the guy that set up my transmissions shift points set it so the car will shift at 5500 at hard acceleration. someone told me i am loosin power because the cars top peak in horsepower is 4400. i was wonderin would it be better to set the shift points so it changes gears at 4400 and wouldn't that give me better takeoff and acceleration???

 

In most cases you shift 10-15% above the power peak, that way after the shift you are on the other side of the peak by about the same distance rpm wise. You are looking for the highest average horsepower in the peak horsepower curve.

 

SO on a 1988 irocz 350 tpi 700r4 tranny and 2.77 reaR END WHATS A GOOD SHIFT POINT?

 

"SO on a 1988 irocz 350 tpi 700r4 tranny and 2.77 reaR END" What is YOUR power band? When does it start to level off? I like it to start the shift just before it begins to level off since at that point you have for all intent and purpose, stopped accelerating, or at least at a lower rate.

For example, a typical TPI will flatten out at 5000 RPM and a typical carb 305 will flatten out at 4000 RPM. In both cases you will see tachs that go 500 RPM higher than thatbut unless it PULLS strong up to that RPM you may find that your car feels better with a lower WOT shift point than that. Again it is up to you to decide what your car does, not just pick an arbitrary number.

 

it depends on YOUR cars powerband....

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305, TPI,compucam 2030 cam, air foil, 8.8 wires, accel super coil, dynomax headers, custom y-pipe, cut out, 80 series flowmaster, just installed my 3.08 posi disc brake setup...(3.42-3.73 on the way). and a stage 4 chip :0). hittin a sad 15.1 after the chip with 2.73 open diff....

 

Go to a Drag Strip and find the best shiftpoints for YOUR CAR. Even a dyno test won't tell ya. My car at the most changes maybe a tenth of a second ET with different shift points between 4500 and 5500 rpm at the dragstrip. But if I shift it higher than 5500 it slows down. ET. If your car is near stock you won't have to shift very high for best acceleration. Lot's of times the "Butt Dyno" can be very deceiving.

[This message has been edited by F-BIRD'88 (edited November 10, 2001).]