Hey everyone. New here and I had a question on the new L33 5.3 Gen III engines. I am looking to improve my engine a little and was just curious if anyone has stroked or bored out a 5.3 and by how much. Are there any specs available that tell how thick the sleeves are?
i think if i'm not mistaking the 5.3 block is an iron block so there is no sleeves. i don't know how far you can go with the 5.3 block but you can use the 6.0L iron block and stroke it to 4" and bore it to more than 4.060" to get more than 408ci.
__________________ Abdullah
2000 green M6 Z28 Mods: SLP flow pac, self ported LS1 heads with stock valves, TSP 233/239 cam, QTP 1-3/4" long tube headers, Borla cat back, ported Fast 90mm intake, NW 90mm throttle body, BMR adjustable panhard rod, BMR adjustable LCA's, BMR strut tower brace, BMR boxed SFC's, Koni Single Adjustable shocks, ES hyperflex bushings kit.
This is one of the new L33 motors with the aluminum block. They are just now coming out in the 2006 pickups as the Vortec 5300 H.O. engines. They are the same Gen III block design as the LS1, but I just don't know what can be done to them because no one has modified one yet I guess. They use LS1 based heads to, 2 valves per cylinder.
On the 6.0 block, what heads and intake do most people run and is there a "kit" for the 408 displacement someone sells? That has got to be an insane engine.
Thanks in advance.
--Will
Last edited by Will-Martin; 03-29-2006 at 12:30 PM..
for heads you can go with AFR 205 heads hand ported, go with a mild cam since you will need torque. for the intake i don't know about it maybe you will reuse the stock factory intake manifold. for us camaro/firebird/ corvette owners we like the FAST LSX 90mm intake with 90mm throttle body but i think this intake will not work in a truck unless you replace the wiring harness, PCM and sensors.
for 408 kit i also think maybe you can go with 6.0L LS2 aluminum block maybe it will work in your truck it can be stroked to 402ci and to 408ci max.
Abdulla, great posts, I'm going to overhaul my 2001 5.3 GMC. Will the heads work with a 6.0 LS2? Where can I get a short block? This seems to be the easiest way to beef up HP w/o breaking the bank.
L33 (Vortec 5300 H.O.) Crank 
