Debating between lq9 or lm7

Sup guys just wanting to know different opinions for my future swap project. I'm debating between a 6.0 or a 5.3. The 6.0 has the obvious displacement + and I think they cost less than a 5.7 ls1. The 5.3 is a lot cheaper and more plentiful. My actual debate is to whether to pick up a 5.3 and bore it to a 5.7, change/bore heads and change cam to where with the 6.0 I would just do a cam and valve train. Looking to get around 350-400hp. Also wanting to mate it with a t56. Any help and guidance would be greatly appreciated.

Kevin

if 350-400 is all you're lookin for I'd say just stick with the 5.3. Mine is cammed and street tuned and I'm pushin 325 to the wheels. I figure a FAST intake, dyno tune and a lil head work would put me in the 350-400 range.

LQ4 or LQ9 would be cheaper than making a 5.3 a 5.7.

i would go with a lq9 or lq4 leaves alot more options open for the future. 408, 414, and you can use l92's

im pretty sure a stock lq9 with a t56 would put you close to your goal, add a few boltons and a cam and youll be good to go, plus youll appreciate the extra torque and displacement, i had a 5.3 t-56 and after a couple months i was bored and wanting a 6.0. just spend it now and save yourself a motor swap and changing parts later.

I would've gone 6.0 but I got a deal on my 5.3. Besides if I went 6.0 there would be pieces of NV3500 everywhere, it should live a little while behind a the 5.3.

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Originally Posted by 99turbogmc

if 350-400 is all you're lookin for I'd say just stick with the 5.3. Mine is cammed and street tuned and I'm pushin 325 to the wheels. I figure a FAST intake, dyno tune and a lil head work would put me in the 350-400 range.

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This what I was leaning towards. To bore a 5.3 to a 5.7 doesn't seem to be worth the work but sure still is an option plus all the extra stuff that would need to be bought to fit the new bore...it adds up. A cam/valve train swap, ls6 intake, rails, injectors and some juice should put me up in my goal range...

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Originally Posted by PitchBlackC3

LQ4 or LQ9 would be cheaper than making a 5.3 a 5.7.

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I'd concider the lq4 but would rather go with the lq9 for the lower compresion and flat top pistons that would be better for boost or spray (plans for the future future). Although the lq4 is cheaper would it be wise to later change the compresion ratio suitable for my application since they both have 317 head correct?

If you're only after 400rwhp, then I'd go with the 5.3L. My 4.8L runs close to 500rwhp, probably over 500rwhp, with a turbo and a few supporting mods. So it wouldn't be difficult at all to make 400+ with a 5.3L.

FWIW, the LQ4 has the lower compression and the LQ9 is the performance version commonly found in the Silverado SS trucks.

if your planning on doing some work and not a "drop in" I'd do a LQ4 with L92 heads, a cam, and a good tune. Magazine articles, for what they're worth, put that combo around 500hp. Also cheaper and less work than turning a 5.3 into a 5.7. Also keeps your compression some what boost friendly. Just my $.02

If I were to go with a 5.3 which one would be best to work with? LM7, LM4, LY5, L33 etc etc as there are a bunch to choose from. Which heads would work best with the app.
Thanks

L33, if you aren't wanting to punch it out. But then again most places want what a LQ4 would cost for the L33.

Okay as I just found out on freight shipping to hawaii is pretty outrageous and the ones I've spoken to on ebay do not ship here. So my best bet is to search here in local yards. I've located a 5.3 but no 6.0 as they are harder to come by at the bone yards. So now things have been narrowed down for me, instead of boring a 5.3 what would be the best set up? I'm planning on getting a ls6 intake, cam for spray, but what would the best heads be? I've heard l92 or ls6 ported were they way to go but just open to others opinions.
Thanks

l92's wont fit 5.3's get 243 or 799's there the same head.

what do you have right now? The L92's will out flow the 243's. You would need a rectangular port intake manifold, and yes they wont fit on the 5.3. L92's also have bigger combustion chambers so it depends on if you wanna stay n/a or ever plan on some boost.

What would be a decent set up for the LQ9? Just wanting input vs on what I plan since wife approved to just get it shipped and get it over with.
-FAST intake
-cam (spec unsure yet but any advice would help)
-heads either milled and resurfaced or aftermarket l92
Being this, what would i be looking at to the wheels?

I'd go with the L92 heads. Make sure the intake you order is for whatever style head you decide to go with. Do a quick google search for "lq9 with l92 heads". There's been quite a few magazine write ups on that set up. They also usually list cam specs. Your exact cam specs will depend on your final setup and your intended usage i.e. daily driver, towing, race only, street strip. Oh and by the way, congrats on getting the wife's approval

Thanks, I'll look into it

LQ9 with milled 243's and a edelbrock proflow intake or a FAST intake. Mill the heads .030 and get a mid 23x duration cam. It will get you 500rwhp and be very streetable...

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Originally Posted by DBRODS

LQ9 with milled 243's and a edelbrock proflow intake or a FAST intake. Mill the heads .030 and get a mid 23x duration cam. It will get you 500rwhp and be very streetable...

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the exact motor im building now minus the FAST/ proflow i wasnt planning on it making 500 rwhp though thats some darn good numbers. what size stall would you reccomend? 3600+?