I ran it on my truck once so far, and the results were promising. I did a few blasts at 20psi, only with a couple degrees of knock retard showing at the initial stab, and decaying the whole run. The truck will definitely show more knock than that with pump gas, I'd see 8-10 degrees of retard at 17-18psi on 93 octane before.
It's getting cold (and rainy
) around here, and I installed a bottle heater to keep the pressure up. Unfortunately it stopped working, and I'm waiting on a new one, so I can have consistent bottle pressure while I am testing. During the short time I used it, I saw the pressure in the tank drop from 106 to like 88psi, after a few spurts of it. This was in 35-40 degree weather.
The kit is really nice, and offers some great adjustability.
One thing worth noting is that the turn on of the propane is really invisible compared to alcohol. In the installs of alky I've done, if you do a test shot of it, or turn it on too early, you'd really notice. I had the propane set at a high duty cycle, and the turn on set low (while I was adjusting it), like 2-3psi... propane came on, and I just barely noticed it. Once I turned the turn on point a bit higher, it was really transparent.
Anyways, I'm waiting for a new tank heater, and some dry streets, before I do more testing. I should have some wideband 02 data to go with it as well, which will be valuable since from my reading, the sensor works fine with the propane, just have different air-fuel ratios to shoot for.
I'll post here when I have some more info, I'll play with it more in the next week or so, weather permitting.
This directory has some pictures of my setup installed, and the rest are the pics Jay has posted before.
http://www.chitownsyty.com/bg/pics/propain/
Oh yeah, FYI, it cost $4.65 to have my tank filled
That is so much nicer than $5-8 bucks a gallon for race gas.