Folks,

Odd question here. I've been trying out 76's 100-octane Race Gas, which is the only alternative to the sad 91-octane we're forced to use in California. It definitely feels like the car makes more power running on 100, but I'm finding that it also leaves significantly more soot particles on my rear bumper.

Anyone out there have any ideas? I suspect if there's a noticeable increase in soot, the cats can't be too happy either.

Thanks,
--arash

 

I would think that being the car most likely does not adapt the timing instantly, that you are not getting the max benefit of the octane. Maybe leaving a little timing on the table for now. I would run a solid tank through and see if you have any better results.

On another note, I'm not sure that soot is a bad thing. Just a product of combustion. I wish it was easier to get unleaded race fuel here. I guess the trade off is 93 at the pumps

Mike

 

It's your maps that are not compensating for the 100 Octane. If you run specific maps for the 100 Octane you may find that the exhaust discolors the tailpipe and potentially the paint back there. I run 100 Octane on the track a few times and my black tailpipes have a brownish tint to them now.

If I were you, I would mix about 1/4 tank of the 100 Octane with 3/4 of 91 Octane and that should get you to about 93 Octane.

Cheers.