Saturday Night Racer - 110 octane race fuel or pump gas?

dirt33 LMR Senior Offline Posts: 265	110 octane race fuel or pump gas? 01/23/11 at 9:06am When running in a Hobby class with a 9:1 350 and a Rochester 2 barrel, will using 110 octane gas accomplish anything at all over 93 octane, or is it simply a waste of an additional 5 bucks a gallon over the pump gas? I've heard opinions on both sides of the equation. Just interested to hear what you guys think. Thank you.
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over4t

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Re: 110 octane race fuel or pump gas?
Reply #1 - 01/23/11 at 10:01am

Waste of money. Generally if your running 9 -91/2 engine you'll be fine on pump gas. We've run several engines like that over the years, tried both pump and 110 and saw no difference and the engines lived. Just like a street car, running premium in a car that calls for regular only lightens your wallet. But stay away from the generic no name gas stations. Stick to the Chevrons, Shells, etc.

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Andrew

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Re: 110 octane race fuel or pump gas?
Reply #2 - 01/23/11 at 4:16pm

I don't know my compression ratio (never calculated it), but I started with a 9:1 engine and shaved .050 off the head, and I run 93 pump gas with no problem. I used to run race gas, 104 I think, but switched to pump gas 3 or 4 years ago. It's easier to deal with filling up too. Just pull into the station and fill 'er up. No more fuel jugs.

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Dietzsch_Racing25 LMR God Offline Posts: 995	Re: 110 octane race fuel or pump gas? Reply #3 - 01/24/11 at 9:49am I agree. With 9-1/2 compression it is completely unnecessary. CD
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harley83 LMR Member Offline LETS DO THIS! Posts: 202 los banos, ca	Re: 110 octane race fuel or pump gas? Reply #4 - 01/24/11 at 11:08am you can get 100 unleaded out of the pump in los banos lol... heres a link it has all the gas stations that have it at the pump... http://www.davebarton.com/Unleaded_Racing_Fuel_in_SoCal
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over4t

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Re: 110 octane race fuel or pump gas?
Reply #5 - 01/24/11 at 3:30pm

Harley, that's good to know if you're out of town and can't get fuel at the track but it sure is pricey. Most tracks up here we get 110 or 112 Sunoco at the track for $7-8 a gallon. Paying more than that for 100 or less seems excessive. Dirt 33 and other low compression cars still don't need other than standard pump gas. Another $5 or$6 bucks a gallon over a season sure puts a crimp in the old budget and could get you some tires/shocks or whatever and make a real difference in how you run. Or splurge and take your volunteer crew out for a steak after a good night at the track.
That's always appreciated and will come back to you 100 times over.

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sj_valley_dave

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Re: 110 octane race fuel or pump gas?
Reply #6 - 01/24/11 at 4:06pm

All the higher octane does is slow down the flame travel in the combustion chamber. A very high compression engine will "pre ignite" with too low of octane and the combustion basically is out of control. The high octane slows done this combustion, so if you do not need race gas, and 9.5:1 does not need it, you will actually see a decrease in power if you run an octane that is higher than you need. You will slow done the flame travel in thechamber and hurt power....That is why they have so many different octanes...You need to run the level that suits your engine....

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dirt33 LMR Senior Offline Posts: 265	Re: 110 octane race fuel or pump gas? Reply #7 - 01/24/11 at 4:56pm Thanks for the help/ideas.
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