How hard is it to do a bottom end on a 5.7l 350 corvette tpi motor?
The owner of the car said it is the corvette motor and the valve covers have already been removed, is it easier for me to just bring the motor to a shop and let them handle it or should I do it myself. I am very interested in the car its a 89 Iroc Z28 blue with t tops for 1500. The Corvette motor just makes the car even more appealing.

 

The distinguishing factor between the vette motor and the 3rd gen 5.7 is the heads. The vette had aluminum heads and the 3rd gen had cast iron. There were other differences but that is the most notable. Lots of people think of the 5.7 as the "vette" motor. But in fact the 3rd gen was available from 87 on with a 5.7 as well.

As far as rebuilding the bottom end of an engine. My advice is perform the tear down, making sure to mark each rod and cap as to the cylinder they go to. Keep each cap with the rod it came with. If the motor has been apart before, they may already be marked. Take the rods, with pistons attached, (because you don't want to try to detach them if you don't know what you're doing), the crank and the block to an engine shop and have the rotating assembly clearanced and balanced and the block tested for cracks(magnafluxed) and machined. A good machine shop will give the block back to you with the cam and main bearings already installed and hang new pistons on your rods and prepare your crank all for about $750. It's a bargain. Then you put it together.

Doing the job yourself without machine work is a huge gamble. Unless you have all the right tools for measuring roundness and taper, there is no way to be sure of proper fit of your parts. Plastigage just isn't the same. Balancing the assembly requires a specially set up lathe and weights. Plus, a good engine machinist can give you solid advice on special tricks, like clearancing the block for a double roller chain and boring with torque plates.

 

Thanks for the help.

 

If you re-assemble the short block youself, you will need a torque wrench, ring compressor, and a micronitder w/a magnetic base to check crankshaft end-play.

Be sure to lube everything....cylinder walls, rings, rod & main bearings, and camshaft. Oil will work for the rings & cylinder walls, but you will need assembly lube for cam & bearings.

Make sure you put the upper and lower bearing halves in the right place, also make sure that the fillit side of rod and rod bearings go to the fillit side of the journal.

Do a search for torque specs.

 

I won't be buying the car anymore, it sold today.

 

also the vette motors had 4 bolt mains while the thirdgen motors had 2 bolt mains...