So I'm going to pick up a 5.3 out of a 08 Tahoe, got a good deal so I'm gonna do a few mods on it and throw it in my Tahoe.. After doing some research I decided to just stick with the 5.3 instead of going with a 6.0 or bigger, hell I would've bought a 4.8 if I could've found one! Anyways, so from what I've read the stock bottom ends on these motors are golden for the hp/TQ range I'm looking to make 600-700rwhp. I was contemplating going with the wiesco forged 5.3 drop in Pistons, but really don't see a need to for what I'm wanting. I'm planning on keeping everything stock on the bottom end except for gapping the factory rings. The oil pump is a high pressure oil pump, because it's a AFM/DOD motor, so I'm leaving that alone as well. I'm gonna do the ls7 lifters ( or if anyone has a better suggestion) ls9 head gaskets, pac 918 springs (suggestions?), arp head studs or bolts (suggestions), and a aftermarket cam. The cam I know nothing about, so input is greatly appreciated! I'm willing to have a specific spec cam done for my setup, just need suggestions on who? Also I don't wanna lose a lot of low end, this is in a 5,700lb truck (with me in it).

I can get a set of 317 heads if they would be a better choice over the 799/243 heads that are on the motor?

I'm going to swap this motor with my current motor when I'm done with it, and turn the boost up to around 12-13. Looking to get around 630 to the wheels on this setup and boost level.

 

799/243 is the best cathederal port that gm makes. Now the 317 head is supposed to be the same as the 799/243 but with a bigger combustion chamber. Choda just cleared 100k miles with boost around 12 psi and my brothers truck has about 30k on 11psi all stock with dod turned off.

 

leave motor alone, add gaskets and studs
at that power level no need to gap the rings

i run a ISKY 218/218 570/570 112 in my boosted 5.3

 

That's what I was looking to hear! is that Isky your running Have a aggressive sound to it or anything?

 

If you plan to use ls7 lifters you have to delete the dod/afm which is highly recommended anyways. On my 03 4.8 all I did was ls7 lifters ls9 gaskets head studs and a set of stock 799 heads with prc .650" dual springs. I used the Vinci turbo cam which is very mild. 216/216 .565/.565 114 Lsa. Made 725rwhp on it so far with out any sign of wear on the engine yet.

 

cam sound can be tuned in or tuned out.....hearing it idle you can tell it has as cam of some sort

 

Yeah I'm gonna delete the AFM/DOD, I may go ahead and run some dual springs too.

What octane fuel is that 4.8 on? Any meth?

 

I run e85 and no meth. I dont like meth because I have seen too many kits fail and take out a motor.

 

Those were my initial plans... I was going to run e85, but there's only one gas station that sells it around here. So Im just gonna stay on 91 and see if I can get to 630ish range. I'm also running meth, but not to squeeze all the hp out, more for IAT/safety.

 

Went and picked up a few ls3 parts from a 2013 Camaro motor, my question is what parts interchange for the AFM/DOD delete I'm doing in my 5.3? I got the lifters, timing cover, timing chain, timing gear, valley cover. I'm assuming I'll be able to use the lifters and valley cover, not sure about anything else?

I also have the crank, oil pan, oil pickup tube, cam, 6 or 7 Pistons and rods, block mains, valve covers, if anyone is interested