100 Octane in a '94 9000 CSE

Hi all,

I have a '94 9kCSE. I normally run Chevron or Unocal premium in it (91 Octane here in So. Cal) with good results.

One of the stations here is selling a 100 Octane that they call racing Fuel. I'm wondering if it would cause any damage if I ran it in my 9k, or if it is just a waste of money. I would not use it all the time, but maybe a tank every three months.

What about my '02 Viggen, would it benefit from running a tank in it every once in awhile?

TIA

Craig

Reply to
Craig M. Bobchin
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Some stations in the midwest were at one time selling leaded fuel, calling it "racing fuel" (off road use only). Might want to make sure that isn't what you are looking at. ;-)

If you want to use it, reset and calibrate your system to take advantage of it. Otherwise it's not as beneficial as it could be.

Reply to
joe schmoe

Craig M. Bobchin wrote in news: snipped-for-privacy@news.la.sbcglobal.net:

Depends on what kind of racing they are selling it for. If it's for folks running at the local dirt or asphalt track, no. It's leaded and meant for cars with carbs. Find out what race track is near there. That's where their customers come from. If it's a drag strip, it could be unleaded but it also may have alcohol added to it (alky). It could also be aviation fuel and have additives in it that would cause problems with fuel injection systems. Ask at the station before putting any in your car. There's no real advantage to it and it could cause a lot of harm.

Reply to
Laura K

Yes. That aviation fuel is called LL100 ( low lead ) although actually the 'low' is something of a misnomer. It was simply low by 'old' standards.

Using that is death for your cat.

Graham

Reply to
Pooh Bear

Actually, it's not whether you have a carb or fuel injection that matters, but whether you have a catalytic converter, of which race cars do not.

Reply to
Malt_Hound

At least in the US, there is an unleaded 100 octane gasoline sold in far flung outlets, and if my memory is correct, it is/was called Cam2. I ran a full tank in my '88 9k turbo, and the pressure needle would pin into the red - but the car did not seem to perform all that much better, nor was the additional mileage enough to justify the extra cost (back in '88, I seem to recall >$2.00 a gallon price).

I tried to find some more once when having trouble getting through emissions testing, but then could only find the leaded variety.

One other thing - again if my memory is correct - the original 9k engine was marketed as being able to run on any fuel, the only limitation being the cat.

Another note: I have an old R60/6 bike that BMW specified us>Laura K wrote:

Reply to
cs

Octane rating is an expression of stable fuel combustion not energy or power.

Reply to
darthpup

"Craig M. Bobchin" skrev i en meddelelse news: snipped-for-privacy@news.la.sbcglobal.net...

"Fire away". You can use the 100 Octane in both your Saab's and they'll both benefit form it, in gettting more Hp and Nm.

Cheers!

Reply to
Henrik B.

Just to clarify, gentlemen, high octane "pump" gasoline is not true "racing fuel" if it is being legally sold for street use. True racing fuel has lots of nifty, rather unpleasant additives to allow it to actually package more potential BTU's of energy/unit of volume. Think benzene, toluene and nitro methane to name a few. These brews are tightly regulated by the various racing sanctioning bodies and the EPA. All pump gas, regardless of it's octane rating, has identical (with in a small error percentage) energy (BTU) potential. The benefit of higher octane fuel is limited to your engine's tendency to "detonate" under heavy load. Some engines, notably those with high (>9/1) compression or loaded-up combustion chambers, will cause the fuel charge to burn at such a fast rate that the entire release of energy occurs when the piston is only slightly past TDC. The connecting rod has a very poor force angle on the crank at this point and this unproductive explosion is heard as a "knock". Lots of noise but not much torque. The additive package in higher octane fuels slows down the burn so that the charge is still expanding as the crank reaches 90 degrees ATDC. Max torque. Same BTUs. SAABs benefit from higher octane for two reasons. First, most non-turbo models qualify as "high compression" engines and, although not "hc" by spec, the turbos become "hc" under load. That's the function of the turbo; jamb in more air then nature alone can do. Second (the tricky part) ever since SAAB developed the Lambda system all Saabs are in a constant state of "retuning" themselves. The engine is setup to have ignition timing that would be so "advanced" that the car would eventually self-district if not for a system that continuously monitors the behavior of the burn cycle and "retards" the timing just enough to keep the knocks away. Feed it cheap gas and it will run fine but with limited power due to the retarded timing. Feed it 93 octane and the timing is allowed to advance to take full advantage of the slow burning charge. To take advantage of 100 octane fuel you must change the engine management "mapping" to allow higher boost and more radical timing advance. While you're at it, port the heads, install bigger, lighter valves, get a bigger throttle body and air mass meter and get a decent header set. And keep a spare transmission handy.

Woof

"Henrik B." wrote in message news:43a8ae2b$0$8785$ snipped-for-privacy@dread14.news.tele.dk...

Reply to
WOOFER

"WOOFER" skrev i en meddelelse news:LzJsf.56233$ snipped-for-privacy@twister.nyroc.rr.com...

Correction: Ever since Saab introduced the Trionic system. ;o) Lambda has to do with the Catalytic Converter.

Cheers!

Reply to
Henrik B.

No it has not... The lambda sensor measures the unburnt fuel (hydrocarbons) in the exhaust fumes

- lean or rich, and signals to the fuel injection ECU to inject more or less fuel. The cc. just burns any hydrocarbons present in the exhaust, regardles of the lambda sensor, to lower exhaust emisions of HCs .

Reply to
MH

You're right of course. Thank you! It's been a few years.....

Woof

Reply to
WOOFER

K-jetronic went out because Lambda came in as I recall. Not enough control parameters with the mechanical injection system. Too bad... it was the last system I truly understood.

Woof

Reply to
WOOFER

"MH" skrev i en meddelelse news:dp71pu$45b$ snipped-for-privacy@news4.zwoll.ov.home.nl...

....for the Catalytic Converter to function correctly. ;o)

Reply to
Henrik B.

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