How much overbore can the iron block stand up to??

I am thinking it could go 4.100 with no problem
since it is really only .050 off each side of the bore. And the block looks pretty thick to handle it.

Maybe more????

 

i think it was .040 for most, but SOME were able to go all the way out to .060

Chris

 

Got to be more than that. My 5.3L block is about .125 over. Not sure about the 6.0L block though.
todd

 

I think the max bore for all the iron blocks is 4.06"

 

i am pretty sure what i stated above is for the 6.0L block. todd, is your block resleeved? maybe that's why you can go over that far?

Chris

 

My block is not resleeved. The 5.3L has a lot of extra meat on it. Stock bore size is 3.780 for the 5.3L block. Mine is at 3.910. That comes out to .130 over by my math <img src="gr_grin.gif" border="0">
Todd

 

It is possible to bore a stock cast in liner completely out and put in a conventional stepped pressed-in liner to obtian SAFELY 4.080. Basicly known as sleeving. Or your floating on block material.

 

Golden West Performance was going to give me a 427 by boring 4.060 and 4.125 stroke. But, Kenny got uncomfortable with the 4.060 bore (he felt durability/reliability would suffer) and recommended I stick with 4.030.

So 422 it is.

 

I remember seeing .060over on the 6.0 liter block. don't know about the 5.3L block.

 

Evidently, the 4.8 and 5.3L blocks use different liners than the 6.0L block.

Certain 6.0L blocks can be bored over .06 after the cylinder wall thickness is checked.

I think I've heard of an iron block going out to 4.08 but, I don't remember where I heard this.

 

My 6.0 block is bored .060 over.

.030 over is no sweat, ditto for .040. But .060 will make you look at the coreshift a lot more.

I have heard of two 4.080 bore 6.0's but have no detail on them might be just rumors.