Hey,
I just bought a 89 RS with a 305 that purrs. Problem is that the Transmission(700r4) only has reverse. My intentions in the future is to have my 400sb in it paired to a th350 that is rated up to 500hp. The 400 was dynoed at 450hp. So right now I just want to put in the th350 and enjoy the car for the summer before I fully convert it. Any thing I should be aware of when doing this swap.
Jimmy

 

the drive shaft and rear end will need upgraded or that power will tear it to shreds...

 

you will have to buy a kit to mount the torque arm because it mounts to the tailhousing on the 700R , you can get them through Summitracing for a decent price , the drivehshaft will have to be lengthened because the 350 turbo is 3" shorter than the 700R and as Shmack2004 stated the 7.625 rear diff. in the car won't live very long with 450hp and the torque of the 406 , usually 406's are torque monsters and you will break the rear diff. with little abuse

 

Thanks.
I remembered that I acutally have a TH350 that was in a 3rd gen and it had a special kit the guy had on it to fit. I will have to get the Driveshaft resized. I don't plan on putting the 406 in until the car is ready for it. The 305 still runs nice so I will enjoy it with that while I save up for a aftermarket rear to handle the additional power.
Thanks again guys.
Jimmy
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