SLAMMER 2

I JUST HAD ANDY INSTALL A SC KIT WITH NEW INTERCOOLER LAST WEEK. HE SAID HE HAD A BIT OF A TOUGH TIME GETTING THE TIMING SET SO THE ENGINE DIDN'T KNOCK.
I USE ONLY 91 GRADE FUEL. A FEW DAYS LATER
I FOUND I WAS HAVING KNOCKING AT FREEWAY SPEEDS WHEN EXCELERATING. (I HAD TO PUT MY TOP UP TO HEAR IT) I PULLED IN TO AN AUTO PARTS STORE AND BOUGHT SOME OCTANE BOOST AND ADDED IT ALONG WITH A FILL UP. THAT SEEMED TO STOP THE PROBLEM. THE TIMING IS SET BACK ABOUT 12 DEGREES IF I UNDERSTOOD ANDY CORRECTLY.
WHEN I GOT HOME I DID SOME LOOKING INTO OCTANE BOOTS. I FOUND THIS INTERESTING ARTICLE ABOUT TOLUENE. http://www.gnttype.org/techarea/misc...explained.html

HAS ANY BODY HAD THIS PROBLEM AFTER A SC INSTALL?

PowerLabs

Hi,

Try not to use ALL CAPS when you type; it is considered rude because all capitals is used to convey that you are YELLING.

Mine is tuned to take about 19 degrees of timing on 93 octane. I have not heard any knock yet; when Cartek tuned it, they got it to run without any knock by setting a safe rich AFR and pulling timing where necessary, then they enriched the AFR by another 2 points towards redline so that it doesn't knock even on warmer days. It is all in the tune. If you really think it is knocking you should bring it back to Andy and have him check it for you and possibly change the tune to a richer AFR.
As far as Toluene, as your Internet research probably showed you, it was used back in the Formula 1 Turbo days to allow fantastically high (as much as 50PSI+!) levels of boost in those cars, which at the time were making as much as 1500Horsepower from a 1.5Litre 4cylinder engine. It is a reasonably good octane booster but not a very good proposition for a street driven vehicle; your fuel pump, fuel lines, O-rings and miscellaneous fuel delivery components were not designed to deal with high concentrations of Toluene, which is a very effective solvent, and the engine has not been tuned to run it, so you may suffer driveability issues such as sluggish throttle response, difficulty starting when cold, etc. It is also going to get very expensive, very quick. In Michigan it would cost me over $14/gal for toluene from a paint supplier. A much better idea is to tune the car properly so it can run on conventional pump fuel. Another idea would be to install a Methanol injection kit, and a 3rd idea would be to tun a very good octane booster, one containing MMT, such as Torco or similar. Personally if it was my car I'd tune it to run safely on pump gas.

SLAMMER 2

HERE IS ANOTHER ARTICAL SHOWING TESTING OF 10% 20% & 30% TOLUENE MIXES ALONG WITH TWO OTHER TYPES OF OFF THE SHELF OCTANE BOOSTS.
http://www.europeancarweb.com/tech/0...ted/index.html

SEE TABLES AT THE BOTTUM OF ARTICAL FOR COMPAIRISONS

SLAMMER 2

I AM YELLING!!!......just kidding, one of my hard to break habbits. THANKS FOR POINTING MY EXCESS USE OF CAPITALIZATION opps! slipped again...

PowerLabs

As per that ARTICLE (that's how its spelled),

20% Toluene added to 80% 91 octane gas will yield an octane increase of 2 points.

That's about 3 gallons of toluene to a tank. It will cost you an additional $42 every time you fill up, and you will have to carry around 3 gallon bottles of a highly flammable, known carcinogen in your trunk everywhere you go if you think you might need to fill up again. Still think that's a good idea?

For comparison purposes a single 16Oz bottle of MMT based octane booster will result in the same octane level increase for $9.99.

Or (and I KNOW this is coming, so let me address it before someone posts it), you can spend $600 on an Alcohol injection kit, another $400 or so to get it installed, and then $10/gal for every gallon of Methanol you spray on your engine... For the cost of the kit + install you could purchase 100 bottles of octane booster, which would last you 100 tanks, or approximately 30,000 miles of driving. But that's a moot point because the methanol those kits use costs as much as a bottle of octane booster so in reality the kit never pays for itself. AND if you rely on it to provide your engine with enough octane for it to run, not just as a safety net, then WHEN the pump quits, an injector plugs up, the tank runs out or the methanol splashes away from the pickup line during a high speeed maneuver, your engine will detonate and may be destroyed.
That's why I'm not a big fan of meth injection for street cars. THAT SAID, if you want to make big power you will eventually need more and more octane, and then your options become either running the car on race fuel (very expensive) or installing a meth kit. For those applications Methanol injection works well and allows good power increases on pump gas.

SLAMMER 2

Thanks for your suggestions, I may continue to run the octane boost I still have left from my trip back from So. california.

SLAMMER 2

I agreee completely. with a bit more reading toluene dosn't seem like such a good idea.

PowerLabs

Buy the best octane booster you can get and run that. It MUST be MMT based; anything else is junk. NOS Off Road formula is good, TORCO is good, Octanium is good. But you really should have it checked by the tuner because detonation is not normal and a street car tuned to run on pump gas should not require regular additions of octane booster.

Also as another sad little side note, regular usage of octane boosters, specially in quantities greater than specified by the manufacturer, will result in fouling of plugs, Oxygen sensors, catalytic converters, valves, etc... You can always tell engines that run octane boosters all the time because the interior of the combustion chamber is all orange.

SoldSyclone

Xylene or Torco work well too 20% Xylene will get you 96 octane

PowerLabs

Xylene works just like Toluene. It has a slightly higher RON rating but lower specific gravity. 20% Xylene would make 91 octane closer to 94 octane but you would be carrying around 3 gallons of a highly flammable known carcinogen in your trunk and paying about $35 on top of every fill up.

Torco is not even in the same league. First it will cost you $16 per tank, not $35 - $40, and secondly you will get a similar octane increase out of a 16 oz bottle, not 3 gallons. It will have the downsides I mentioned on my last post though, since it is an MMT based booster.