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av gas. Yes or no

DownZero

DownZero

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I have easy access to aviation fuel and wAs wondering if there is any benefit/downside to using it. Stock 383 4bbl. My thought was to mix it with 93 octane. Maybe help offset the ethanol content.
 
:popcorn2:

There is so much misinformation on 100LL Avgas. One thing you can count on is aviation fuel is top quality. Most of the time they will also have 91-93 unleaded with NO ethanol. I use the 100LL in my restored drag boat which has a 383/431 stroker and 10.5-1 CR.
 
If the 383 is stock and depending on the CR, 93 may even be a waste of money. Research shows that too much octane can hurt performance. Run the lowest octane without detonation.
 
DownZero said:
I have easy access to aviation fuel and wAs wondering if there is any benefit/downside to using it. Stock 383 4bbl. My thought was to mix it with 93 octane. Maybe help offset the ethanol content.
Click to expand...
90 octane non ethanol is the best we can get here and I mix it 50/50 with AV fuel. I add 4 ounces of Marvel Mystery Oil to every 5 gallons of AV fuel. All my 383's, 440's, and stock Hemi's run and perform great on this. 10.5 to 1 compression and less you are fine. I have a couple of 12.5 compression engines that run straight 110 or 115 octane racing fuel, no way around this.
 
One of my best friends has a close to stock 426 Hemi RR and he has used av gas for over 45 years. It just works.
Mike
 
I'm in AZ where my summer temps are 115-125 on average high. 383 stroked to 496 w aluminum heads n 10.5:1 CR. 91 octane and no detonation.
 
Ethanol free is the key, but on my 11.5 compression 383, 91 octane is the best available here. I mix 110LL AV gas at 2 to 1. It instantly fires, no hot start issue, and it just smells heavenly. I will also add 3-4 ounces of Marvel Mystery oil at the end of the season before putting it away for the winter. It is still the undisputed best upper cylinder lubricant.
 
I recall the addition of Marvel Mystery oil was a combination of top cylinder lubrication and it's supposed to keep the ETL (lead) emulsified. The important thing is reducing/avoiding or treating the ethanol. Ethanol sucks in engines, it has less energy and is hydroscopic. The only good use is over ice with a lime and tonic water.....
I add 1oz MMO per gallon 100LL Avgas. I haven't run into any plug fouling due to the lead. I run the boat hard. 4-5000 rpm for a few miles with bursts to 6400. 38º timing. It has aftermarket aluminum heads, but the other good attribute of lead is valve seat protection.

Life is short, burn the good stuff.:thumbsup:
 
BTW, whoever came up with the idea of add wintergreen to MMO was a f__king genius.
 
Have you ever checked with any bulk stations? Right downtown in my very, very small town I can take a drum in and but recreational fuel, 90 octane straight gasoline. I keep a 55 gallon drum of it at home for all of my small engines but one could store bigger bulks for their car.
 
I use that **** in everything! :thumbsup: Well other than the Kubota....
100LLtank 002.JPG
summer2020 387.JPG
 
$1.40/liter Canadian . I wonder how much that is Usd/gallon.?
I think I paid $22/5 gallons USD the last time, but it might have been less than $20.
Edit: I guess it's $1.60/liter after they ad sales tax on top of the other three taxes. Lol
 
I never understood easy access to 100LL and I have been pumping the blue for 35 Years at GRB

Same here 10.5-1 Compression 383/432 Stroker E Street 75cc Heads / Comp XE275 HL

93 Octane with 10% E or 91 Octane with 0% E

34 Degrees total timing zero issues

100LL made no difference and technically I can’t even buy the crap for myself and I am the damn manager
 
33 IMP said:
$1.40/liter Canadian . I wonder how much that is Usd/gallon.?
I think I paid $22/5 gallons USD the last time, but it might have been less than $20.
Edit: I guess it's $1.60/liter after they ad sales tax on top of the other three taxes. Lol
Click to expand...
Yep.. cheapest I've been able to buy it in years. Price/litre, NavCanada fee/litre, carbon tax now and then 13% tax on top of all the tax. $1.60/litre, basically 4 litres / US gallon.. so $6.40/gal/.75cents.. $4.80US/US gallon.
 
dadsbee said:
Yep.. cheapest I've been able to buy it in years. Price/litre, NavCanada fee/litre, carbon tax now and then 13% tax on top of all the tax. $1.60/litre, basically 4 litres / US gallon.. so $6.40/gal/.75cents.. $4.80US/US gallon.
Click to expand...
That's cheap compared to what we pay here - about $3.50 per litre for AV gas, and 100 Octane Race gas is roughly the same.
NZ$1.00 = CN$0.88 (today)

We get robbed down here...tax on tax on tax on tax, and GST on that tax.
 
dadsbee said:
Yep.. cheapest I've been able to buy it in years. Price/litre, NavCanada fee/litre, carbon tax now and then 13% tax on top of all the tax. $1.60/litre, basically 4 litres / US gallon.. so $6.40/gal/.75cents.. $4.80US/US gallon.
Click to expand...
Yeah, it looks like they have figured out how to tax the tax. Good racket!
 
My avgas in arizona is about thirty cents a gallon more than the 91/10% cat piss they sell in california.
100 no lead race gas is somewhere between $8.50 and $10 / gallon in cali. Ill use my avgas ,thanks.
 
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