Coming Soon: 4L65RR Manumatic System

[Steve Chryssos]

Lots to digest here.
The 1-2 gear spread on a 4L60E (and 700R4) is perfect with a 3.42. But a 3.42 can be a little low (numerically) for overdrive and a 25.5" tire. Cam and converter selection becomes critical to avoid lugging in overdrive. fuel injection or a finely tuned carburetor helps as well.

The 200 has a great 1-2 split, but the .67 overdrive will exaggerate the lugging issue. I personally prefer the 200 over the 700, but consider swapping rear gears down the line if lugging (at around 45-60 mph is a problem. Swapping gears after finishing a project is normal.

Your tire selection and intended usage will help cushion your transmission choice. 550Ft-Lb torque capacity on the street with NT555's is different than 550 Ft-Lbs on slicks at the drags every weekend. Bowler rates their transmissions for worst case scenario.

A stock but fresh 4L80E with shift kit can handle 550Ft-Lbs of torque out of the box, If you find a good core at the right price, an '80 can actually serve as a budget solution. '80's, like TH400's, seem to take a little longer to complete shifts. And the engine braking feature is not yet available. Hence the high dollar 4L65RR. Quick, reliable, and with engine braking.

A $1000 700R4 will lack the hard parts necessary to handle 600Ft-Lbs. In fact, it will probably fail at 250 Ft-Lbs. Honest torque capacity costs money.

Brain overload. I'll re-read this tomorrow to see if I missed anything.
Thanks for looking