i have a 87 z28 with the LG4 305 in it. I will be swapping to an 86 350 engine soon. i have the engine but needs rebuilt. both engines are carbed. the 305 that is in my car now does not have a vacuum dist. but the 350 will have. I also plan on swapping the 700r4 for the 350 turbo i have laying around. i know about the 9" and 6" tail differences already. different drive shaft is no big deal. my main concerns are about the TC, ECM, Engine mounts, tranny mounts.

With the vacuum 350 and the 350 turbo tranny, can i just yank out the ECM?

What do i do about the TC since im swapping trannys as well, the TC is for highway fourth gear switch right? so the 350turbo doesnt have a fourth gear... so do i need to do anything with he TC? ( I dont know much at all about trannys )

If i decide to keep the stock 700r4 will the engine bolt up? since the new engine will have a vacuum fed dist. what do i have to modify there?

What about the X-member for the new tranny?

 

You don't need a computer to keep the 700R-4. There are several ways to control the torque converter lockup. You can find instructions on how to DIY rig it for automatic lockup in 4th gear, or there are simple kits on the market, with their own instructions included. Either way, while you're at it, do a fresh filter to extend the life of the trans.
Better to keep the 700R-4, it will improve both acceleration and MPG compared to that ancient TH350.
About your engine: Your '86 350 probably has a pair of #624 heads, and dished pistons. If so, trash those heads, and use the #081 heads that your '87 LG4 should have on it. Top with an Edelbrock 2104.
Then using the vacuum advance HEI distributor will let you remove the computer.

 

The 700r4 Thats in my car shifts hard and mite need rebuilt. I don't want to do that. If I put in the th350, will I need to do anything with the TC? since there is no 4th gear?

 

Shifts hard, huh? Count yourself lucky that someone already did a shift kit for you. Once you get that 350 in, it'll probably bark the tires like it should.
But if you want grandma shifts, just get a new 1-2 accumulator spring, and a stock pressure regulator spring, and a stock boost valve. You can probably find all 3 of those, used, for free. Installing them can be done using the online instructions for shift kits, only remember you're removing good stuff and installing lame junk.
Sell the TH350 to some un-enlightened old-think gray-beard, and have that money for things that will actually help your car.

 

it shifts hard shifting out of first gear. the other gears shift smooth. it will chirp the tires into second gear with only half throttle . and im not sure about other third gen camaros and firebirds but i can move my shifter from 1-2-3-OD like a manual car. dont have to push in the button on top of the shifter or anything. just moves freely.

 

lol this is awesome lol