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Discussion Starter #1
If so do you run a top end lube or just filll er up and run er? Any problems with gumming up? need to run it out of gas at the end of the day or???
 

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In addition to the "lack of lube" thing, I'm told jetting will be different than with gas.
 
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I have been running av in my motor for the last 12 years with NO problems!No top end lube. No running it out at the end of the weekend! No gumming up NOTHING!Lots of people over the years have told me it hurts your motor thats total B.S!I also have a solid flat billet cam and run ONLY 60wt valvoline racing oil and the cam is still good!Also av is 100 octane low lead! But at sea level it's more like 110. I will continue to run it as long as I can get it.although my motor is 9 to 1 I dont have too I just do it burns cleaner and its not that much more that pump at the dock.
 

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I have been running av in my motor for the last 12 years with NO problems!No top end lube. No running it out at the end of the weekend! No gumming up NOTHING!Lots of people over the years have told me it hurts your motor thats total B.S!I also have a solid flat billet cam and run ONLY 60wt valvoline racing oil and the cam is still good!Also av is 100 octane low lead! But at sea level it's more like 110. I will continue to run it as long as I can get it.although my motor is 9 to 1 I dont have too I just do it burns cleaner and its not that much more that pump at the dock.
Hell if i can get a full season outta my motor id be tickled. Haha
 

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I have been running av in my motor for the last 12 years with NO problems!No top end lube. No running it out at the end of the weekend! No gumming up NOTHING!Lots of people over the years have told me it hurts your motor thats total B.S!I also have a solid flat billet cam and run ONLY 60wt valvoline racing oil and the cam is still good!Also av is 100 octane low lead! But at sea level it's more like 110. I will continue to run it as long as I can get it.although my motor is 9 to 1 I dont have too I just do it burns cleaner and its not that much more that pump at the dock.
Av gas must be different than race fuel then, because with a 9 to 1 motor you'd make more power on pump gas than 110.
 

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I have run 100% 100LL for 3 years now. 502 with 8.75:1 compression and 9 lbs. intercooled boost. Started off running Marvel but found it was not needed/waste of money.
 

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I have been running av in my motor for the last 12 years with NO problems!No top end lube. No running it out at the end of the weekend! No gumming up NOTHING!Lots of people over the years have told me it hurts your motor thats total B.S!I also have a solid flat billet cam and run ONLY 60wt valvoline racing oil and the cam is still good!Also av is 100 octane low lead! But at sea level it's more like 110. I will continue to run it as long as I can get it.although my motor is 9 to 1 I dont have too I just do it burns cleaner and its not that much more than pump at the dock.
Where do you buy it ?

Are you just running it because you think the super at the dock would have water in it ? :)bulb At 9:1 if they have premium that would be more than fine and it will make more power with a 91 octane gas. IMO

Sleeper CP :D
 

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I've been working with it for years in all sorts of engines, never an issue or problem to date due to the fuel.
The only tip I have is that it does run leaner, so jet up a little until you find the sweet spot, read the plugs!
Also if your running an electric pump that is not designed for use with alcohol such as a standard Holley blue, you will need to put a little top end lube in the fuel to keep the pump alive, otherwise you will find that it locks up, or runs real hot.
BTW running a higher octane fuel like AV in a 9.5:1 or less combo is a waist of HP and money, the engine will make less HP in most all cases.
 
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A crop duster! Yes I run it because it burns cleaner and I never worry about it being bad.My motor runs cleaner with it but I can assure you I don't lose or gain any power and its cheaper than 91 at the dock in the summer.Now sleeper I know you have somethin to say so come on spit it out! How am I losing by running it in my little 9 to 1 motor????
 
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I've been working with it for years in all sorts of engines, never an issue or problem to date due to the fuel.
The only tip I have is that it does run leaner, so jet up a little until you find the sweet spot, read the plugs!
Also if your running an electric pump that is not designed for use with alcohol such as a standard Holley blue, you will need to put a little top end lube in the fuel to keep the pump alive, otherwise you will find that it locks up, or runs real hot.
BTW running a higher octane fuel like AV in a 9.5:1 or less combo is a waist of HP and money, the engine will make less HP in most all cases.
It's cheaper than 91 octane in the summer! And I run a clay smith manual fuel pump.Btw 91 was 5.00 a gallon at the dock last summer.and it could possibly have water in it! or just be bad that is why I run av:)devil
 

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A crop duster! Yes I run it because it burns cleaner and I never worry about it being bad.My motor runs cleaner with it but I can assure you I don't lose or gain any power and its cheaper than 91 at the dock in the summer.Now sleeper I know you have somethin to say so come on spit it out! How am I losing by running it in my little 9 to 1 motor????
Fwiw typically a higher octane fuel burns slower. So best results(power wise) come by running only what you need ,plus a little extra for safety/peace of mind. I know I'm not sleeper:)grn but 3 peeps told you the same thing.
 

