Can't say I know of anyone who has used Toluene in their M5, but I know tons of guys who have put it in their Audi (1.8T and 2.7TT primarily) with no ill effects.scriba said:I just bought my '03 M5 last week and as a result haven't had an opportunity to add anything to this board yet (ie: I'm a Newbie). I have been a refinery process engineer for 23 years and would caution you adding anything to an expensive M5's tank to boost octane. The octane shortage will probably be over by the time you need to fill your tank again.
Octane blends linearly (1/2 gal of 99 plus 1/2 gal of 101 will give one gal at 100 octane). Toluene has an (R+M)/2 of 106 octane BUT is has a vapor pressure of 0.5 psi (doesn't ignite very easy compared to other gasoline components) so by the time you get your desired octane (if you could get it to mix) the car may not start or run very well.
Hope this helps.
Interesting. The Audi guys report good success with a 1:10 ratio of toluene to gasoline on their turbo cars. As you say, it can't hurt, and it may help. Sherwin Williams reportedly carries it, at least they did at one time.scriba said:Don’t get me wrong; toluene (and other aromatics like benzene) are components that are great octane enhancers when blended correctly with other components. If it weren’t for government regulations, and the fact that toluene and benzene are (or at least were) more valuable as a chemical feed stock than gasoline, there would be higher concentrations of these components in the current gasoline pool.
What I am flagging is that it will take about 5-1/2 gallons of toluene added to 12 gallons of regular to get to the octane of premium gasoline. That’s a lot of low RVP material to add to the tank even at a low elevation like Atlanta.
Folks adding a bottle or two of toluene or benzene to the tank won’t hurt their engines but they probably aren’t getting the performance enhancements they think they are getting. Realize this is the engineer talking, when I was drag racing in the ‘70’s/early 80’s ,when the government was phasing out lead, I was doing the same thing.
Welcome to the board!scriba said:I have been a refinery process engineer for 23 years...