Fuel Management

Hi guys
Read an interesting article on the heady days of 1500bhp F1 engines of the early 80's. Seems like adding Toluene is a quick and easy way to boost octane?

Daniel
1977 450 SEL 6.9
Vancouver, BC

Octane is simply a measurement for preventing for (uncontroled) PRE-ignition ...
Octane has NOTHING to do with HP ....

HP is a product of Torque times revolutions ...
When you double the revolutions you should =if everything is optimized= also get double HP ....

Those F1-motors idled at 8000 RPM and used the range up to 18000 RPM.

M100 motors are limited till around 5300 Rpm MAXIMUM. Those motors are designed for maximum power from idle on i.c. 600 rpm. That is quit a difference with a F1-motor.

The higher the octanenumber the higher the compressionratio of the motor can be without uncontroled pre-ignition. The compressionratio is responsable for the hight of the output of the petrol.

After the emmission regulations in the US the compresionratio was from 9.0:1 reduced to 8.0:1 in the US. [augustus 1969] In other countries the reduction took place end 1972 from 9.0:1 to 8.8:1.

Welknown is that adding ATF also "boost" the octane of the fuel ...

Toluene is a well known octane booster. I recall advertisements many years ago, probably before many readers here were born, certainly before they were old enough to have a strong interest in cars, where the advertisement promoted the addition of Toluene to their petrol as an octane booster; "BP with Toluene" and so on.

One minor correction to Paul's post. The compression ratio in Australian 6.3's was NOT reduced to 8.0:1 in 1969. It remained 9.0:1 until all the pistons in 6.3's were reduced to 8.8:1 at the end of 1972. I have not personally seen an 8.0:1 6.3 piston in Australia and I have seen many M100 motors "torn down" with engine numbers into the 5000's. All had pistons which protruded "above the deck".

Next problem, of course, is buying Toluene. I know it is used in the paint industry, but I have not been able to identify it in a can at the hardware. Every can I have looked at describes the contents and "volatile hydrocarbons" or something similar;Toluene is never mentioned.
Art

Oops..... ,

That is right Art, I had made the mistake that I remembered I noticed the reduction for the US and Australia, BUT that counts for the 6,9 series from the beginning ......

So I mixed up in my memory ... I am getting a little older [:)]

quote:

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Originally posted by daantjie

Hi guys
Read an interesting article on the heady days of 1500bhp F1 engines of the early 80's. Seems like adding Toluene is a quick and easy way to boost octane?

Daniel
1977 450 SEL 6.9
Vancouver, BC

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Absolutely, yes. See this excellent explanation https://en.wikipedia.org/wiki/Octane_rating. Consumer availability varies greatly from region to region, state to state and country to country. Toluene is an aromatic hydrocarbon (similar to benzene) and burns richer than, say, iso-octane, so adding a lot might require mixture adjustments.

Dave

1977 450SEL 6.9, No.923

Here is an interesting article about Toluene, mainly applicable to cars with boost:

https://members.rennlist.com/951_racerx/RocketFuelFAQ.html

Also, we can buy it here off the shelf, though not exactly cheap:

https://www.homedepot.ca/en/home/p.toluene---378-l.1000427944.html




Daniel
1977 450 SEL 6.9
Vancouver, BC

Dan Smith would use Toluene in his fuel when he was drag racing his 6.3, and he certainly had the fastest unmodified 6.3 I've ever seen.

While I was in the pits for the Spa F1 race and when no one was looking, I snapped a pic of the label of an ELF container of rocket fuel - - - speaking of toluene [8D]



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