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white79bu
01-27-2005, 05:50 AM
Is anyone driving a high compression motor on the street? I'm running a 12:1 406 sbc. that I have to mix my pump gas with this fuel concentrate I get from Torco. I was wondering what everyone else is doing that's in the same position.

dhardison
01-27-2005, 06:36 AM
My LS7 454 runs 12.5:1 compression and I basically do the same thing as you, mix 92 with 110 Torco pump race gas. I've never tried the concentrate, where do you get it?? How much do you have to mix with a full tank of 92?

When on long trips and I need to refuel with straight 92 I just crank down the timing to 4 degrees or so. It obviously KILLS performance, but for highway cruising it keeps detonation at bay.

Dan

ProdigyCustoms
01-27-2005, 07:05 AM
I have friends running 14:1 on race gas, and cruising a lot. The hot set up is sdaid to be water injection for a motor like yours just over the edge. A lot can be done with cam timing to lower cranking compression, timing and timing curve to bring the advance in slower and limit the total advance.
The later I have had to do a lot on factory COPO, LS6, ZL1, Z28, cars that were born with 11-12:1 compression, and were now even a tick higher after a couple passes on the heads to clean the edges. I have got some really good results limiting timing and curve and being able to run pump gas and no additives, but as our friend Dan says, it does hurt performance, it robed 3/10ths from a LS6 car we did a before and after test on.
We have a what is now 12:1 L88 (after milling heads and decking the motor), that runs fine on pump gas. Just put a bit to big of a stick in it to bleed cranking compression.
We are going to be trying a brand new water injection on 2 projects, a Procharged 496 motor trying to run 1200HP on pump gas, and also on my street racer for a big NOS shot using pump gas. We are hoping for big things, we will let you know.

camcojb
01-27-2005, 08:17 AM
My LS7 454 runs 12.5:1 compression and I basically do the same thing as you, mix 92 with 110 Torco pump race gas. I've never tried the concentrate, where do you get it?? How much do you have to mix with a full tank of 92?



Dan

You can get the concentrate here:

Torco Race Fuels (http://www.torcoracefuels.com/)

Make sure you use the leaded version if you don't have O2's; it is MUCH more effective than the unleaded version, although their site says they have the same increase in octane. One quart of the leaded race concentrate in 20 gallons is supposed to raise octane 5.5 full points, not tenths. Two quarts will get you 11 full points according to them. The unleaded stuff in the same range is only worth 1.5 points (max of 3 points with two cans) according to their product developer.

Jody

dhardison
01-27-2005, 08:37 AM
Thanks Jody! I've been looking for quite some time for an easy/safe way to increase my octane when on long trips and subject to 92-octane pump gas. Up to this point I've been carrying a couple 5-gallon gas jugs with 114 race gas and mixing at each stop. Not reeeeeal safe! The 32-ounce cans will be MUCH more convienent.

Dan

camcojb
01-27-2005, 08:41 AM
It's about half price if you buy it in the 5 gallon can instead of by the case. You might try it first, then switch to the larger volumes, the price drops a fair amount. Gets to about $9.50 per tank of gas.

dhardison
01-27-2005, 08:43 AM
Yeah, I was doing the math on that as well. I think I'll pick up one case of 32oz bottles and give it a try. Then I can reuse those bottles when I place the order for the 5 gallon cans.

Thanks again,
Dan

ProdigyCustoms
01-27-2005, 09:13 AM
One thing to be careful of with octane boosters, that may or may not be an issue with this Torco. We used to use lots of 104 real lead when we were heavy in muscle cars, but had big problems with stale gas in no time flat. In a few months, the gas would be varnish like fuel without additive would be in a few years. Since some cars could sit on the showroom for months on end, we had to be carefull to only use as much fuel as we may need to run them.
We killed some fuel systems before we figured it out.

dhardison
01-27-2005, 12:12 PM
I wonder if fuel stabilizer would help cure the varnishing problem?

Dan

white79bu
01-27-2005, 12:33 PM
I talked to someone at Torco a couple of months ago about the consentrate going bad when setting. He told not to worry about it because it would't break down. But he said if it made me feel better I could put fuel stabilizer in and it wouldn't hurt it. Also if you want to buy a case of the cans try getting it at www.need4speedpower.com (http://www.need4speedpower.com) it seems to be cheaper than going through Torco. It work great for me I just keep the case in the trunk of the car. I mix it with 1 can to a tank of fuel but I am thinking about mixing it with 1/2 can to a tank. The leaded version is some strong stuff. Andy

pro68/540
02-02-2005, 05:06 AM
Wouldn't water injection have the same effect as alchol/meth. Leaving water in your pan, making your oil grey? (im not saying you have a waterhose in your pan :) )

camcojb
02-02-2005, 07:09 AM
Wouldn't water injection have the same effect as alchol/meth. Leaving water in your pan, making your oil grey? (im not saying you have a waterhose in your pan :) )


The water/alcohol injection systems inject with high pressure so it's a mist, not drops of water. The heat in the combustion chamber absorbs all the water, there'll be no residue at that point. If you were injecting enough water to contaminate the oil, you'd be misfiring very bad as water does not burn.

Jody

myclone
02-02-2005, 07:26 AM
One thing to be careful of with octane boosters, that may or may not be an issue with this Torco. We used to use lots of 104 real lead when we were heavy in muscle cars, but had big problems with stale gas in no time flat.

What kind of difference did you see as far as detonation when using the 104? Ive performed some datalogging tests on the 104 stuff (not the leaded stuff though) and it didnt improve knock retard counts at all on my syclone when ran with 93 pump gas at 17psi of boost. I verified it was true detonation by pulling the plugs also (FWIW).

You can make your own "octane booster" if you want by adding xylene to regular unleaded. IIRC a 3 to 1 mix of 93/xylene equals 100 octane and it wont harm the O2 sensor and you can get it fairly cheaply at a paint store like sherwin williams in 5 gallon cans. You can get smaller quantities too but the price goes up accordingly.

Before alchy/water injection the turbo guys were using xylene on a regular basis not to mention no one can tell your running it by the smell of the exh like you can race gas :naughty: .

camcojb
02-02-2005, 07:30 AM
Xylene works great. Unfortunately here in California it is anything but cheap. In the last year it has risen from about $5. per gallon to $10 to $12 per gallon depending on where you go!

Jody

myclone
02-02-2005, 07:41 AM
Xylene works great. Unfortunately here in California it is anything but cheap. In the last year it has risen from about $5. per gallon to $10 to $12 per gallon depending on where you go!

Jody

~$12 a gallon? OUCH!!! Sorry, Californias HAZMAT issues didnt cross my mind since Im on the other coast but I guess the cost would be a problem if you live in a state with stringent standards on chemicals.

And I thought all this time it was the recent poplularity of turbos that had made alchy injection all the rage.