Is 5.3 swap to much money and work?

[72LB]

Funny to see this thread. With my 69 I am at the point that it's time to replace the wore out 350. I have considered a LS swap and did do the research however with what I have to change and price another 350 will be going back in. I will say what has already been said it does depend on what you want from your truck.

I can say personally I like the good ole sbc. I have seen many LS swapped trucks and only a handful have I really liked as they were done looking more like the engine that was in it originally.

[webfoot]

Originally Posted by trac209

Many guys who have gone the LS route toute mileage as the best advantage and really if you ask me that’s where the advantage ends,even then it’s marginal when you can buy a stand alone Efi and get in that range easy. Friend of a friend has a 383 making an easy 550hp with a 5 spd and a efi and he gets 20 plus mpg all day long. To each there own,personally I find the LS swap the world fad to be getting out of hand.

That is pretty solid evidence right there, I'm gonna sell my LM7 tomorrow.

[trac209]

Originally Posted by webfoot

That is pretty solid evidence right there, I'm gonna sell my LM7 tomorrow.

Nobody is trying to convince you of anything,what I’m saying is the LS isn’t something everyone wants or needs. Seen enough LS swaps to know they are the real deal when you want to build a junkyard engine with a eBay turbo and click off some 9 second et. Not everyone cares about that though. And an Sbc can do it all day long as well if you’re willing to build it.

[rjs53]

Originally Posted by webfoot

That is pretty solid evidence right there, I'm gonna sell my LM7 tomorrow.

You know I'm always the last one on a bus, but I still want on. I'll take the LM7 off your hands, dirt cheap that is cause its overdone, and let you get back to your roots. Just being a smart a.. don't mind me

[NJRC10]

I have since sold my bronze/white 72 that had a bad engine ( kept it and it has since been rebuilt and installed back in the 72 ) and found a used zz3/700r4 to replace the 350/350 which made the truck much better to drive. My 1985 gmc had a 305/700r4 and a buddy of mine and myself finished a 5.7 ls1/4l60e used of course, which which was twice the cost and then some of the 72 swap. However, it is a night and day difference in drivability, twist the key and it fires right up and it runs as smooth as butter!! But once you go ls and do a really nice install job, I have found there is never a reason to have an old school carburetor again. ��

[weq92f]

Originally Posted by NJRC10

...it is a night and day difference in drivability, twist the key and it fires right up and it runs as smooth as butter!! But once you go ls and do a really nice install job, I have found there is never a reason to have an old school carburetor again. ��

Once you successfully go EFI over carburetor on any engine, you'll likely find you don't want to go back just the same, no LS needed.

With these systems available today, even old school hardware can be brought to the level of "twist the key and it fires right up and it runs as smooth as butter!!"

-klb

[Slowguy]

I had a time deciding which route to go also. I knew when I saw the thread title this was going to be a hot topic that I think has been debated 100 times before. It seems like it’s one of those questions when people ask what’s better, Ford or Chevy, etc. Each obviously has pros and cons.

I still have the old 327 out back and it’s original to the truck. I’ll probably rebuild it just for fun once I have the truck on the road with the ls in it. I know very little about both engines as all this stuff is new to me but engine tech is not. I have a little knowledge mechanically and a pretty good eye for detail.

I chose the ls because I got the entire truck for a fair deal, and that gave me a complete platform for a donor. I wanted the beauty of the original truck (one of the best looking pickups ever imo) and the convenience of the newer power plant. In addition to that, because LS Swaps are so common, there are a TON of suppliers for swap parts, conversion kits, etc. Also, threads and knowledge abound about the engine itself.

If you want the engine pretty, there are plenty of options there also. I see some they make look more like an older engine, relocated the coils, add vintage looking valve covers and more. Really, it seems the options are limitless. Just depends how much you want to spend. On the other side of the spectrum, you can usually grab a 150k mile engine, do nothing to it, swap it in and go for another 100k. I’ve read plenty of those stories also.

Another reason I went with the ls is I can have all the power I want. Slap a turbo kit on and make a minimum of 550 whp on minimal boost. I’ve read the stock junkyard engine has been proven to handle 700 hp in stock form. I decided to do the heads, complete engine rebuild, gap the rings, upgraded valve springs, valve seals, engine cam, cam chain tensioner, new bearings, polished crank, new push rods, new rings, bead hone cylinders, melling oil pump, Siemens injectors, arp rod bolts, arp head bolts, and I think it cost me about 1500. Not bad, I thought.

