I've seen a lot of posts about 6.0 engines out of trucks and vans used instead of the pricier 5.7 liter aluminum block LSX engines out of F bodies an corvettes. I was wondering if anybody has done a swap with the 5.3 liter LSX engine which are plentiful and can be had for under a grand. Is it worth it? I know that it would cost probably the same, if not more, to make the same amount of power that a lightly modified 6.0 or 5.7 LSX engine would make, but 5.3s are easy to come by where I live and the same can't be said for either of the aforementioned engines.

The 5.3's are awesome motors, the one you want to stay away from is the 4.8. Heads, cam, intake all are interchangable between the 5.3, 5.7 and 6.0. I have a buddy who has a 5.3 in an '81 Chevy truck and it runs like a scalded dog. I'm thinking he said he ran 9's in the 1/8th with it. If you really wanted to get fancy, find a 5.3 aluminum motor out of a Trailblazer

Cool. That;s good news. I plan on turboing this eventually too. Anybody know how much boost these things can handle on stock internals? Also, considering this is a GenIII small block, I would assume that a T56 would work, but I figured I'd double check.

i've also considered doing this also..a 5.3..it also seems like they are waaaay plenitiful out here too!.....and klortho u said intakes are interchangeable? as in the LS1 intake will work with a 5.3?..and who knows how big you can make a 5.3 by strokin and borin or either or...sorry to jack the thread :S

what vehicles did the 5.3L come in? and what year range would be best to look at for swapping into an 86 'bird?

thats not that impressive...unless that truck is HUGE but i cant imagine it be that much bigger than my friends 83..which runs 8's with a mild vortec 350

but nonetheless... the 5.3 can be made to run great. swap on a LSx manifold and have the heads ported out with a nice cam and you'll see upwards of 400whp as well, just like the slightly larger 5.7

i'm just not familar with the internals on the 5.3... i know te 5.7 LS1 has been proven to handle some good numbers, especially with upgraded rod bolts

9's on street tires, which for a 4500lb truck isn't bad IMHO.

Internals of the 5.3 are basically the same as the 5.7,6.0, etc. Uses the same block and heads, just with a smaller bore and different crank

well there u go, if you can get 5.3's for cheap, then by all means try one of those out. i might consider one if i cant find a 6.0, but i want to stay all aluminum

they make all aluminum 5.3s. They went into Trailblazers. If you can find a wrecked trailblazer from '99-'06 (?, I forget the last year that this was standard), it'll have aluminum heads and block. From what I see, they go for about 1000 bucks including accessories, ecu and harness.

So the LSx carb intakes will work also?

yes

alot of ppl swap the 5.3 liter heads to ls1's to gain more compression. so any ls1 ls6 intake will work with the 5.3 motor

how big are the stock 5.3 ports? And, would I benefit from swapping aftermarket aluminum heads for 6.0 and 5.7 LSX engines?

i'm not too familar with the specs on those heads but do know they can be cnc'd ported out by several companies to flow upwards of 300cfm, some even more. thats plenty for most motors. the ET Peformance 5.3 head is opened up to a 230cc intake runner and flows 329 at .650"...all for about 1900 bucks... you cant really beat that.

Aftermarket heads are generally good for very large lsx motors needing alot more air, and i believe they have more material to be ported if necessary. they cost alot more tho.. I think the best bargain is to have your stock heads cnc'd out.

Yeah, that'd what I've been thinking. Wow, this project is getting cheaper and cheaper every day...

for the moment i plan on stayin with Gen I smallblocks but really want to upgrade to a big LSX with a 6 speed someday when i get more funds. you really cant beat the performance for the dollar with the LSx motors nowadays

what about adapting transmissions? Say a th350?

More pain than it's worth. The buddy who put the one in a C10 was going to put a TH350 behind it, had to buy a $70 adapter, drill the TB for the kickdown cable and decided against doing all of that and put the 4L60E behind it. So far it's stayed together.

yeah other transmissions will work, but you do need adapters i believe.

