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Discussion Starter · #1 ·
i had this crazy idea yesterday when i was in the grocery store.

what if i decided to add one or two 16oz bottles of isopropyl alcohol to a tank of 91 octane gas ?

if my calculations are correct, that should be good for about one octane point per bottle.

any negative effects or reasons why i should not try this ?

got my flamesuit on, awaiting your feedback ;)


J.
 

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well it would increase octane rating, but would decrease the energy potential of the fuel (alcohol has a lower rating). So basically you can run more timing but per every volume of mixture you inject but your injecting less energy as you would have with straight gasoline. The difference between blended fuels and straight fuels is of course the alcohol/ethanol but when your talking about 100 octane gasoline and 91 octane gasoline, the hydrocarbon chains are broken down and more refined in 100 than in 91 or 93, meaning the energy is more accessible and consistent under certain conditions (increased timing). Alcohol should only be used as means to tune within a safe parameter when race fuel is not present, i.e. pump and alcohol injection
 

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Discussion Starter · #3 ·
dannyc1225 said:
well it would increase octane rating, but would decrease the energy potential of the fuel (alcohol has a lower rating). So basically you can run more timing but per every volume of mixture you inject but your injecting less energy as you would have with straight gasoline. The difference between blended fuels and straight fuels is of course the alcohol/ethanol but when your talking about 100 octane gasoline and 91 octane gasoline, the hydrocarbon chains are broken down and more refined in 100 than in 91 or 93, meaning the energy is more accessible and consistent under certain conditions (increased timing). Alcohol should only be used as means to tune within a safe parameter when race fuel is not present, i.e. pump and alcohol injection
thanks. that was quite helpful! didn't know about the energy levels.
so, basically, it's not worth the effort ?


J.
 

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superhero06 said:
Try some toluline! It really kicks ass. Buy it at any paint store.
From what I've been reading, it seams Torco is a better option:
http://forums.nasioc.com/forums/showthread.php?t=994149
sponaugle said:
Torco, and the NOS Race octane boost both use high levels of MMT, which can raise octane much higher then the equivelent ratio of toluene or Xylene. MMT has an effect similiar to lead in that small quanties can raise the measure octane by a significant amount.

The NOS Race formula ( not legal for street use ) has about half the MMT of Torco, and is about $10/can. Torco us $14/can, but the can is twice as big.

I have ran extensive amounts of Toluene in my car, and it can be very effective, but requires not only 3-4 gallons of Toluene per tank, but a suprisingly different tune. The stoich ratio of Toluene is a bit different the pump fuel.

I have now switched entirly to Torco from Toluene.

Jeff Sponaugle
PDXTuning.com
and
http://forums.nasioc.com/forums/showthread.php?t=420798
 

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jph said:
thanks. that was quite helpful! didn't know about the energy levels.
so, basically, it's not worth the effort ?


J.

well.. basically in a stock engine its not worth the effort. If you were running a 20g on pump with a 22 psi tune then yeah it would be worth it

if your serious about raising octane then just mix in some race gas, it smells good too, :D

but if your going for the safety margin then just pick up an alcohol injection kit and run off the shelf rubbing alcohol its 91% isopropyl and 9% straight water... then you can get a pump gas tune and an aggressive alcohol injection tune

i wouldn't run additives for gasoline because its just going to lower the BTU rating for the fuel. Sure it will increase the octane rating but injection is a far better method because you can inject it only when above say 10 or 15 psi to reduce knock tendency, at that temperatures it will improve theoretical compressor efficiency also and cool the intake charge, rather than simply raising octane...

on a side note for the price of 100 octane fuel at 5 bucks or so a gallon, at least thats what is around here, you can go with a lightly oxygenated fuel like VP street blaze 103 or something and mix it in quarters in the tank... with that you'll be able to tune more aggressively, tune for a safe threshold, and it will provide more energy per volume due to it being oxygenated
 

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Discussion Starter · #7 ·
thanks for al the info guys!

i knew about torco and NOS octane boosters, but well... i was hoping to throw in something cheap and easy to get to in my local grocery store, for when the temps hit tripple digits again (like today) and i'm stuck with 91 octane gas; just for peace of mind (an added octane pint or two).

i'm not looking to gain any extra power or agressive tune from it.
i can't get race gas locally (that i'm aware of)
and i don't want to go the injection route.


J.
 

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jph said:
thanks for al the info guys!

i knew about torco and NOS octane boosters, but well... i was hoping to throw in something cheap and easy to get to in my local grocery store, for when the temps hit tripple digits again (like today) and i'm stuck with 91 octane gas; just for peace of mind (an added octane pint or two).

i'm not looking to gain any extra power or agressive tune from it.
i can't get race gas locally (that i'm aware of)
and i don't want to go the injection route.


J.

well.. you can order race gas, im sure gruppe-s has some up there... i just noticed your from san jose .. im going to be a freshman at santa clara this fall, i was up there a month ago and damn it was like 100 degrees, its just starting to cool down a little from the triple digits in socal. I know what you mean by that 91 octane gas, it sucks my i/c sprayer light came on at 3500 rpms today :eek: almost felt like a honda civic
 

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I believe there is one by big dog's grill.

jph said:
thanks for al the info guys!

i knew about torco and NOS octane boosters, but well... i was hoping to throw in something cheap and easy to get to in my local grocery store, for when the temps hit tripple digits again (like today) and i'm stuck with 91 octane gas; just for peace of mind (an added octane pint or two).

i'm not looking to gain any extra power or agressive tune from it.
i can't get race gas locally (that i'm aware of)
and i don't want to go the injection route.


J.
 
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