I rebuilt the transmission on my 71 442 and used the Transgo kit. I notice it shifts out of first and second around 4,000 rpm at WOT. I'm wondering how the car would accelerate if I was able to change the shift points to around 4,500 rpm? Its probably not advisable to go any higher with a fairly stock engine, correct? It is mostly stock other than a comp cam XE262H, higher compression pistons, about 9:25 comp ratio. I was thinking about trying different governor weights with the B&M kit. Anybody try this with positive results? If so did you also change the springs? Thanks for your input.

 

What happens if you manually shift it?

 

Good point, I shall try that. Sometimes one can't see the forest for the trees. Ha.
I think I read a car should shift around peak horsepower which should be higher than 4,000 rpm I would believe.

 

My experience is there is no real ET gain from reving higher, and the shift points you have should work great and safer.

Now does it kick down to a lower gear when you floor it cruising?? When kick down doesn't work the 400 usually shifts around 3,800-4,000, but that can be good.

 

In Drive, I always like mine to shift as early as possible. If I want to wind it out further, well, that's what the shifter is for.

 

I agree somewhat. My cars in factory trim have all shifted at 4800 RPM in drive (granted, all were 350 cars) and when I wanted a higher shift point I manually shifted. 4000 RPM sounds too low to me, though - 4500 or so would be make me happy.

 

Thanks for your input. I guess I was comparing to newer cars that rev out in each gear to near the redline, but then again they are overhead cams and get their power at high rpms, whereas the Olds engines are torque beasts. I was just thinking 4,000 was quite low on full throttle, and maybe 4,500 - 4,800 would be an advantage. I suppose it comes down to personal preferences.

 

The way to test for correct shift points is to start at around 4,000rpm shifts, and to raise the rpms by 100, on each run, till it doesn't run faster. Smaller engines rev higher normally, and must use deeper gearing to create torque.

Its the same with diesels and gas motors...

 

Two comments:

1/ The only way to know whether the higher shift points improve your performance is to test at a dragstrip. And your results will be meaningless if you can't launch consistently. Well, the ETs will be meaningless; the MPH will still tell you a lot.

2/ Make sure your tach is accurate before you use it to test higher, manual shift points.

 

I would suggest getting another govenor to modify, that way you dont mess up the only govenor available. Make sure you take detailed notes, its real easy to make enough chamges you csnt remember what you tried. It took about 10 tries to get my shift points where I want them, but any excuse to take the car out, put the loud pedal on the floor, and make some noise is good incentive.