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10% toluene mix with 91 octane

7K views 17 replies 10 participants last post by  dave420 
#1 ·
i've recently tried an experiment with 10% toluene and 90% 91 octane... the 380se runs MUCH smoother at idle, and doesn't vibrate until i hit the mid 4k's.
it used to vibrate when i reached over 3.5k rpm. (the mix creates about a 94-95 octane)

at the moment, it's costing me $15 for 1 gallon of toluene... does anyone know where i can get it for less?? i've looked at ace hardware, osh, lowes, home depot... only sherman-williams has it.

i love the better performance, but i think i won't be able to afford $50 for 1/2 tank for long!
 
#2 ·
hey! don't just go out and tell people about this secret! haha.. i've been using 30/70 mix as of a few days ago. btw, use it with low octane gas. i get it for $6/quart around the corner when i want it conveiniently, but $4/gallon with my resources. i can potentially get it for $3.40/gallon with a 55 gallon drum purchase. anything higher than 40/60 and you might want to make a heat shroud from the exhaust manifold to heat the fuel line a bit. at a certain mixture, you need to heat toluene to pre-vaporise it for combustion efficiency.
 
#3 ·
yea dude, i don't plan to go anywhere past 25%... should i just fill up 89 & use more toluene? it seems more expensive that way though, 89 is only about 10 cents/gallon cheaper. haha, everywhere i call to ask if they have toluene... they go "toluene??!?! WTF?!?!? lemme check... NO WE DON'T HAVE IT." bastards.
 
#4 ·
It's great stuff. In the 80's, in Formula 1 racing, it was the primary ingredient in the special "rocket fuel" 114 octane mixture they used.....84% Toluene, 16% stabilant mostly to get decent combustion temps. And they were pulling 1500HP out of a 1.8 litre turbo 4-cylinder engine running (are you sitting down) 73psi of boost in qualifying, and around 55psi durng the race (turned down for longevity).

I used to use it in my track Audi instead of race fuel as it was much cheaper and was great for high-boost turbo cars (mine ran up to 28psi) to avoid detonation.

But it's corrosive to rubber lines and seals, to your lungs when pouring it, and to many other things, so it's not to be fooled around with. And I do not think our cars are able to recognize much beyond 94 octane so its extremely high octane is not worth the trade-off in my opinion (although it's still great stuff).

For my SEL/SEC Euro cars under high-compression, I just use octane booster from Torco (www.torco.com). It's good stuff, not the crap in the auto parts stores, and much safer.

Enjoy!
 
#5 ·
brucemendel said:
For my SEL/SEC Euro cars under high-compression, I just use octane booster from Torco (www.torco.com). It's good stuff, not the crap in the auto parts stores, and much safer.

Enjoy!
Bruce:
Do you mix the torco with regular or premium? Seems if you added it to premium you would go beyond the 94 octane.
 
#6 ·
I've been wondering about that too, but not for the Benz. My '55 De Soto was engineered to run on 110 octane leaded gas, so I typically use a lead additive or Marvel Mystery Oil as a substitute, coupled with octane booster, both added to 93. If toluene can be had a decent price, where? I am paying over $100 per tank for that mixture now, and if I can use 87 with toluene and Marvel for less, I certainly will. Any suggestions?
 
#7 ·
brucemendel said:
It's great stuff. In the 80's, in Formula 1 racing, it was the primary ingredient in the special "rocket fuel" 114 octane mixture they used.....84% Toluene, 16% stabilant mostly to get decent combustion temps. And they were pulling 1500HP out of a 1.8 litre turbo 4-cylinder engine running (are you sitting down) 73psi of boost in qualifying, and around 55psi durng the race (turned down for longevity).

I used to use it in my track Audi instead of race fuel as it was much cheaper and was great for high-boost turbo cars (mine ran up to 28psi) to avoid detonation.

But it's corrosive to rubber lines and seals, to your lungs when pouring it, and to many other things, so it's not to be fooled around with. And I do not think our cars are able to recognize much beyond 94 octane so its extremely high octane is not worth the trade-off in my opinion (although it's still great stuff).

For my SEL/SEC Euro cars under high-compression, I just use octane booster from Torco (www.torco.com). It's good stuff, not the crap in the auto parts stores, and much safer.

