TH350 to 1991 RS
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Joined: Sep 2009
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From: Middletown, NY
Car: 1991 RS
Engine: 350
Transmission: 350 turbo
Axle/Gears: 3.73
TH350 to 1991 RS
Just bought a TH350 to put into my 1991 RS. Will I have to buy anything or any kind of adapter to attach to my drivetrain properly? can you link me to the part?
NOTE: THe RS had the 3.1v6 (if it makes any difference).
NOTE: THe RS had the 3.1v6 (if it makes any difference).
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Joined: Jul 2009
Posts: 236
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From: New holland, PA
Car: 1986 Camaro
Engine: 436" SBC
Transmission: TH350, 8" Converter
Axle/Gears: S60 with 4:11 and Locker
Re: TH350 to 1991 RS
you will need a bracket that attaches to the tail shaft of the tranny for the torque arm. I have one if interested.
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Joined: Jul 1999
Posts: 17,271
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: TH350 to 1991 RS
I'm not sure if the bellhousing bolt pattern on the V6 is the same as the transmission. I'm guessing it's not.
If you have a long tailshaft TH350, you can reuse your driveshaft. If it's a short tailshaft, you need a driveshaft from a 82-83 third gen that came with the 200c transmission or you'll need to get a longer driveshaft made.
You'll need to modify the transmission mount because the TH350 mount is about 2" forward from where a 700R4 mount is. The torque arm needs an adapter bracket to attach to the transmission.
Many swap problems can be solved by buying a new aftermarket torque arm. It will come with a proper crossmember for the tranny and the torque arm will mount to the crossmember and not the tranny.
You'll also need a proper tranny detent cable bracket for the engine and provide a manifold vacuum source for the modulator valve.
If you have a long tailshaft TH350, you can reuse your driveshaft. If it's a short tailshaft, you need a driveshaft from a 82-83 third gen that came with the 200c transmission or you'll need to get a longer driveshaft made.
You'll need to modify the transmission mount because the TH350 mount is about 2" forward from where a 700R4 mount is. The torque arm needs an adapter bracket to attach to the transmission.
Many swap problems can be solved by buying a new aftermarket torque arm. It will come with a proper crossmember for the tranny and the torque arm will mount to the crossmember and not the tranny.
You'll also need a proper tranny detent cable bracket for the engine and provide a manifold vacuum source for the modulator valve.
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Posts: 49
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From: Pleasant View, TN
Car: 89 camaro rs
Engine: carbed vortec 355
Transmission: upgraded T5
Axle/Gears: 3.42
Re: TH350 to 1991 RS
B&M sells a kit that comes with a bolt on mount for the torque arm, and it comes with a bracket for the tranny mount so you shouldn't have to modify it. i used this kit on my 89 camaro. is was pretty easy. i had to modify the torque arm mount slightly. other than that it was really easy. you can get the kit through summit racing.
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Joined: Mar 2002
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
Re: TH350 to 1991 RS
if you hyave a 700r4 or t-5 then i hope you got a '73-up 2wd truck 9" tail th350 so you dont have to swap driveshaft for a hard to find 82 83 200C one...
some vans and some wagons were 9" also, but not all of them..
most ppl dont know or realize there are several lengths of the th350 including 6" 9" and 12" over the years in 2wd form
6" is for 82 83 200c
9" is for t5 and 700r4
bracket for mounting the Tq arm is available form summit etc
i used a summit one in my 82 from 200c to th350
was 75 bucks when i did the swap
and only needed one of the two brackets they sent me
but 700r4 or t-5 to th350 uses both the brackets i believe
very simple easy to do
the trans pretty much put itself under the car
as if it was original
are you saying the th350 was on a 3.1L engine ??
im not too sure that any 60 degree th350 were ever made..
ive never heard of or seen one..
3.1 is a problem because it is 60 degree bellhousing
if it is a 60 degree trans and you have a v-8 then youre in trouble.. because the v-8 are 90 degree pattern..
and even if it is you still are gonna have to get a 200c shaft or a 9" tail th350 because there is a 3" difference from most car th350 to anything t-5 or 700r4
so hmm..
some vans and some wagons were 9" also, but not all of them..
most ppl dont know or realize there are several lengths of the th350 including 6" 9" and 12" over the years in 2wd form
6" is for 82 83 200c
9" is for t5 and 700r4
bracket for mounting the Tq arm is available form summit etc
i used a summit one in my 82 from 200c to th350
was 75 bucks when i did the swap
and only needed one of the two brackets they sent me
but 700r4 or t-5 to th350 uses both the brackets i believe
very simple easy to do
the trans pretty much put itself under the car
as if it was original
are you saying the th350 was on a 3.1L engine ??
im not too sure that any 60 degree th350 were ever made..
ive never heard of or seen one..
3.1 is a problem because it is 60 degree bellhousing
if it is a 60 degree trans and you have a v-8 then youre in trouble.. because the v-8 are 90 degree pattern..
and even if it is you still are gonna have to get a 200c shaft or a 9" tail th350 because there is a 3" difference from most car th350 to anything t-5 or 700r4
so hmm..
Last edited by Randy82WS7; Oct 6, 2009 at 01:30 PM.
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