5.3's use the same crank. the 4.8 is the only motor of the ls1,2,4, and 6 that uses a different crank

I'm curious, as far as boring goes, if it is a good idea to use the pistons and rods out of stock LS1. People talk about boring to accept forged LSX internals, but considering the price of what that costs, I might as well just go LSX to begin with. The stock internals, I know, aren't as strong as aftermarket forged, but how do people feel about using them anyway?

LS1 stock internals are good up to 450-500hp. A buddy of mine runs 11.10 on the 1/4 squirting all the way down with stock block internals. Valvetrain has been upgraded tho.

I have read that the 5.3 can be bored to make it a 5.7. The 5.3, 5.7, and most 6.0 use the same crank just balanced different for each engines piston rod combo. The 5.7 cranks are drilled through the mains. I am planning on installing a 5.3 I got for cheap in one of my cars. Then upgrading it as I get the money. Mike

What are the 5.3 liter truck engines making at the wheels hp wise? This route seems to be one of the least expensive ways of stepping up to GenIII.

Not for sure about RWHP but they were rated at 300hp (which should be at the crank, like the LS1's 325 at the crank)

Depends on the year.
99 to 02 or 03 was 285 hp.
the newer ones are rated over 300 now.
Badass motor. Powerful and still gets good gas mileage

Did some digging on this over at ls1tech. Here's the thread.

According to that thread, the 5.3 engine in the trucks (between 1999-2003) ranged in HP from 270 to 295.

5.3 is a great engine just as good as any LS series BUT I would only swap one in if I was planning on keeping it pretty much stock so I had a good driver on the cheap. By the time you are done modding one up to the 400 horse range the starting cost difference of a 5.7 vs 5.3 will be minor compared to mod parts. I certainly wouldn't entertain the idea of boring one out etc. just start with a 6.0 and go if 5.3 is not enough for you.

just boost the hell out of it...

Actually thats the best advice yet... My tuner built a 346 LS1 sans F1R and put down.... 897rwhp and its not even fully dialed in yet!! Only mods to the motor ( stock LS6 in 01 Vette ) are forged Wiseco's and Callies rods. Not bad eh?

I have a 5.3 LM7 that I plan to put into a 91 Z28 that I have sitting here. I have the engine complete with computer and all accessories.

AFAIK they'll bolt up to a 700R4 but a 4L60E may be the better way to go. I was looking for an LQ4 but this one showed up. I figure I can swap this one and then if I find the 6.0L engine it'll be easy after I'm at the Gen III engine already.

The LM4 is the aluminum version of the LM7. Info on what came in what is here:
http://en.wikipedia.org/wiki/GM_Vortec_engine

I thought about this but I would only do it if I could have gotten a displacment on demand 5.3. I drive 90 plus miles a day so I would find this combo in a f-body pretty cool. I would think 30 mpg on the hwy and a couple small moddifications would still produce 300-350 hp on tap

I think it would be a good plan to put a T56 behind it, some heads and a cam from Texas Speed and Performance or someone like that. 3.73s or 4.10s in the rear, and you'd have a fun little ride. I thought about a 5.3 in my car for a while, but decided to go with a 6.0 from a truck instead. Not much difference in the price, and alot more upgrade-ability down the road.

Damn, ya'll gave me a good idea!
I was wondering what to do with my Silvy's 5.3 when I do the LS7 swap. Didn't want to trash it.........Got a ton of miles, but omg still kicking hard.

Would that idea be to send the 5.3 to me....

I could do that, but I could also use that in my camaro.
I'll send ya the 305 out of my car, how's that? lol

everyone here should also remember that you can get a 5.3L out of a wrecked pontiac gxp which will have 303hp, alumium heads, displacement on demand for superior gas mileage and still run into the 13's for being a stock motor.

if thats not enough for you then just boost the motor and you'll be in the 11's. (stock 5.3L's respond very well to boost).

