How much power can these alum 5.3 blocks handle on the nnbs?

[TvsQuez]

I have an 07 nnbs, and right now i have the s/c, cam, headers, tuned so far. I dyno'd last time at 480rwhp. My question is this. I've been looking at new heads, meth kit, and a shot of nitrous. Can these 5.3's handle it? I'd like a strong 500rwhp truck. Strong on the street. I have a built 70e tranny, i have true trac, i have gears, servo, shift kit, and yank 3000. I'm just looking to see if I can do more work to it, and the block be ok? any suggestions? or opinions on the durability of this thing? Yes, i've had the option of going to an lq9, but I want that outta question for now. I'd like to work with what I have. I don't have the money to be adding all this stuff on for the 6.0 swap. THanks again.

[oleshifty]

honestly...if you only want 500 horse, a set of heads should bring you there. If you want more, why not just put a smaller pulley on the s/c? I don't see point in blower AND nitrous, but that's just me. You can either get lower compression heads and more boost, lose a little bit of streetability, or keep compression higher, and run less boost, to make it more streetable.

[TvsQuez]

I have that rousch supercharger is why I haven't pulley'd down. I'd have to re-key it etc...I was looking at adding meth, but i really want the truck to be a very strong street truck. If I could push more then 8-9lbs of boost, and maybe a 75 shot? Would that be pretty dangerous to the motor? I was looking at new heads, meth, and cutouts. Just haven't really seen many with doing up their 5.3's. Most jumpt to the 6.0. Thanks for the reply.

[rutroe]

I HAD a 5.3 with a T-76 turbo @ 10 psi and 75 shot of juice. Dynoed around 480 at the wheels. My #7 let go not long after the additions (search for #7 issues on this site to see how frequent it is). I had a 6.0 installed and haven't had a problem with the power yet. The tranny (a built 65E) is another story. Looking to do the 80E swap when I get the chance.

[Frenchy]

Garrison's (LamboDoNoMoHomoRopeSucker) putting likely 550+ to an aluminum 5.3

[RUFFNECK]

I've heard 500 is the threshold for the bottom end.

[pl4yboy]

Then how did George push nearly 800 rwhp to his 4.8 for years?

[kyhunter89]

He says its because of a perfect tune

[pl4yboy]

Either way, he did it and it's a stock block 4.8... Although, it wasn't aluminum.

[George C]

the number 7 shit is bullshit. a motor fails cause it was mistreated or improperly handled. a 5.3 should easily make 800 rwhp without a hiccup if in the right hands and given proper support. Like cool IATs, cool ECT, good tune, smart driver, good tune.

also to get 500 hp i wouldnt consider 2 power adders for such a low hp level goal. 500 is roughly 9-11 psi. two power adders is just an excuse for the lack of another. Plus its more complications especially for such a goal as of 500.

i think ducky has been unhurt for several years at 500ish with his 5.3, trevor1 has well over 600 on a 5.3 for many years now, im sure theres others but those are just to name a few