So I built a 383 out of my lt1 and wanted to get rid of my 6plans speed. I have a built turbo 350 with a reverse Manuel. Valve body. Will it bolt up and do I need to do anything special like get my driveshaft fitted or will the stock one be fine?

 

What tranny do you have right now? Is is a 6 speed manual? If so, why would you want to get rid of it? Just curious.

I am not completely sure, but there are a couple different tail shaft housings for the TH350 and there is a couple inches difference with them. I believe that you can get a tail shaft housing that will make the overall length of the TH350 the same as your 4L60E.

I believe that you should be able to just bolt them up to the LT1 block. I am basing this on the fact the TH350 and 700R4 were both available on Gen 1 SBC engines, and the LT1 uses a lot of the external dimensions of the Gen 1 block. If the bolt pattern is different, then someone has to have an adapter plate available. If the overall length is the same (depending on tail shaft housings) you can use the stock drive line (obviously).

I also believe that you will have to tune your PCM to ignore all of the tranny inputs and data (assuming you have an auto in there now - if manual then ignore), but that won't be an issue as you have to have a custom tune for the 383 anyway.

 

the tranny it self will bolt to the engine.
but you need

a th350 tranny mount
a new dipstick. madman has a nice one. thats what i have
a new drive shaft. i had to for my th400 swap from t56
a new flexplate.
a th350 torqe covertor for the same bolt patter on the flex plate
a vss in the tailshaft of the th350 for the stock speedo to work
and a tranny cooler.

idk if you have any of these parts but thats all you need

and why are you going th350 again. its not going to like the street. mine doesnt like the hwy or freeway but its nice to race thou.

hope this helps

 

...and a frame mounted torque arm bracket. I'm curious too why you want to get rid of the 6 speed? Wanting to deflate the value of your car can't be the only reason!
Also, there are three different tail shaft lengths with the TH350: 6", 9", and 12". Which one you have will make a difference on your driveshaft fitment; if it has a 9" tail, it's about 5/8" longer than your current trans, and slipping it in place would be a "close one".

 

Wow, going from two over drive gears to none is a big step. With the 3:73 and no over drive your doing about 4200 RPM at 75 MPH?

 

Its mostly gonna be a drag car. Im getting rid of the 6 speed because I bracket race and im sick of it kicking me out of 3rd gear and automatically losing the race because of it.