[Jackpine]

Originally Posted by 38Blackfin

New Gryphon 5000 miles ago, 87 Perf custom tune, 2008 SCrew 5.4, Gotts, Mag SISO, stock cats and y-pipe, 100,000 miles.

New plugs, fuel filter, everything else original, throwing no codes. Did the BG clean thing for the injectors, MAF, TB about 10,000 miles ago.

3 things:

Flat spot 15-1800 rpm, right after a shift typically, push a little harder, drives through it.

Smells lean at start-up. Most 50+ yo's will know what I'm talking about

Slight knock at hot start, sounds like spark knock.

Other than that runs great, 17-18 mpg average.

thanks!

Randy

Great mileage! I get 15.1-15.5. I don't have your "flat spot". I wonder if the Torque Converter is locking up too soon? Have you monitored that? And if it is, you can adjust the part throttle lock/unlock points in the Custom Options.

I also don't have the spark knock at hot start or the "lean smell". I doubt this is a significant worry, since it is a fairly momentary condition.

Did Bill try to write you a tune to maximize economy?

I really only worry about spark knock under load, or at cruise.

- Jack