Quote:
Originally Posted by Japhy
Long story short, what I thought was the beginning of the end for my 95" harley motor w/high compression pistons (9:1) turned out to be a couple of gas stations up here putting 87 octane in the 90 octane tanks (I suspect). I finally narrowed it down when I noticed that it only ran rough, sounded crappy, lacked power when I filled up at these stations  . so tonight I filled it up again at said pump but added some octane booster and she ran like a striped assed ape again. Before you suggest just filling up at a different station, you need to understand that up in the Great White North there isn't a gas station every 5 miles. So, I hear some fellas run a toluelene mix to boost octane cheaper than the commercial products. Anyone have any experience with this? What ratios etc? Thanks, Japhy |
First. 9:1 is high compression on a Harley? That's boostable low compression on pump gas for a car.
Yes. Toluene works. It is about 114 Octane. You can "roughly" calculate your target octane as a simple average. I have a high compression Heads and Cam LSx motor in Vette (about 11.1:1 static). This fairy juice 91 we've got in CA don't quite cut it. After experimenting, I found that 6 quarts Toluene to 15 gallons Nancy-Pants 91 got me to knock-free Nirvana.
Some notes on Toluene
It's kinda fun to play with, especially if you're going for that "I have a meth lab in my garage vibe." It is ridiculously caustic, destroying plastics with minimal contact, and oh yeah, it causes cancer if you breathe in very much. Nevertheless, an effective octane booster. In fact, it's a key component of what refineries use to boost octane for different blends. Here in the people's republic of CA it is fairly expensive and only available from large paint stores (it's a specialty thinner) and chemical supply vendors. It might be rather cheaper up there.
But let me introduce you to my new friend.
Torco Mach Accelerator - Race Fuel Concentrate
It's a black box. Nobody knows how it works and it's a closely guarded trade secret. I can tell you this empiraclly. What took 6 quarts of Toluene, only takes 1 quart of Torco. Buy 5 gal cans (not cheap) to substantially lower your volume cost. You should be able to find a local distributor who will be cheaper than Torco direct though. Depending on how much you ride, it should last quite a while though. (I use 1 quart with 15 gallons of 91 to get to about 93).