89 rs th350 crossmember questions
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Car: 91 camaro rs
Engine: 305 (350 vortec in dec.)
Transmission: Wc-T5
Axle/Gears: 3.08 (3.42 in dec.)
89 rs th350 crossmember questions
I have a friend building an 89 rs, has a 68 camaro 350, bolted to a th350... His question is is there a tranny crossmember that will bolt to our cars, but work with a th350.... That doesn't cost $250+? any help would be great, thanks guys!
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: 89 rs th350 crossmember questions
Our cars never came with a TH350 option so there is no factory bolt in item that will work.
Before swapping in the TH350, is it a long or short tailshaft? The long tailshaft can reuse the 700R4's driveshaft but the short tailshaft needs the longer driveshaft from a 82-83 third gen with the 200c 3 speed tranny.
The other conversion problem is the torque arm. There isn't a mount on the back of the TH350 to install the torque arm. That's why it's always best to buy an aftermarket torque arm that comes with the proper crossmember for the transmission you want to use. The aftermarket setup will mount the torque arm onto the crossmember where it belongs and not on the back of the transmission like GM installed it.
If you want to fabricate something yourself, all you need to do to the crossmember is relocate the mount that the tranny sits on 2" forward. A simple gusset welded onto the crossmember will work.
After all that, you still need to install and adjust a detent cable and run a manifold vacuum line down to the modulator valve. Your 89 probably has an electronic speedo so the TH350's cable driven speedo will need to be converted or adapted.
Before swapping in the TH350, is it a long or short tailshaft? The long tailshaft can reuse the 700R4's driveshaft but the short tailshaft needs the longer driveshaft from a 82-83 third gen with the 200c 3 speed tranny.
The other conversion problem is the torque arm. There isn't a mount on the back of the TH350 to install the torque arm. That's why it's always best to buy an aftermarket torque arm that comes with the proper crossmember for the transmission you want to use. The aftermarket setup will mount the torque arm onto the crossmember where it belongs and not on the back of the transmission like GM installed it.
If you want to fabricate something yourself, all you need to do to the crossmember is relocate the mount that the tranny sits on 2" forward. A simple gusset welded onto the crossmember will work.
After all that, you still need to install and adjust a detent cable and run a manifold vacuum line down to the modulator valve. Your 89 probably has an electronic speedo so the TH350's cable driven speedo will need to be converted or adapted.
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Car: 91 camaro rs
Engine: 305 (350 vortec in dec.)
Transmission: Wc-T5
Axle/Gears: 3.08 (3.42 in dec.)
Re: 89 rs th350 crossmember questions
Sounds simple enough, so all I need to let him know is we need to determine if it's short or long. Everything else seems simple at that point, thanks
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