Picked up a bad batch of fuel the other day causing some pinging in Old Red. Diconnected the vac adv for a temp fix, and then went to the local airstrip and put 5 gals of 100LL in the tank. so what's that 5/18 = around 30% mix.

Sure no pinging, but no rip either. Wish I had a ET slip to prove it rather than seat-o-pants. Only other change was a fresh set of ACFR3LS plugs.

Again, run the minimum octane level required , else you'll lose power.

Daves70 was with me and he noticed it too. Motor actually 'hiccuped' once. never does that. ( Dave - don't tell about the 'inspection' we got from the local fuzz !)

No longer a believer in $3.35/gal 100LL. I'm going to find some toluene for that occasional bad batch of fuel.

Oh, and 8.6 DCR with alum heads is MAX with 93, at least in this ride. Right on the cusp.

Just an FYI.

I`ve tried it a few times for the track.
Once the 100LL made its way to the carb there was a noticable difference.
The idle rpms would drop some and the motor felt lazy or "mushy" if that makes sense.
Took more pedal to move up in the staging lanes also.
Never tried it again, the car ran better/quicker on 93 Amoco

Interesting. While no ET as I said, same effect. Idled smoother/quieter ( not in " Hg, just in sound), but I thought it was the new plugs, old ones had been in for around 4500 miles.

I work for an air survey company and the mechs in the hanger run AvGas in the 6cyl powered tug. It absolutely kills the thing, to the point that it will barely run. There is something in the formulation that is specific to engines running at a constant rpm ( usually around 3000 ) for extended periods at low atmospheric pressure and temperature. I don't think you can fairly compare it to race gas, based solely on octane numbers.

Sounds like it's good for the 10.5 hour pulls at 3350rpms I do to Nashvile is all. At 3.35!/gal. Or this guys stuff is so full of stabilizers, it's cut. Anyway. No more. For now, it'll stop the pinging and as the mix drops back by adding fresh 93, it'll get its rip back. Pinging is awful, btw. need about 4cc in those chambers!

The old Green stuff ran great in cars, but I too remember when that went away and I tried the 100 low lead (blue) and the car was a stone.
With todays gas prices.....race fuel isn't looking all that bad!
HA!
Here in Oregon, about $2.50/gal for premium. And it's up to the buyer to determine if it's oxygenated or not. Some stations run that crap all year round, others only in the winter when the County tells them they have to.
Ron

Originally posted by 427L88:
Picked up a bad batch of fuel the other day causing some pinging in Old Red. Diconnected the vac adv for a temp fix, and then went to the local airstrip and put 5 gals of 100LL in the tank. so what's that 5/18 = around 30% mix.

Sure no pinging, but no rip either. Wish I had a ET slip to prove it rather than seat-o-pants. Only other change was a fresh set of ACFR3LS plugs.

Again, run the minimum octane level required , else you'll lose power.

Daves70 was with me and he noticed it too. Motor actually 'hiccuped' once. never does that. ( Dave - don't tell about the 'inspection' we got from the local fuzz !)

No longer a believer in $3.35/gal 100LL. I'm going to find some toluene for that occasional bad batch of fuel.

Oh, and 8.6 DCR with alum heads is MAX with 93, at least in this ride. Right on the cusp.

Just an FYI. Must be something different besides the octane that is causing it for it to be that dramatic. I've run 103 on quite a few occasions and had good luck with it, but it was formulated for automotive engines. You've got a lot of other factors at work: vapor pressure, H/C ratio, O/C ratio.....

Mike