122sschevy

Iam buying a ls1 engine block and heads from a 2002 corvette and have a 5.3 silverado would I be able to use any thing with my truck or is it best to just build the ls1????? Cuz if I can make my truck have more hp with the ls1 I would rather do that?????

Burken01

iTrader: (88)

It would not be cost effective to swap in a 5.7 ls1 block just to gain a few more hp..

The parts and labor to do it would be better spent on maxing out the 5.3 engine you already have..

Save the money and buy a nice head/cam kit for the 5.3 engine..

122sschevy

Ok so which head do u suggest

Burken01

iTrader: (88)

A good budget head setup would be some 243's

Texas speed has a lot of options on their website, and are priced reasonable.

It comes down to how much money you want to spend.

Do some searching on head/cam 5.3 combos and see which route you like..

96capricemgr

iTrader: (1)

A Vette LS1 likely commands a huge premium for basically nothing all that worthwhile, that would be about the last road I would take if modding a truck.

Far as what to do that would be good what boltons does the truck have?

122sschevy

Headers cai tbs

96capricemgr

iTrader: (1)

My understanding is that on the trucks a CAI is about noise not performance and even headers aren't all that worthwhile till you go inside the engine. If by tbs you mean throttle body I would probably scratch that idea too, I have it from a good source that the 07+ new style intake with larger TB is worth a whopping 6fwhp on a stock 5.3l that is intake and TB together. So the intake and TB together might be worth swapping to the later ones if you are going to mad the engine but to just put a TB on what you have seems like there would be a lot less potential for gain.

The 2002 Vette I believe would have come with an LS6 intake which is I think 3hp up on the 07 and earlier truck intake, seen some reports that over 5500rpm the LS6 keeps pulling better where the truck intake drops off but point is the truck stuff is pretty good and I wonder if the later truck intake might be just as good as the LS6.

People want to poopoo truck engines without bothering to understand whay the different power outputs.
Not normally a fan of magazine "data" but so long as they aren't selling anything for a sponsor and are just comparing stock parts they can be useful.
http://www.carcraft.com/techarticles...st_comparison/ Keep in mind this is flywheel without accessories/intake or exhaust systems so the gross numbers are higher than GM ratings.
The LS1 cam alone is worth 29hp at 300rpm higher than the early truck cam combined that with the higher octane tuning the cars got and you have accounted for the majority of the HP difference between the motors. On the 5.3l though the LS1 cam did hurt lowend.

Point being why pay a premium for a likely used hard car motor when there are fairly substantial gain in understanding what is holding your current motor back?

Put an LQ9 cam in it and an custom higher octane tuning, flip the LS motor and put the cash saved into other mods, like stall or gears.

Remnant-of-VII

Yeah, but think about this. For most of the 5.3s out there, they're rated @ only 285-300hp while the Corvette's ls1 is @ what, 330-340hp. It's easier to hit 400+hp N/A with a mild cam on the ls1 than the 5.3.

I'm not knocking the 5.3. It's a fine little motor that's cheap and reliable. The ls1 just has more power potential in the long run. (Not to mention it's 80lbs lighter.)

Sell the 5.3, get rid of the throttle body spacer and use the money to fund the ls1 mods.

96capricemgr

iTrader: (1)

The Vette LS1 is rated higher with a fair bit more cam and 91 octane tuning. You are ignoring what accounts for the HP difference.

Yes the LS1 may endup with higher power potential, and a lot more potential for block problems. The LS1 will command a premium price that could be better spent elsewhere.

Far as weight, who give a crap in a truck,things are so porky anyway.

IMO the OP could get stock LS1 performance for less money with a thoughtful cam selection, NOT an LS1 cam as I think GM deliberately limited lowend on the f-bodies with their crap axle and some boltons.

I guess you do kind o raise a valid question though about how far does the OP want to go? Do you want a modest bump in power to make the truck a little more fun or are you going to chase some real power? If chasing real power then yeah I would probably opt for some displacement increase just to make the power easier to achieve while retaining lowend for the truck. If you want "stock LS1 power" then a stock LS1 would not be the way to go, some mild mods and boltons to the 5.3l will serve you better.

RezinTexas

For a truck application, I would get a 6.0 motor for much less than the LS1 and have more power potential with heads/cam modding.