here's the deal. my truck is starting to smoke a little on start up, probably the vavle guides leaking but with 159K in the truck im a little worried about the rings and bearings in the bottom end so im thinking about building another motor to drop in when mine goes.

what is the difference between a 5.3 bottom end and an ls1 bottom end? from what i can tell just the bore is different. if i bore a 5.3 block to a 5.7 with some slightly domed pistons (or should i go with a stock 5.7 piston?), 706 heads milled .030", tr224 cam, and full boltons what should i expect? is it worth the time and money to build a 5.7 or should i stay with a stock displacement? also, i will be keeping the stock intake if it matters.

 

or should i build a 6.0 with the stock bottom end, same tr224 cam and milled 706s?

keep in mind this is still going to be my daily driver and i do drive quite a bit so i dont want to sacrafice too much gas mileage or get too radical, i will be towing with the truck as well as attending track days....i use my truck for everything

 

6.0 with worked 317s would be the best for the money imo

 

what junk yard has the engines for like $85? im assuming 5.3s are easier to find than 6.0s out there?

i already have the heads, cam and pretty much everything to swap them to my engine, i just want a fresh bottom end too

 

no other input?

 

i built an ironblock 5.7... machine work cost me 380 total... picked up a 4.8 for 300... but the crank i had to buy from a buddy and he sold that to me for about 75 and then the pistons i bought for 40 from a guy down the road from me...

 

If you would've picked up a 5.3 you could've used the stock crank

 

the 5.3 crank and rods are the same as an ls1, right? only the bore is different?

 

Yep; physically the same but a real LS1 crank has holes to lighten it I think......or something like that.

 

I think the crank will need to be rebalanced for the LS1 pistons.