone to carbon build up than if run on a "cheaper" octane. There is no magic "more explosiveness" or "cleaner burning" because of the higher anti knock index. Higher octane fuel burns slower....NOTHING ELSE,

C'mon guys, think about it. If higher octane fuels burned cleaner and more explosive and all this other mythical magical stuff, why wouldn't the EPA just make the "magic" higher octane fuel mandatory like when they banned leaded fuel?

Or here's a BIG question; Why wouldn't the manufacturers who STRUGGLE to squeeze EVERY LAST MPG for their CAFE ratings so they can sell more profit making, gas guzzling, SUV's and trucks just have ALL their cars run on premium to get their ratings up 10% or so? You all know how the CAFE(Combined Average Fuel Economy) works; right???

I'll ask my buddy from ARCO who is an engineer for them if I can release his e-mail. He is getting a kick outta all this though!

Peace, out.

 

I have taken several GCMS spectra of different grade fuels from different gas stations for classes in graduate school. The only difference is the anti-knock additives that make up the "octane" rating on the gasoline. These fuels look identical when you actually look at their chemical components. If your car runs better, so be it. Most people are wasting their money though.


Jason McCary


Research Scientist
University of Utah

 

the lead in race fuel is needed or not I run a 477 cu 629" lift 12.0 compression at 6500 on 112 trick fuel and it runs great