[Christ]

Metro - Sorry about that, but I'd hate to add it, then get rid of it, and at this point, we're still unsure of what we're doing with either vehicle, hence the reason that not even basic mods have been made.

I suppose, at some point, it will become necessary to step back, take a look, and realize that I'm not benefitting anything by being undecided, and I either need to jump into something, or stick with what I have. There are large life-factors involved though.

The thing I'm asking about here, is essentially P&G - without using neutral. My wife's GP idles @ about 1200 - 1500 RPM while in drive - slightly higher than normal - when your foot is off the gas pedal, and you're coasting. The engine isn't dragging the speed down at this point, it's a GM thing, the engine idles higher while moving to compensate for potential load.. in case you hit the gas suddenly.

What I was wondering - regardless of speed - was if this is sufficient for a P&G situation where fuel mileage gains might be noted.

The problem with this, immediately noticeable, is that the TC locks to ~1500 RPM at 45-50 MPH, and doesn't go up much until around 70MPH, but under heavy accel, the TC won't lock, so I end up hitting engine speeds up to 3krpm during the acceleration, at only 30% throttle (to prevent down shifts).

Even if the TC does lock during acceleration (happens occaisionally), it unlocks as soon as there is no load - I let off the gas pedal to coast down - which means the next pulse speeds the engine to ~3krpm again, if it doesn't re-lock.

I'd love to control the locking phase of the TC manually, so I could accelerate at ~1500-2000 RPM up to 65-70MPH, then coast down at 1200-1500 RPM.

Make sense?

I'm going to try it out on the trip up to visit family, and if it doesn't work out, I'll just drive back with another method.