Octane Boosting

[Natchamp]

I have been doing a little research regarding octane boosting and what type of fuel I will run in the Beast. I came across a couple of articles I thought were interesting.

http://home.kscable.com/ssutton/miata/engine/toluene.html

I sounds like it makes a lot of sense, has anyone tried this?



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Mark
The Beast
mark@hargett.com

[Greg-slant/cab]

Mark,
I have been keepin an eye on your site and the progress of the car. Last I read you were trying a new pulley/belt system. What is the latest update? Is she tearing up the roads yet?

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Greg-slant/cab
http://www.geocities.com/gregslantcab/

[Bill Verburg]

You might want to take a peek at the following link
http://www.faqs.org/faqs/autos/gasoline-faq/part1/

[island911]

Thanks for the link, Bill.

My favorite part was at about 90% thru when the tecno talk gets broken with;
"9.5 Why are hydrogen-powered cars not available?
The Hindenburg.
The technology to operate IC engines on hydrogen has been investigated in
depth since before the turn of the century.. . ." LOL

Really thorough info. You should post this link for any of the fuel related questions that arise here.

---

'81 Platinum Metalic SC COUPE

[This message has been edited by island911 (edited 07-04-2001).]

[RarlyL8]

Toluene is no secret brew. I plan to run close to 100% toluene if and when I take the turbo motor out for some serious fun.
Where I work we buy it by the 30,000 gal truckload. Pretty cheap for me!
Problem with it and the gas companies is that the EPA has it on their VOC hit list. In the chemical industry this is not a problem as long as you show 100% recovery in your processes (like we do).

[Natchamp]

Bill, interesting reading (when I wasn't falling asleep . I didn't see anything in the article that refutes what my link points out and what is possible by using Tolulene in the proper manner. Did I miss something?

Greg, I'm still waiting on my pulleys. I can't wait to get the thing back on the road. While she's on the rack I'm doing some other stuff like installing a intercooler fan and water injection for the intercooler (to cool the intercooler/air, not in the intake charge itself). I will control/program both the fan and the water with my Haltech. I'm also installing a exhaust temp gauge and another boost gauge for b4 the intercooler. I also purchased a wide band O2 sensor system. It's like the $3500 Motec system but for much less. I found they have it in Sweden and Austrailia. It comes with its own ecu and is 0-5 volts. I will use it to map and program my Haltech. It's extreemly accurate, has no lag and is real time (not like the normal 0-1 volt sensors). When I tune my car I will be able to know exactlt what's going on and be able to adjust both the ignition and injection. The Haltech also does a datalog where it records a bunch of engine parameters (air temp, boost, O2 ratio, etc.) every 1/10th of a second. So I can go for a ride, put it under load, come back and download the data and analyze my settings. I'll keep the board posted.

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Mark
The Beast
mark@hargett.com

[Bill Verburg]

I don't use it myself but its been a common prctice, for years, for use on turbo Audis to mix common paint store toluene and or xylene with gasoline in the ratio ~1 or 2:20. results have been reported to be excellent with no reported problems.

[Roland Kunz]

Hello

The Tulohol story was allready covered somewhere else...

I still beleive in Moth Balls Myhts.

At least it keeps the spider webs out off the fueltank.

Grüsse

[RarlyL8]

Mothballs are no myth. Naphthalene has a higher octane rating than toluene.
The problem is you need to do the math and know your fuel system and engine before using these materials.
Tolene will attack neoprene rubber fuel lines and fittings just as methanol will. Too much toluene (octane) and you burn valves. Octane and boost levels must match up to minimize combustion temperatures. Ignition timing must also be done correctly. If you aren't sure what your valves and fuel system are made of or you don't want to do the math then stay away from additives.
The author of the toluene article showed some respect for the situation by starting out with a low ratio mixture and working up. Use a target octane rating and calculate how much toluene you need to get there.
Also, I stated previously that I would use close to 100% toluene when hotrodding the turbo. This is the purity of the toluene. The blend with gasoline would be more like 1:15 or less, depending on the gasoline used. The stuff you get at the furniture stripping store most certainly is not 100%.
At any rate, I would not use these types of additives too often in a street car. Aromatic and saturated hydrocarbons do not burn clean. This will carbon up your motor over time. They also burn hot and usually attack rubber.

[Natchamp]

rarly, arn't you going to use some type of lubricant like marvel or something? I also read the moth balls are not a myth but they are not always made out of Naphthalene these days so I figured Toluene would be the best solution. With my Haltech and my gauges I will be able to address the tuning and monitoring issues. What I'm trying to figure out is should I tune my motor with the mix or without the mix and what I can do to address the deposit issue. Any ideas?

