DougM

No 928 content, but interesting.
<a href="http://www.elektro.com/~audi/audi/toluene.html" target="_blank">http://www.elektro.com/~audi/audi/toluene.html</a>

John Veninger

<a href="http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=14&t=001625" target="_blank">http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=14&t=001625</a>

ViribusUnits

The artical on toluene was a bit hard on methonal.

You can safely mix up to 10% methonal in the gasoline. This sold in some countrys as gasahol(spelling?). It will not dammage your car. The owners mannual say it can be used, but doesn't recomend it.

I would suggest putting the neccery gasoline into your tank before adding the methonal. This away no componet ever gets a straite shot of methonal.

It's not powerful as toluene, but cheaper in some areas, a bit safer, and will still do the job.

The methonal will NOT posion your cat, or O2 sencor. The only problems you might worry about is if you run over 10% methonal, and it reacting with your fuel system. Don't do that.

Rember, it's 10% methonal by mass, NOT volume. Slight diffrence in the amounts.

Old & New

Viribus,

Since when do you care about spelling?

Methanol and toluene enhance the fuel in different ways. Methanol is an oxygenator; a single carbon molecule with an -OH in there. Toluene is a seven carbon chain that has nice burn properties.

CarreraFour

Here is Steve Weiner of Rennsport take on mixing fuel and there are some things you should know as it relates directly to Porsches-

Now is the time to mention the most common octane-enhancing agents present in in pump gasoline, Ethanol and Methyl Tertiary Butyl Ether, otherwise known as MTBE. Both products do a commendable job of increasing octane when used in correct quantities, however each has some drawbacks that you need to know, In some cases, the use of each ingredient is posted on the pump so that you know which one is being used in your area. These blends can change during the fall and winter seasons.

Ethanol is an alcohol that has very clean-burning characteristics. It also absorbs water and will scour out any dirt or impurities present and deposit them downstream into the fuel filter plugging it up very quickly.

The use of Ethanol will require the frequent replacement of fuel filters. In addition you may experience a drop in fuel mileage due to Ethanol's lower energy content. The mixture changes caused by blending Ethanol is somewhat self-compensated by most fuel injection systems, however carbureted cars may require some adjustments or jetting changes to maintain performance.

MTBE, a member of the ether family, does an even better job of octane enhancement and will not create the same fuel system havoc to the same degree that Ethanol can.
The main drawback to MTBE is that it creates major carbon deposits on the valves and fuel injectors. MTBE, being the most widely used fuel additive, requires the constant use of fuel system cleaners to maintain throttle response and power. This is a slow building process and sometimes the performance loss isn't apparent until hesitations, misfires, hard starting and rough iding manifest themselves. Regular use of Chevron' Techron or LubroMoly's Jectron and Ventil Sauber products will prevent these problems. In addition, those Porsche dealers and independent repair facilities that employ the MotorVac fuel system cleaning process, can restore full power and drivability.


<a href="http://www.rennsportsystems.com/2a.html" target="_blank">You can read his entire article "Lets Talk about Porsches- Gasoline, Detonation, Timing" on this topic by clicking on this link.</a> <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

BrianG

Would it be reasonable to say that "Octane Boosting" would be of little value for the pre-S4 928 since they had no knock sensor? This would be assuming that one were already running without knock problems and in "premium" LH-brain mode.

ViribusUnits

I've always cared about spelling, BUT only when it gets in the way of me communicating effectively. Gasahol doesn't like like its right to me, and if you were not reletivly fimiler with the substance, you might assume I spelled it correctly, and that would confuse you. Thus I tryed to spell it as best I could, and made a note that it's probably wrong, to try and avoid confusion. :-)

Ethanol and Methanol are not the exact same thing. Ethanol is a two carbon chain, with an O-H group on one end, while Methonal is a single carbon with an O-H attached. Ethanol is often produced by organtic means. Ethanol is drnking alchaol, sometimes called grain alchaol(spelling?). Methanol is highly toxic, if swallowed. It's commonly produced from methane gas, usualy eighter coal gas, or natral gas. Ethanol is slightly better as bonding with non polar substances. Eighter methanol or ethanol are missible with water. If you have a problem with a bit of water in your fuel system, add a bit of methonal, it'll clear it right up. The methonal will disolve the water into the gasoline. Kinda similer to soap disolveing grease into water. Carried it right on through the engine, and out the exaust. Cool, uh?

I don't see why you'd need to constantly change your fuel filter. If you have a clean tank/fuel lines, there would be no problem. After the inital clean up with ethanol, you shouldn't have a problem. Methonal should have lesser problems than ethanol, because of methanol's lesser affinity for non polar substances.

You'd almost certainly lose a bit of gas milage with methanol or ethanol, BUT methanol should be cheaper per gallon than gasoline, so it evens out, excepting you'd have less range on a tank full.

Oh well, I get I better get out of organtic chemistry before I get hurt. :-) It's just so enjoyable.

Old & New

While we're on the topic, methanol (drygas) is absorbed into the skin quite readily, and competes with hemoglobin for oxygen, leads to blindness & all sorts of nasty stuff.