I went a bit overboard just because I usually do, but I know what’s in there and it’s absolutely spotless. It’s not for everyone but I wanted something just a touch more flashy than Chevy orange. I like how it looks so far. I think it will look pretty nice in the cleaned-up engine bay.

[Wikid61]

Originally Posted by Coley

A nice 350 small block, stroked to 383 with a kit, a professionally built Quadrajet, a reasonable cam for a heavy vehicle (NOT long duration), new electronic ignition, a new/quality dual plane intake manifold and professional dual exhaust.....and your golden.
You will light up your tires at will, idle great, accelerate like hell, you can detail the heck out of it custom or leave it completely stock appearing.

Ba-da-bing.

All good
Coley

Amen. I have done this w/'76 350 smog motor turned into 383. Custom Clay Smith cam, mid length headers, 882 heads shaved & opened to 2.02 decked for 10:1 compression, Balanced, assembled, broke in, out the door $3K. My dream motor is a 348 stroked & bored for 440 cubes & those valve covers? In a '60's GM truck? Priceless.

[MARKDTN]

Originally Posted by weq92f

Once you successfully go EFI over carburetor on any engine, you'll likely find you don't want to go back just the same, no LS needed.

With these systems available today, even old school hardware can be brought to the level of "twist the key and it fires right up and it runs as smooth as butter!!"

-klb

Absolutely! Carburetors are no fun, especially with todays fuels that eat them up. If you like a Gen 1 350 then a fuel injection conversion makes them so much easier to deal with. A TPI swap on a stock bottom end will really wake up a lazy 350. Lots of low end, and the TPI is the best looking induction system Chevy has ever made IMHO. For serious power you have to have improved runners and do some porting. There are other turn-key FI systems also. I like the stock GM systems because they are very reliable and parts can be bought in any parts store-or junkyard- in the country.

But to the OP question again. If you don't have an engine LS is almost a no brainer. If you want to show it and care what the engine looks like, maybe old school is better-maybe. But I happen to like the way an LS looks over an orange carbed small (or big) block. But if you want to drive it, if you want mileage, if you want reliability; then an LS swap is a great way to do that. Dollar for dollar you will be hard pressed to beat an LS swap for power. A complete bone stock small block rebuild done right will be $2500 or better with doing the heads right and build the carb etc. You can buy the LS engine AND transmission for less than that. A performance build can easily double that. But, there is no universal wrong or right answer. You have to figure out what is right for you.

[bhayes1]

What about the benefits after the swap? Once you get all the auxiliaries taken care of such as fuel tank, fuel pump, exhaust, motor mounts, ECM, etc. done right you shouldn’t have to mess with them. So let’s say you wear out your gen1 sbc...likely you will replace it with an L31 costing around 2k just for the long block. If you need to replace an LS in a truck that is already set up for it you go to the junk yard and put in another 100k mile 5.3. Just thinking about the looong game.
Posted via Mobile Device

[palallin]

Originally Posted by weq92f

Once you successfully go EFI over carburetor on any engine, you'll likely find you don't want to go back just the same, no LS needed.

With these systems available today, even old school hardware can be brought to the level of "twist the key and it fires right up and it runs as smooth as butter!!"

-klb

However, "twist the key and it fires right up and it runs as smooth as butter!!" describes my 327, for all intents and purposes. Only when I let it sit for a while does it take more than a revolution or so to fire, and it runs smoother than my wife's 5.3.

Each to his own, boys, but my engine does everything I have ever asked of it, and its failures have been a question of service parts.

[palallin]

Originally Posted by MARKDTN

A complete bone stock small block rebuild done right will be $2500 or better with doing the heads right and build the carb etc. You can buy the LS engine AND transmission for less than that.

A mystery engine/tranny out of a junkyard, maybe, but not a fresh set ready to go.

[MARKDTN]

Originally Posted by palallin

A mystery engine/tranny out of a junkyard, maybe, but not a fresh set ready to go.

Quick Ebay search found several 5.3/4L60E for under $2000 with trans, computer, all accessories. 160K or so miles. Most guaranteed 6 months. Several without trans for around $1200. You can go mystery at Pick-a-part for way less, but I'm talking running pullouts with warranty. If I dig I can find less miles or less money. These 5.3s will go 300k easily. So for a weekend machine I would have no problems with this.

You can buy a new basic crate 350 for less than you can rebuild it-if you do it right. And have better heads and less leaky.

Again, I'm not against gen 1 small-blocks. I have 2 running. But the OP question is an LS swap worth it, I say yes.

