Help!!!!!!!!!!! 4.8l - 5.3l

[carnell]

I'm in the middle a rebuild and the machine shop just called and said that after measuring the block, he said that I have a 4.8 and not a 5.3. I know the blocks are the same but the cylinder walls are a different size right?

The wrecking yard said the engine came out of a Tahoe. Due to my work seclude, my wife picked up the motor and I didn't even think to tell her to ask to see the donor vehicle. I tore down the motor myself, so I still have all the parts. Is there another way for me to check to see if I have a 4.8 or a 5.3?

Thanks

Carnell

[SLO TRUCK]

its on the front of the block its cast into it. Like this.
Your machine shop is retarded. 4.8/5.3 is the same blocks, same bore, just different crank.

[carnell]

How much of a hit in performance will I take? My receipt says 5.3L not 4.8 so I have a valid reason to take it back. If I change the crank will it be equal to a 5.3? Is it worth the flight to take a back and get my money back?

[SLO TRUCK]

if this was just a rebuild not much. The 4.8 and 5.3 only had 15hp difference between them. My 4.8 made 450hp/450 tq on 10psi. Depends on how much performance you were looking for.

[PitchBlackC3]

What did the pistons you took out look like?

[carnell]

Bad call by the machine shop. The crank and pistons are for a 5.3L so all is good. I'm glad I had a chance to write you guys and look online, or I would have call the wrecking yard and looked like a ass!

Thanks guys for th quick help

Carnell

[zebra]

easiest way to tell with the heads off is if the pistons are flat-tops or not. 4.8 has flat; 5.3 has dished (except the L33 - it had flats too, but was an aluminum block)

[carnell]

I read that last night. I'm glad I took allot of pictures during the tear down

[Duct_tape123]

What is the CR of the L33? Wonder if its worth the work to switch the flat tops into my 5.3.

[carnell]

If you look at the pictures, you'll see that the pistons have rims, unless it's been rebuilt, it's a 5.3L. Due to wear, I had to get new pistons. I'm not sure if they are going to be flat tops