[Batman]

Are you sure it is shifting too soon? Just cause you aren't at your max RPM doesn't mean it is shifting at it's ideal shift point. If your motor stops making power at 5250 and you rev it to 5750 you just wasted 500 RPM. I don't know the TPI engines as well as I should so I can't tell you what the ideal shift point is but I do know higher RPM isn't always better (sounds cool though!). You need to figure out the power curve of your engine, factoring in what gear ratio's you are running and experiment to find your ideal shiftpoints. If I remember correctly TPI engines make very good low end torque and so-so top end HP (I am talking stock so don't jump on me!) so i would think if you have a decent rear gear ratio you would benefit more by getting the engine back into the fat part of the torque curve by letting the car shift sooner. Where as if you have a cam that puts the power up top you would want to rev it out as far as possible to keep it in the power curve. You can't always go by seat of the pants either. Take the car to the track, make at least 5 passes with the car shifting (so when you blow the 700-R4 power shifting it you may still get a comparison) then go ahead and rip away at it till your little heart is content for 5 runs. Average the numbers (don't just use peak numbers) and that will show you which way is better on average. The more runs in your comparion the better but do them in the same day because weather and track prep will also be a factor on any given day. Also try and keep cool down periods about the same so the trans is roughly the same temp. That's how I did when I still had the M6 (testing different launches and shift points) and I went from running 12.5's into the 11's with just some experimentaion on the same set-up (were talking close to a second in the 1/4). Speculation is fine but until you get out there and put it to the test you will never know.But my money is on the computer beating you, especially if you have a shift kit..