I was looking at a newer pickup today and saw it had a aluminum block. so I looked at the sticker and it was a 6.2 lsx type. so is this yet another possiable cheap block to swap in that is even aluminum

Engine Mechanical Specifications (RPO L92 VIN 8)
Application
Specification

Metric
English

General

Engine Type
V8

Displacement
6.2L
376 CID

RPO
L92

VIN
8

Bore
103.241-103.259 mm
4.065-4.065 in

Stroke
92.0 mm
3.622 in

Compression Ratio
10.5:1

Firing Order
1-8-7-2-6-5-4-3

Spark Plug Gap
1.02 mm
0.04 in

If it were a G92 TPI 305...

I want a L92 for my car...I think they are something like 400ish horsepower, aren't they?

I don't know about where you live, but there is a place here that has 5.3 motors starting at $650. And considering you can put a cam, exhaust, and an intake on a 5.3 and be making close to 400hp, you're still WAY under the cost of an LS1 or a 6.0 motor. If you wanted to bore it later, it's nice to know that you can do so, unlike the LS1's which must be sleeved.

And they do respond extremely well to forced induction, due to the compression they run(the truck motors ran lower compression to try to make better gas mileage). The put a turbo with nothing done but injectors on a 4.8 and it went from 285hp, to 542hp with 8psi max boost!! Not that I think a stock motor would last long with that kind of power, but it can be done.

Magnacharger also makes a kit that is pretty nice. If fits in place of the intake, and though it only makes 5psi, it is extremely efficient. A stock LQ4 6.0 motor went from 337hp to 515hp with nothing else. Pretty impressive IMO.

They actually had quite a few aluminum 5.3 motors if you know where to look. They came not only in Trailblazers, but also in Envoys, Bravadas, Rainiers, and the SSR. For the record though, regardless of the block, they all had aluminum heads.

In any case, even if you keep it stock, they dyno at almost 300hp anyway. When you consider that factory L98 motors only had like 230 at the most, that's a pretty darn good jump! And when you look at the fact that an LS1 is at least $3500 on ebay for just a motor, it's not worth the 15-20 horse difference they come with stock.

Valid points but consider internet mania and the huge amount of popularity the LS1 has gained even this year alone I have seen LS1 prices rise. There are limited sources and F bodies are gone a while now hence the ol' supply and demand game. When I bought mine they were abundant and still very affordable. Around here I have found 5.3's as low as 300 bucks and 6.0L for under a grand. Now if you want HP per dollar get a 6.0L and do the L92/aussie intake/cam swap and your talkin over 500 rwhp for under 3000 bucks if you shop wisely. Leaves the 5.3 in the dust for less money than a head cam swap on a 5.3 but I'm sure after another year passes we will see that change too for the next best thing.

Plus keep in mind there is no 5.3 that has usable accessories or brackets for a third gen swap. You'll need a pan, brackets, accessories and be left with a PCM and wiring job with currently less available support although I did see someone added some fresh diagrams and pinouts for truck harnesses on the sticky over at LS1tech.

Never said anything was wrong with a 5.3 just my opinion after doing the swap the the grand or even two difference between the LS1 and 5.3 will literally vaporize if you plan on modding by the time you are done. Only difference will be you'll have less cubes and all all things being equal less power.

I think that for the money that getting a 6.0 is a better idea than a 5.3 because of the larger bore. With the larger bore, you can have larger number of head/cam choices available. Also, you have more cubes with equals more hp per mod.
But, a 5.3 would be an ideal engine for the budget minded daily driver. I wouldn't mind having one (and another 3rd gen).

You both have valid points for sure. I was actually looking into the 6.0 motors, but I can't come up with one of those under $2500 If it was my choice, absolutely the 6.0 motor. More cubes = more power, plus they can hold an insane amount of power w/o alot of prep to the block. I dunno, maybe I'll get lucky and find a good deal on a 6.0, stranger things have happend.

BadBowtie there are far better deals than that available you just have to find them. For instance when I was looking for mine a local wrecking yard here had a long block LS1 from a totaled Camaro and they wanted $3500 bucks for it!!! Insane!!! Thats block, pan, heads, cam, not even an intake let alone everything else.

Recently I found a 6.0L with no accessories but with coils, wiring, PCM for $750.00 so the deals are out there your just going to have to spend some time shopping and searching. Look for a totaled car or truck and buy the whole thing you might do better. Good luck bro