lbstone
Full Access Member
I've had my B&G PCM tuned for 93 octane for several months now and have noticed a bit of a "rattle" at WOT or close to WOT at RPM above 4K. I was thinking it might be something called sympathetic harmonic vibration. My reason for thinking this is the new PCM, in my truck at least, causes a bit more engine noise and vibration. I was thinking the noise was some heat shroud shaking or something of that sort. Its hard to pinpoint where the noise is coming from exactly due to the racket the truck makes at WOT anyways. I've never heard a motor knock at WOT so I don't know it this is similar. At idle and free reving theres nothing. Well, me being the lazy ass that I am, I decided to just go to the local Mobil Gas Station and pump in some CAM2 100 octane unleaded racing fuel. I was on Empty with my fuel light on so I figured the timing couldn't be better. After putting in only 7 gallons (it's $7.70 a gallon) I took her for a spin. I drove about 2 miles to let the gas mix and get fully pumped into the motor. I ran WOT twice through a few gears(and yes I hit 3rd!!!) and noticed no "rattle". Now the air is very cold and dense tonight which could make the difference. It currently 36 degrees. The water temp was at 200 degrees with the oil at 180 ish. Everything seemed fine with no rattle. Before I was able to duplicate the "rattle" with the oil at 160 and the water at 180 on a 40 ish degree day. I'm heading to work for a few hours of OT and will try and duplicate the rattle with the CAM2.
BTW, here's a description of CAM2 - "Cam 2" is the generic name used for Sunoco Race Fuels. You can expect the same consistent high quality performance from Cam 2 Racing Gasoline that you get from Sunoco Race Fuels because the names are interchangeable. It is the same product, made in the same facility by the same people. We use this name wherever the "Sunoco" brand name cannot be used, such as gasoline outlets which carry a competing brand of street gasoline. Cam 2 is available in 110, 112, and 116 octane leaded, and 100 and 104 unleaded. Please refer to the specs and MSDS for the Sunoco fuels listed above.
BTW, here's a description of CAM2 - "Cam 2" is the generic name used for Sunoco Race Fuels. You can expect the same consistent high quality performance from Cam 2 Racing Gasoline that you get from Sunoco Race Fuels because the names are interchangeable. It is the same product, made in the same facility by the same people. We use this name wherever the "Sunoco" brand name cannot be used, such as gasoline outlets which carry a competing brand of street gasoline. Cam 2 is available in 110, 112, and 116 octane leaded, and 100 and 104 unleaded. Please refer to the specs and MSDS for the Sunoco fuels listed above.