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What the Hell is That?
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I do a 50/50 combo 91/AV

motor is 8.1 on 5lbs of boost.
 

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Boat Nut
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We found in a 10.5-1 comp Ford 500 incher, we make more power on pump gas and less timing than AvGas and more timing.
 

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What the Hell is That?
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I was always told AvGAS helps control pinging and detonation.
 

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We found in a 10.5-1 comp Ford 500 incher, we make more power on pump gas and less timing than AvGas and more timing.
Sounds about right. :)

The second generation of the 565 ( Gen.1 780 hp, Gen 2 855 hp, Gen 3 935hp) was on the dyno and after it made 855 on VP I put a blend of Av gas and 91 in the tank ( 2 parts Av 1 part 91) it made 5 hp less all the EGT probes read about the same and I didn't change the jetting.

I ran Av gas for years in the boat (10.8-11:1 comp and 250-300 hp Nos ) never had a problem and I'd still run it at 12:1. We always blended it at 2:1 with pump gas to keep the fuel pumps and hoses happy ( 10 gal Av gas 5 gal pump gas in out large Jerry jugs)

Sleeper CP

Big Inch Ford Lover :D
 

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A crop duster! Yes I run it because it burns cleaner and I never worry about it being bad.My motor runs cleaner with it but I can assure you I don't lose or gain any power and its cheaper than 91 at the dock in the summer.Now sleeper I know you have somethin to say so come on spit it out! How am I losing by running it in my little 9 to 1 motor????
That's the best reason; piece of mind. Just so you don't think you're gaining any power. :)

Sleeper CP :D
 

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Amber Racing Services
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Av Gas ... I've posted this before & will again here ... a lot of people will run it and love it, but is it giving you all the power you could have on the water? No, probably not. Will it work? Sure it will.

Educate yourself and then make your decision ...

I wouldn't substitute Aviation Gasoline for racing gasoline unless your race engine operates in 7,000 - 10,000 feet of altitude, and does not exceed 2800 - 3000 RPM.

Many people see Aviation Gasoline (AvGas) as a way to reduce the cost of their operation. This may be true, but if you want the most out of your engine and want to avoid problems, AvGas may not be your first choice. AvGas is a good gasoline for low speed aircraft engines that run at 2700 to 3000 RPM at 7,000 feet or higher.

This does not mean it is a good gasoline for high performance engines operating at 4500+ RPM. (AvGas is also illegal to use in anything except aircraft engines. Violations can carry a potential penalty of $25,000 per day of violation. But they still sell it at the river and no one ever gets busted)

AvGas octane numbers are determined in a different test than motor gasoline octane numbers. Do not be confused by the big numbers from the AvGas test method. They are not comparable to motor octane test numbers. Most 110 race fuels tests at 160 on the AvGas Scale. AvGas is held to tighter requirements than street gasoline.

Some gasoline blenders use AvGas as a blending component to save money. AvGas has a lower specific gravity than most racing gasolines. This means that if a person tries AvGas and has not re-jetted and adjusted their floats, he can burn a piston because the air-fuel ratio is too lean and/or the engine detonated. To make a good comparison between two gasolines, the air-fuel mixtures must be the same. Even after re-jetting, one could experience burned pistons with AvGas if the Motor Octane Number (MON) is lower than what his or her engine needs.

Another potential problem with AvGas is that there are several different octane grades. The 80/87 grade is red in color and can get you in lots of trouble because of its very low octane number. The 100LL is blue and the 100/130 grade is green. Both of these have much lower Motor Octane Numbers than most racing gasolines and will detonate when the engine octane demand is greater than the octane number of the gasoline.

Make sure you do your homework before running AvGas or blending with it.

Before some go sideways and flame out on me ... I'm just posting this so those who are looking at it as a viable option, they hear both sides.
 
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If so do you run a top end lube or just filll er up and run er? Any problems with gumming up? need to run it out of gas at the end of the day or???
Did not want your thread trashed! I thought you asked for REAL opinons try it youll like it! Then come back on here with YOUR results!There is Absolutely NO noticable power loss It burns cleaner it smells better! But hey YOU be the judge!
 
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