Enjoy!
not trying to argue or anything, but the other 16% in the rocket fuel mixture was just 0 octane "filler". that was due to tech regulations. the combustion temps were taken care of by means of fuel heaters. the engines were de-stroked toyota 4AGEs down to 1.5L and wound out to around 11,000rpm. i've actually done a couple swaps with these. the newer formula atlantic motors aren't hard to come buy and are realitively cheap.

also, toluene is not corrosive to the fuel system anymore than gasoline is. gasoline is essentially toluene. no risk. it is pretty nasty stuff to inhale or get on your skin, though.. i completely agree with the overkill factor too. anyone who goes excessivley beyond the reccomended octane rating for the motor is wasting money. but not so much with toluene. it's not just the higher octane your shooting for, but combustion characteristics.
 
#9 ·
not expensive at all by comparison. a typical octane booster with 10 gallons of 91 octane fuel will boost the octane to appx. 91.5. with a quart of toluene mixed with 10 gallons of 91 octane fuel, the octane will be appx 94 octane. so for the same pirce (if not cheaper) of a small bottle of octane boost from the corner store, you can get a whole quart and actually boost the octane. a generic quart of toluene from a random paint place will cost appx $6/ quart. from a larger warehouse, you can get a bigger quantity averaging $4-$5/ quart. in a 55 gallon drum, the price evens out to the current cost of premium pump fuel.

the benefits are dramatic with a high compression euro motor, especially with a more aggresive ignition advance. smooth idle, instant throttle response, and more power all for a few more buck per tank.
 
#11 ·
haha.. i was stating there is no risk in using it in the fuel tank. but if someone is foolish enough to bathe in it, breath it, drink it, or use it as eyedrops then they deserve to go to the emergency room! my safety issue has always been the fact that i'm a smoker. when replacing fuel lines, i always get pissed and frustrated cause i hate it. so i tend to want to go take a break in the shade and smoke a cig. it's always funny when the flame from the lighter spreads down your hand in a quick flash from the fumes burning off! hahaha... i really hope my grassroots safety standards bite me in the ass some day so i learn. :rolleyes:
 
#12 ·
Instead of octance boosters, I used to use a mix of 50-50 regular unleaded (87 octane) and av gas (100 octane low lead) in my '72 TR-6 and my '62 MGA 1600 mkII. Both engines were designed to run on leaded fuel and used to ping pretty bad in the summer. The "low lead" aviation gas still has more lead than the old premium leaded gas used to have. So, mixing 50-50 seemed to work well.
 
#14 ·
NüR-SPEC said:
not trying to argue or anything, but the other 16% in the rocket fuel mixture was just 0 octane "filler". that was due to tech regulations. the combustion temps were taken care of by means of fuel heaters. the engines were de-stroked toyota 4AGEs down to 1.5L and wound out to around 11,000rpm. i've actually done a couple swaps with these. the newer formula atlantic motors aren't hard to come buy and are realitively cheap.

also, toluene is not corrosive to the fuel system anymore than gasoline is. gasoline is essentially toluene. no risk. it is pretty nasty stuff to inhale or get on your skin, though.. i completely agree with the overkill factor too. anyone who goes excessivley beyond the reccomended octane rating for the motor is wasting money. but not so much with toluene. it's not just the higher octane your shooting for, but combustion characteristics.
You're right about fuel heaters and filler. I forgot about that stuff! But were the Honda F1 engines actually destroked Toyotas motors?? Seems like they'd die before doing that.

I believe Toluene is more corrosive to rubber parts than gasoline. I forget why, there's a huge Internet page that expains it all. I will try to find the link.
 
#15 ·
well, if it is more corrosive, i'd love to find out. don't want to go overbored and find out the hard way. but from what i've studied, toluene and gasoline are basiclally the same thing.

as for the formula cars, i don't remeber the specifics of any different engines. but i do know the most common engines were toyota 4AGE motors which are a 1.6L DOHC 16v EFI. as far as i know they used different rods and crank to reduce the stroke for higher rpm aswell as de-stroke it to 1.5L. i have a disc in sotrage with a bunch of photos from my old computer when i lived in alaska. i have some awesome pics of the motors.
 
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