454 vs 5.3 LS swap 1 ton Crew Cab 4wd opinions

[dylanr1]

Hi all, been a long while since Iv logged on here, sorry for being away lol.. okay so like the title says, my 6.2 diesel has finally let me down (head gaskets). I picked up a complete LM7 5.3 with 130k on the cheap as winter project.
Well, since the headgasket issue on the 6.2, I’m debating what to replace it with, and believe me, Iv exhausted the research on here and other sites so much I decided I need outside opinions. I can get a low mile GenV 454 (tbi) for under 500 bucks..I know theyre the least desirable gen but Iv had one previously and have no real qualms about them, despite their shortcomings they’re reliable and easy to work on. My goals are: Enough power to make such a heavy truck half fun to drive, reliability, not spend a fortune. Mpg is of no real concern, this truck only gets driven here and there during warmer weather. So, 5.3/cam/springs/holley terminator x/China turbo or BBC/cam/springs/rpm airgap/aftermarket efi?
Posted via Mobile Device

[Blue82Chev]

If it were me, I'd build up the 454.

Change out the pistons for some with higher compression (Pretty sure factory was 8:1 on those)
Toss some better heads on it
Cam
Sniper EFI

You'd have yourself a nice runner for probably less than an ls swap. Those ls swaps can nickel and dime a guy to death.

[bnorth]

Big heavy truck I think you'd enjoy the torquey BB more than the LS.

[theastronaut]

A 5.3 lacks the torque needed to move a heavy truck, you'd need 4.56 or numerically higher gears to get the rpm up in the range where it makes power. I swapped one into a '51 GMC that had 3.73 gears and it was just ok. We have one in a 2010 Tahoe and it sucks when empty, and struggles to pull a trailer. I wouldn't consider an LS swap in a truck unless its a 6.0 or 6.2.

Our '79 C30 with a mildly built truck 454 (peanut port heads) and NV4500 will spin the tires in second just rolling into it and pulls a trailer really well. Look up Richard Holdener on youtube, he has a lot of dyno tests with junkyard 454s to get an idea of what can be done with one easily and inexpensively.