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Mark
The Beast
mark@hargett.com

[RarlyL8]

Mark - are you planning to use toluene as an octane booster all of the time? If so then this is only the begining. My comments so far have been only to address the issue of toluene as an octane enhancer. Actually doing it can be rather complicated. I plan to use it very sparingly (don't have an engine manegement system) which uncomplicates things.
With your Haltech can't you set up a special fuel/timing curve just for higher octane? Do you have head temp sensing capability? Are your fuel lines steel? The 930 system is not all steel.
How much lubricant or other additives you need will depend on how often and how much octane you run. I have no experience with boosted street engines running high octane all the time. I ran turbo blue in my street machine only on race day, no problems.
Naphthalene has too high an octane rating, in my opinion, to be used on a regular basis. Purity is an issue. I have made fuels in the lab with pure chemicals, nothing over the counter.
Boosted small ci racecars can get away with running a lot of toluene or alcohol because they can also run 45lb of boost! You can run extreme octane in an extreme environment. I'm a conservative chicken when it comes to street cars. I'd rather use it as an insurance policy against detonation than to HAVE to use it due to overboosting. Do you anticipate a problem with detonation or are you wanting to turn up the wick a little?

[Natchamp]

Yes

I want to use it as an insurance factor for detonation and I want to be able to turn the wick up if I so desire. With the Haltech I can do anything (put it like that). I can have as manny maps as I wish but I'm thinking I'll prabably have 2, 1 for normal and 1 for "violence". All my fuel lines are stainless steel and aeroquip lines with AN fittings. I am not planning on pushing the limit, only as a good enhancer. Because of the infinate tuneability of the Haltech, twin plugs, wide band O2 for tuning, exhaust temp gauge, etc. I should be pretty safe but I do have a lot of money tied up here and more work than you can imagine. Maybe if I just add the minimum to a tank of gas and tune against that for normal and then have a more aggressive ratio for the more agressive map.


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Mark
The Beast
mark@hargett.com

[RarlyL8]

This may sound over the top, but have you considered a dedicated fuel system with extra injectors (2-stage) for use when "turning up the wick"?
That would be an optimum and prudent safety arrangement for part time use on demand.
The same type of setup when using nitrous. I came close to buying one of these last summer, been kicking myself every sense.

I know you've got a ton of work in your car and motor. With the versatility of the Haltech you may not need extra injectors, the problem is being certain that the fuel shot in at high boost is correct and not diluted by what was previously in the tank.
I forget the rating on your injectors, do you anticipate going over an 80% duty cycle?

[MMBRAZIL]

Why not use aviation gasoline they are 100+ octaine?

Another question I was using 87 octane on my 74 CIS and had pinging when at 4k plus....I changed to 92 and now its ok...wasnt my car supposed to work with 87?

[BlueSkyJaunte]

Avgas is typically leaded -- curiosity didn't kill the cat, lead did.

[RarlyL8]

I think cost is the issue. Adding toluene to up the octane a little will only cost pennies per gallon.

Detonation can be caused by many things such as timing, ambient air temperature, elevation, age/condition of your engine, etc.
You can back off the timing a tad or use higher octane fuel. My '78SC runs on 87 octane gas. No problems, but the temps when I drive the car hard are never over 90 or so.

[Natchamp]

Avgas is leaded so I really don't want to use that. Race gas is expensive and a pain in the but to do because I would need to get a 55 gallon drum and always need to mix about 1/2 a tank. The toluene solution sounds good because it's cheap and I would only need to add a little. I could even store a gallon container in front so when I need to fuel up I would always have my "stash".

Rarly, I reasearched the staged injection and certainly my Haltech can do that with no problem. Since I am only shooting for 375-400 little horsies I don't think I need it. The problem is not getting enough fuel at high boost. I have 440cc injectors and they calibrate out to a little over 400hp. They are not soooo big where I will have idle problems because of the minimal duty cycle required at idle. I just want the higher octane for insurance against detonation and a higher octane will also make it run better and crisper. I think the key for me here will be to not go over board on the ratio of it. Have you ever downloaded the software for the Haltech? You should do that and you can see how versital it is and how you can program it to do whatever you want. You can download it at www.haltech.com.au
cheers.

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Mark
The Beast
mark@hargett.com

[Roland Kunz]

Hello

The best solution would be to mix the fuel with the tulohl inside the car depending on the actual required octane needs. Just look at the NOx systems. Normaly a throttle switch under full load will work but better would be to integrate it in the injection map with nock sensor.

Some rubbers do withstand tulohol and benzol.

PVC or styrol will have problems. The teclamit CIS fuellines will have problems with the pure stuff so a complete seperate feed line makes sense. On the Motronic the fuellines are steel.

The rubber fuelhoses from Porsche are mostly from Continental and withstand benzol for a limitet time. They will age and get hard.

Grüsse

[lsolon]

I haven't gotten through your site entirely, and this doesn't pertain to octain but are you running water inj. in that beast? I'm sure you could build your own or go to aquamists site.

[Natchamp]

Isolon, the water injection is not going in the intake charge, its only a fogger/mister for the intercooler/fan to help dissapate the heat from the intercooler and decrease the intake temp.

Roland, interesting point. I could actually put a 7th injector strategically placed and control it with my Haltech to come on at a desired boost, etc. I think I'll just try mixing it in with the gas at first. Putting another injector on would require some extensive work.

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Mark
The Beast
mark@hargett.com