Coleman Fuel Question?

[RonShaw]

Rick,

I understand. That's why I asked above for clarification if the ruling for LSG pump gas was only when records are involved. BTW, that is the latest records form.

 

[Andy Brown]

I set an IMPBA record using Coleman this year and I listed "Coleman" as the fuel. It's in the record book that way.

I ran it back to back in the QD 30.5 cc and there was zero difference in speed compared to 87 pump gas. I did have have to lean the needle a tad for the Coleman.

I switched from the pump gas to the Coleman because the pump gas gave me headaches.

 

[Doug Smock]

I'll fix the application......................................

 

[RonShaw]

Andy,

I had a lengthy conversation with John Finch about the same topic. He swears by 87 pump gas, ethenol, stabil, and castor. He did extensive testing and did not find any advantages over his brew above compared to several high octane types of fuel.

 

[RonShaw]

I'll fix the application......................................

Thanks Doug. That clears it up for me....

 

[JimZaremski]

Andy,

I had a lengthy conversation with John Finch about the same topic. He swears by 87 pump gas, ethenol, stabil, and castor. He did extensive testing and did not find any advantages over his brew above compared to several high octane types of fuel.

FWIW the Zenoah manual says they recommend 90 octane, but I wasn't sure what method and e-mailed them about the rating. Turns out they mean 90 RON (which is the number used in Europe and elsewhere) which would be ~ 85-86 octane here since we use AKI (R+M)/2.

 

[anthony scardina]

I remember hearing that Coleman fuel actually produces sloghtly LESS power than pump gas and the reason it is so widely used is because it lasts longer and will not gum up carburetors and varnish up pistons, leaving the engine looking brand new when it is rebuild time.

I worked in a small engine shop for a couple of years and the absolute number one problem in an engine that wouldn't run? You got it, a gummed up carburetor. I tell everyone to use gas within a month or two then pitch it, regardless of "stabilizers."

One shop I worked at even sold pre mixed white gas for use in seldom used equipment such as string trimmers and chainsaws.

 

[Grimracer]

[SIZE=medium]This post does not deal with the legality of White gas...[/SIZE]

[SIZE=medium]Something to consider,[/SIZE]

[SIZE=medium]White gas is 70 octane.. (I know, I know.. what the heck good is that!... that’s no good!).. or is it?..[/SIZE]

[SIZE=medium]With a typical 2 stroke gas engine I have found having the flame propagation stop by the time the piston exposes the exhaust port the real benefit to white gas. The flame does not heat saturate the pipe (or muffler) providing much cooler runs as well as consistent runs.[/SIZE]

[SIZE=medium]Remember high octane equals long flame duration.. its just that simple.. on a 4 stroke valve engine this is great. Not so much on a small displacement 2 stroke however.[/SIZE]

[SIZE=medium]O well.. most will poo poo the facts.. [/SIZE]

[SIZE=medium]Better yet.. get out and test it yourself.. put a temp sensor on the exhaust and RPM sensor on the flywheel. Measure some lap times. The consistency of the run will likely surprise you.[/SIZE]

[SIZE=medium]Grim[/SIZE]

 

[JimZaremski]

"octane" number is a rating of the fuel's resistance to autoignition. nothing more.

 

[Grimracer]

The higher the octane the slower the burn....

Grim

 

[JimZaremski]

The higher the octane the slower the burn....

Grim

http://www.whitfieldoil.com/www/docs/171.284/vp-racing-fuel-

"The octane number of a gasoline has little to do with how fast it burns or how much power the engine will make. Octane number is the resistance to detonation. If the octane number is high enough to prevent detonation, there is no need to use a higher octane gasoline since the engine will not make any additional power. Octane number is not related to flame (burn) speed either. "

 

[Grimracer]

OK.......

Grim