I`M READY TO BUY A 400 TRANNY,DRIVE SHAFT&12 BOLT POSI REAR END& A 455 BLOCK DISASEAMBLED NO CAM OR CARB IS IT WORTH IT.THANKS DONT WANT 2 START OFF IN THE HOLE ALREADY

 

What it is worth is based off of what you want to use it for and how much work you have to do to get the engine ready. Do you have a camshaft and carburetor for the engine? Does it have everything else besides these two pieces or are you going to have to buy all sorts of accessories as well? Just off the top of my head I would probably pay about $600 for the pieces you mentioned if the entire engine is there minus the carb and camshaft.

 

IT COMES WITH EVERYTHING EXCEPT CAM & CARB ,SO I`M BUYING THE ENGINE &TRANNY,DRIVESHAFT,POSI REAR END 342.THANKS

 

My personal opinion:
1/2 an engine: I'd give 100 bucks not knowing wtf is up with it.
maybe up to 400 if there is great paperwork and decent heads
unknown th400 core 100-150 bucks

Useable driveshaft 50 bones.
If you don't need it or it wont fit, don't get it.
A non effed up posi rear 10 bolt 2-300 bucks
12 bolt 2-600 ucks depending on whose parts are in it, and what shop set the lash etc.

Final fair cost: $450-1000

Anyone else wanna chime in?
I have no idea what any of this is out of or going into though.

 

It all depends on the condition of the parts. In my part of the country if the posi is good and would run as is $500 could be a going price. Wrecking yards would want $250 for a running short shaft TH400, but they would also provide a guarantee. I can hardly sell one for more than scrap since I'm a private party rather than a business. You didn't mention what year the parts are, things such as what kind of heads come with the engine? Does it have the W/Z exhaust manifolds? If you need these parts for a car here's a chance of getting them all together. You might have to spend several saturdays scrounging wrecking yards before you find a Cutlass/442 driveline for a TH400, if that is what this all came out of. So, all that to say you could be looking at treasure or a lot of headaches. I would certainly have the money in my pocket and get over there to inspect it as quickly as I could, if this is all good stuff it may get snapped up quickly. I tend to be an optimist and hope it's treasure, and maybe half the time it is. My 2 cents!

 

Costs for trans and rear are dependent on application. I've noted some cost for A-body below. The A-body will cost you more than full size.
Not sure what region your in or if that will make a difference. In CT, a BOP TH400 short tail will cost you $50 - 600 depending on condition. A good used driver with torque convertor I'd estimate $200-350. Long tail 400's are significantly less expensive.
Drive shaft (A-body TH400) - $50.
455 core complete carb to pan/flex plate to fan - $400
Good running 455 complete as above (no smoke, run in vehicle before pull) - $1000
3.42 posi rear core (complete but needing rebuild) - $150-200 (assume 12 bolt type O posi). 3.42 posi any 10 bolt A-body BOP complete and functional $350-600. Any A-body 12-bolt chev. posi rear will cost you more - say $650-750 for fair condition. I haven't found anyone that will negotiate when selling an A-body 12-bolt chev posi rear. People treat these like gold.
Sorry for the bad news. Or good news if your about to score some cheap parts.
(disclaimer - I'm not the one selling the stuff to you)