Manual to Automatic

[96z28SideSwype]

What type of trans are yall running after swapping to auto I currently have a T56 and will someday go to a automatic when I start to get into bracket racing and want more consistent times. Right now Im just wonder what all you had to change in the drivetrain area to make it work and what did you have to remove to make the car start if you went from a manual to auto in general because I do have access to a Turbo350 right now but was wondering about a PowerGlide set up. Thanks guys and gals.

[Injuneer]

Depends how far you want to take it. We have a trans builder who posts here that can build a reliable 4L60E for very high HP. Trans/converter/shifter/console/flex plate/crossmember. Flash the PCM with an A4 program, get the harness for the trans, wire up the p/n stuff.

I opted for a TH400, reverse-pattern manual valve body, to handle 800 HP/800 lb-ft (and unfulfilled plans for increasing that). 4.11 gears and no OD was unbearable on the street, so I added a Gear Vendor OD. I tried keeping the T56, but my shifting was incompetent and inconsistent.

[96z28SideSwype]

I want to stay T56 as long as I can, before I get real serious into bracket racing. I know we have a trans specialist here. I'm not looking to go with a 4L60-80 Trans since I have a the Turbo350 already but im not interested in going with a powerglide setup and see if any here is using one and how much they like it.

[Jon114]

I went from a t56 to a coan th350 transbrake rmvb with 8" 4400 stall. I also have 4.11 gears in my 9" . Highway does suck but in town is fine/shorter distances. Other than that , i couldn't be happier! I was told our cars are too heavy for powerglide.

Sent from my SPH-L710T using Tapatalk

[CPT]

This will depend on a couple factors. What is the over all horsepower goal? How easy are you looking to make the swap? How much street driving will the car see? We can build a 4L60E to eclipse 1000 horsepower, but it would require a wiring harness change to control the transmission. A 700R4 could be adapted and you could use the factory 4L60E style speedometer and torque arm mount. This would require a swap to a '93 style throttle body with a throttle valve cable pivot point, TV cable bracket from a '93 and the correct TV cable. The trans will have to be rewired internally to allow the lock up to function and a 12 volt source and a ground would have to be ran to the transmission. The governor will also require "tuning" to get shift points correct. Both the 4L60E and the 700R4 are overdrives, with a .70 4TH ratio and a 3.06 1ST gear ratio. The TH350 is an option, but it's a 3 speed with a 1:1 high gear ratio and a 2.52 1ST gear ratio. This means it won't launch as hard as the 4L60E or 700R4. There's an adapter kit available that allow the use of a 4L60E style speedo and torque arm mount for it. The TH350 is cheaper to build, but the adapter kit can be pricy. The TH350 is also no stronger than a 700/4L60E. The TH 350 wouldn't require any wiring or TV cable. The other option would be a TH400. The 400 is also a 3 speed with a 1:1 high gear ratio, but it has a 2.48 1ST gear ratio You have a couple options for getting the speedo to work. Some wire it n the front wheel ABS sensor. The correct way to do it is to source an original 1990 454 SS truck VSS and exciter ring for the trans. You will also have to buy a new crossmember and have a driveshaft custom built. You will also need a way to mount your torque arm (some crossmembers move the mount to them). The Th 400 also requires no wiring or TV cable. The TH 400 is the strongest transmission ever installed in a factory vehicle. The TH 350 uses a "kickdown cable" for kick down only. It's not necessary to hook them up, but the trans won't have kickdown (passing gear) with out one. The TH 400 uses an electric solenoid for kickdown. On factory equipped vehicles, they had a switch under the gas pedal that activated it. Again, it's not required to hook it up, but you won't have "passing gear" without it. RELIABLE manual valve bodies are available for the 700, TH 350, and the TH 400. However, the 700 uses a reverse shift pattern and nobody makes a reverse pattern 4 speed shifter or gate plate. The TH400 is also the best candidate for a transbrake.