JonRad

Hi all! First time tearing down an engine. I’m fairly certain the cylinders need bored but looking for another opinion to see if it’s even worth it.
There was significant rust in 4 cylinders so I cleaned them up and hit them with a 3 stone hone. There’s still pitting in the cylinders walls. Feels smooth but you can see it for sure.
So, am I correct in saying it’s definitely needing bored out?


Before

Before

After honing

After honing
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Che70velle

iTrader: (6)

Internet pictures are always a gamble, but it looks bad. If you can feel any of the pitting, it will definitely need an over bore. Good news is that a 5.3 block can usually go pretty far out without any issues.

RB04Av

Looks pretty rough to me.

You can pick up a junk short block for cheaper than messing with a bunch of that.

Just because something "can be done" doesn't automatically make it "A Good Idea".

Jake Wade

Have it bored. Pictures look rough.

JonRad

What’s the average cost of boring?

99 Black Bird T/A

iTrader: (4)

Paragon Engines machine shop pricing gives a rough idea. Could be more or less depending on the shop of course.

Che70velle

iTrader: (6)

$40 a hole is average cost here in North Ga area. That includes honing with torque plate. It will vary all over the country I’m sure.

JonRad

What’s “with torque plate” mean?

99 Black Bird T/A

iTrader: (4)

Basically bolting the cylinder head to the block w/head gasket and torqing to spec cause the block to distort. So the machine work should be done with that stress simulated using a torque plate. Otherwise if the machine work is done without a torque plate the cylinder holes won't be perfect cylinders and perfectly round when the head is bolted down. When that happens obviously ring seal can be compromised. Many top notch shops often also bolt on an oil pump etc to simulate additional stresses to ensure best possible results.

Aluminum blocks with iron liners are very susceptible to this issue. However it also affects iron blocks without liners as well. I had a iron block 383 small block chevy that had horrible ring seal and one of the many issues was the asshat's that did the motor didn't use torque plates when boring and honing the block. You could see the resulting distortion in the cylinder walls when that 383 SBC was torn down.

More info...


LS torque plate

LS block getting machine work with torque plate in place.


gm-ls-torque-plate-by-maperformance

The torque plate is to simulate cylinder distortion that is present only when the cylinder head has been fastened to the engine block. It helps to ensure that the tolerances targeted and achieved during the boring and honing processes remain true with the cylinder head in place; A must for any application looking to exceed factory performance levels.

JonRad

Cool, just saw a video about that last night. Thanks for the education! Love to learn.