so what kinda gains would you guys think if i bored out my 4.8L go from 3.78 to 4.00 and polish the heads???

 

Hey, you mght as well just pick up a 6.0 liter LQ4 or LQ9 long block. By the time you add up everything it's cheaper to get a 6.0 liter, then sell the 4.8 you have. Plus the 6.0 already has a 4 inch bore. A 4 inch bore with a 4.8 crank would be pretty wild though, it would rev like a sob, but the low end would probably be kind of weak for a truck.

 

I think the 4.8L block can only go out to around 3.9". The 5.3L block is the same.

 

that's correct XLR....basically if you bore a 5.3 to the max you'll have an iron block equivilant of the LS1

 

Thank you Slowverado

 

That's what I thought, didn't want to pull **** out of my *** in case I was wrong though. lol

 

any time XLR8NSS....

 

Becareful smarting off...this thread may get locked too!

 

Well, you can go larger than 3.9xxx, but why risk it. To my knowledge, nobody has done a larger bore than a 3.9 simply because the 6.0 blocks availibility.

 

Thanks for the info, folks! I posted a similar thread in the Internal area and got some good replies. I am about to bore out a 5.3L to the 5.7L 3.898"/99mm slug size. I got the 5.3 very cheap so theoretically I will end up with an LS1 cast iron motor in the Silvo for the cost of boring and honing. V8, the 4.8L block is the same as the 5.3, the only difference is in the stroke ( crank and rods ). The 5.3 has the same stroke as the 5.7 LS1 motor but smaller bore ( 3.78"/96mm ). You would need to get a rotating assembly/5.3 or 5.7 short block to get the benefits of this "stroker" 4.8 motor.