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I had to use regular 87 octane today as every station in and around Buckhead was out of 93. Any short term consequences or would I only have long term repurcussions if I consistently did this?
TripleD
 

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Take it easy on the motor as it will detonate easier, use lower gears when under load and dont excel at WOT. Keep your ear out for a rattling sound coming from the motor, that is preiginition (detonation). The car has knock sensors that will retard the timing to help eliminate it but it can still happen. Use your head and you should be fine.
 

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Get some Toulene from a paint supply store, maybe a local home/hardware store (don't think HD/Lowes sell it, but maybe ACE ?) and dump some in the tank. It is frequently used as an octane booster. Not sure exactly how much you need however.
 

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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.
 

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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.
I never cease to be amazed at the range of experience and talent on this board!
 

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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.
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.
 

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Before Toluene, you might want to stop into a auto parts store and grab a bottle of 104+octane. Just read the label and make sure you get the one without the lead.
 

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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.
 

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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.
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.
Regards,
Jerry
 

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search the board - lots of discussion about octane boosting. Toluene is a good way to go. The cans at the car parts store are positively worthless. It takes way more VOLUME of any known substance with a higher octane level (like Toluene) to make a reasonable difference in your tank, than a 16 oz can, which will increase your octane but about 1/10 of 1%.

As for knocking and dangers of low octane gas, the car's engine computer will detect the knock before you ever hear it, and it will retard the engine timing to cope with it. You will be robbed of power but it shouldn't harm your engine, PROVIDED IT CAN RETARD IT ENOUGH. 87 is pretty low, though, so it may reach a "maximum retard" point before it eliminates the knock. If this happens it will probably light the check engine light, and you should drive with a VERY LIGHT FOOT - and DON'T LUG THE ENGINE - to avoid potential damage.
 

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If you wish to enhance the octane levels in your pump fuel, and are thinking of using additives like Toulene... then make sure you keep the ratio of 4:1 with pump fuel! And out of that 4:1 ratio, make sure you mix toulene with Xylene... otherwise you are gonna end up with corrosion and rubber seal and hose damage!!!!
 

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You guys got me interested to see what is in current over the counter octane boosters and I came across this link. Sorry if its already been posted but it's a good read.

http://www.idavette.net/hib/fuel/
 

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I spoke to my father this afternoon. He owns a gas station...Sunoco for 25 years, Texaco for 8 years and now independant. He said there could be sporadic outages towards the end of the month. A lot of oil companys are perofrming monthly allocations of gasoline. That means they are allowed some % of their normal supply per month...anywhere from 50% to 90%. If your dealer uses up his allocation early on, they will not be getting gas towards the end of the month. So depending on the company and volume of the dealer, you may see outages. This is not mean to be a rumor or start panic or whatever. Take it for what it's worth. It's also more likely that regular (87 octane) would be out before super (93 octane).
 

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I do know that some of the off the shelf items do work(adding about 4or 5 oct).
Toluene, Methonal,Acetone,Xylene, methyl ethyl ketone,butoxethanol and isopropanol. All great cleaners and octane boosters, all in one 16oz can to help 16-20 gallons of 89octane.
I haven't lost an smog equipment in the years of using it.

One great thing about Calif is they have to have a Material Saftey Data Sheet around, this gives you a idea of whats in the can.
 
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