[Signkutter]

I did an LQ9 6.0 swap from a slightly cammed and fuel injected 350 with 60909 Edelbrock heads. The Edelbrock EZ Street fuel injection was a nightmare and never ran right...so no good example to compare performance from.....but the swap did produce a very smooth running truck with plenty of power from a rock-solid stock engine....(and a $4k paperweight unless I can sell the heads and cam\intake)

I paid about $2.5k for the swap with all the necessary hardware and tune, and $1800 for the motor with 74k on the clock

[Slowguy]

Originally Posted by webfoot

Lots harder to find now as those were only put in the 4th gen camaros & FB plus corvette through 04 as opposed to millions of LM7 (5.3L) blocks.

Nice looking build Slowguy!

I have a mid-mileage 99 5.7 sitting out back I'll be pulling when the weather's better. Don't know what I'll do with it but an employee smashed the van so I have yet another engine to add to the collection that I have nothing to do with!

[62bagger]

I have been following this thread and I think LS or gen 1 depends on preference. I have seen some really nice engine compartments for both. I was thinking I would go with a gen1 on my build just because I am not sure if I could figure out how to get an LS connected up. I have heard the wiring can be complicated. It might be a good option for me dollar wise since I need a motor and all the manifolds, alternator, accessory drives,etc. I can get an LS with everything at a reasonable price. How easy is it to get the harness connected?

[57taskforce]

Originally Posted by 62bagger

I have been following this thread and I think LS or gen 1 depends on preference. I have seen some really nice engine compartments for both. I was thinking I would go with a gen1 on my build just because I am not sure if I could figure out how to get an LS connected up. I have heard the wiring can be complicated. It might be a good option for me dollar wise since I need a motor and all the manifolds, alternator, accessory drives,etc. I can get an LS with everything at a reasonable price. How easy is it to get the harness connected?

It’s mostly plug and play if you buy a pre made harness. I modified my own for the 6.0 swap that’s going in my 72 K20. Modding your own is a little more complex and time consuming but not bad. Normally they are setup so all they need is key hot, constant hot, and ground. You’ll also have to wire in anything that you’ve decided to have computer controlled like the fuel pump, cooling fans, etc. (those things are mostly all optional depending on what your doing with your build) Then you have to hook all the sensors up, route your harness, and mount the computer.

[62bagger]

Thanks for the info. That does not sound as bad as I was expecting. That gives me something to consider.

[HSRACER]

I have a combination of old school small blocks and LS engines. Each has its place but after driving with LS power that’s all I am doing in future builds or replacement stuff.

They work so good and the driving experience is awesome.

Here are a few pictures for you to see what I have in my trucks.

[dmw319]

Originally Posted by webfoot

Lots harder to find now as those were only put in the 4th gen camaros & FB plus corvette through 04 as opposed to millions of LM7 (5.3L) blocks.

Nice looking build Slowguy!

Not hard to find around here, at least.. and for decent prices!

[Kudzupatch]

FWIW I went through this and there is no right answer, best answer is it depends.

I have a very nice 93 Suburban so I have TBI. 230K on the engine and still runs great. Uses about a quart every 3K miles. If it were not or the rod knock before oil pressure builds I wouldn't do anything.

I looked at all the options. LS is interesting and i would like to do the swap. But since I want to tow with it I didn't want to go smaller so I really wanted to 6.0.

Installation is much more work, a lot more work. All the adapting and wiring. Then as a buddy who has done 3 conversions pointed out they can nickel and dime you death. All the little things you don't foresee. When I totalled up the cost and even going low on the unexpected it came out to 3,000-3,500 if no major surprises. That is a used engine I know nothing about.

I can buy the L31 engine which comes with roller cam, one piece rear main and it is a new engine, not rebuilt and with a warranty for $1,800. Install is so much easier. I want to keep the TBI so there is a little extra work there. But all the accessories, wiring, ect work. So labor is much less.

Weighting the cost, extra work and it just didn't make sense. Sure it is cool to have an LS but I just don't see the gain being anywhere near worth the extra effort and cost for me.

[derotoreut]

There is no right or wrong answer here. I was torn with making the same decision. It all depends on what you plan to do with your truck and if going LS makes sense for your use. You could justify it either way. The bottom line is what YOU want to do.

I have a friend with a 64 Chevelle who was kicking around the idea of doing a LS swap. In the end he said it just didn't make sense for him. His car has an older Edelbrock crate engine, but it's dialed in so nice and runs great. Why would he want to change it? His case may not be like others, since his engine is running so strong it doesn't make sense.

Good luck with your decision.