I have heard that you can open a 5.3 up to a 5.7 bore and since they have the same stroke, you will have an iron block ls1, in theory. anyone with info on this or that has done this? i have a 5.3, and im looking to run a front mount turbo on 10 to 12 lbs and i want to use all stock internals, besides valvetrain mods. i was mainly worried about durability issues with that much overbore. anyones $.02 would be great.

 

all 5.3L blocks were designed to go to 5.7 you won't have any problems

 

there are a few people that have done that

cyaz06 - radix
Blown06( i think thats his name) - procharger
Curtd - front mount turbo
Brian@JPA - sts turbo

im sure there are others but i cant think of them at this time

the main reason for doing this is so you can use shelf pistons on the 5.3L block and not have to pay out BIG money for custom pistons

 

Mine seems to holding up great, and I haven't been easy on it.

 

How much meat do ya need to grind out, .120"? Or not quit as much? Is there anything inbetween...................

 

Just buy a used LS1 shortblock. You can find them for $300-$500 easily.

 

You must have better connections then me, cuz people seem to think anything LS1 is gold. My machine shop guy gets $400 for just a block, were he told me $250 for a 5.3 block and crank.

 

3.779" 5.3 bore size
3.905" 5.7 bore size

.126" over bore.

 

Just keep an eye on LS1tech for sale section. I saw one for $250 a month ago or so. I almost sold mine for $400 before I decided to keep it.

 

Wow you must be showing me all these good deals because you made this exact post 3 months ago in another thread I was interested in.

Here's what you put:

If you actually have links to this stuff then post them, otherwise I'll assume you're full of BS. It's one thing to want to help out but don't be throwing lies out there to sway people away from other ideas.