Ls swap or not?

[CheemsK1500]

IDK man... The L31 swap can get involved or expensive too, the crossover to EFI with in tank pumps, fuel return lines, custom harnesses and PCM re-flashing is more difficult than most of the physical stuff like motor mounts. I did the L31/4L60E swap because my dad had flipped a bunch of GMT400 trucks in the past few years and he had piles of parts which reduced the cost immensely.

Some general costs associated with the EFI swap (prices are approximate & from 18 months ago)
'87 fuel tanks with internal baffling $141 each
Sending units set up for pumps and return lines $92 for one side & $126 for the other
Carter pumps $46 each
Tank switch valve $67
Fuel lines and associated fittings $180ish (I did all Earls vaporgaurd stuff so can be done cheaper)
O2 sensor bungs for exhaust $8 each

PCM $35 junkyard
Pigtails $20 ebay
Flash $100
Pinout diagram $20

Engine and Transmission harness - no cost except 3 weekends labor for 2 people and a donor harness from a late model.
Injectors, O2 sensors, MAF, TPS, ECT, Ign module, Coil, VSS were all used & free

My L31 short block was $700 (unassembled on craigslist)
Heads free
plugs free
Gaskets $150
Timing set $20
Oil pump $35
Wires, cap & rotor $140

Hoses, belts, accessory brackets, A/C lines & fittings, different alternator, different PS pump, different starter, the "E" transmissions may not be capable of working with your stock speedometer... The list goes on & on.



Do your homework and make your own decision, it's your truck, your money, and your time.

I think LS swaps are cool but there's a lot more involved in swapping to EFI than some assume.

The parts list can get long if you start with a bare engine. When I suggest a L31 swap, I assume people will start with a mostly complete engine/transmission unit or better yet, a wrecked/rusted GMT-400. When things like engine accessories and ECMs are missing, things get expensive quick.

 

[CheemsK1500]

Turbo the oil burner.
Or 12v swap it and turbo that one...

If you're jumping down the Cummins rabbit hole, the elusive 3.9/4BT engine that appeared in bread trucks works quite well in a half-ton truck and can be adapted to many transmissions. You can also cram the heavier and more common 5.9/6BT but a half-ton truck's suspension might not like that...

Also keep in mind, the Cummins requires some fab work like the LS or any other non-factory pattern engine would.

 

[Nasty-LSX]

Its more than worth it!. I play with the big dawgs now. Hard to stay out of the truck also. LOOK!

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and

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I have the full build on my channel!

 

[Camar068]

not gonna read all the posts. Keep it simple.

Do your math/research for the swap. If you do the swap, keep EVERYTHING from the old. If you do the swap, don't alter anything that can't be reversed. Good example....if you ls swap it you'll probably need a tank with baffles in it. Keep the old, and buy a new tank. Keep it easy to swap back if you want in the future to sell or if future family wants it back to original.

Cost a few $100 more, but it's easy to swap back. With wiring, it may not seem easy to hide the old, but can be done. Leave it, tuck it, cover it using existing holes ect.

 

[RecklessWOT]

Edited for time and clarity:

So I've got a 1984 c10 short bed Custom Deluxe.... ...been sitting for years and for the most part unmolested. I have since [molested it some]. It runs and drives great and I wouldn't hesitate to drive it anywhere. With all that being said [I want to m0lest it more, go all the way this time. But I keep] hearing my dad in the back of my head saying "if it's not broke don't fix it"... ...what would you do?

My vote is cast. You know the "right" decision here, that's why you're even asking in the first place.

With that being said, it's your truck do whatever you want, who gives a sh!t what a bunch of dudes on the internet think?

IMO the 6.2 sucks, but like you said it runs fine. Personally I already think if you lowered it and put big wheels on it, now isn't the time to worry about keeping it original. I would have never done any of that myself, but it's up to you and your preferences don't let any of us make choices for you.
You already started down that road- you can either keep molesting it harder, stay where you are, or even go back at this point. Once you LS swap it, the truck will never be the same. Do you want a "classic truck", or some of modernized hotrod thing that has old bodywork? Your choice, your priorities, and only your opinion should influence what you do to your own vehicle.

 

[Camar068]

Edited for time and clarity:

My vote is cast. You know the "right" decision here, that's why you're even asking in the first place.

With that being said, it's your truck do whatever you want, who gives a sh!t what a bunch of dudes on the internet think?

Once you LS swap it, the truck will never be the same.

Not true if you keep old parts and don't m0lest it

 

[custodian]

I'm a mechanic/fabricator by trade so I have the skills for the swap and am able to make all the bracketry I need. I guess my question should have been "is the truck any more valuable or rare because of the options?"

I didn't have to fabricate any brackets when I did the LS swap in the 73. Even programmed my computer.

 

[Nasty-LSX]

I didn't have to fabricate any brackets when I did the LS swap in the 73. Even programmed my computer.

Its awesome when you dont have to pay anyone to do anything for you!! I ended up buy HP TUNERS
and very happy with it.

 

[MikeB]

It has what seems like to me some more unusual options on it. First off it's got the good ole 6.2 diesel and 700r4 drivetrain which is a little unusual for a short bed. It also has factory air, full gauge cluster(possibly because of the diesel engine) and the interior has carpet floors and kick panels. It runs and drives great and I drive it a couple times a week and wouldn't hesitate to drive it anywhere.

That's a combo you will probably never see at any car show. And if it's running fine, keep that engine! I know nothing about diesels, but there must be some tips and tricks that can help it make a little more power.

My only experience with LS engines is rebuilding a 99 LS1 to LS6 specs, but I see and hear about all kinds of problems with LS swaps. And that's after you spend money on motor mounts, fuel tank, pump & lines, accessory drives & brackets, exhaust system, and on and on. At least that was true for a 55 Chevy car, Heck, even my 82's conversion from 250-six/manual trans to 350/TH350 was not trivial and required lots of parts that I hadn't counted on needing. And I had to hunt down a few that are no longer made.

Now, if you have a large budget and can find a reputable shop do the swap, you'll probably be happy. But do your homework on choosing the shop. I know at least one guy on this forum who was burned big-time by a shop, to the tune of several $thousands.

 

[choate]

Hey Mike. Good advice lol. I’m the guy that got burned. If I was to do this again I think I would have went with a 5.3l and had it built to withstand some serious boost (not that hard to do). My truck which is Mikes old one he sold me btw now has a Gen IV 6.0l LS w a sloppy stage 2 cam, high flow intake, long tube headers, built 4l80e trans, posi rear and 3.73s. It’s a lot of fun and drives fantastic but I’m itching for more power already.

 

[Craig Nedrow]

A single Borg Warner 475 T6 will be my LQ4 motivater.

 

[Gmcm78]

I knew i came to the right place for advice. Really got my gears turning now

 

[86 C10 Shortbed]

My 1986 C10 has the crate 5.3L 460hp Jegs motor, 4L60E trans, 3400 stall Circle D converter, and 373 gears. Dynoed at 350hp at the rear wheels, before we had a driveshaft bending issue. The truck is a tire fryer and great on the highway.

 

[Soundmound]

If you're jumping down the Cummins rabbit hole, the elusive 3.9/4BT engine that appeared in bread trucks works quite well in a half-ton truck and can be adapted to many transmissions. You can also cram the heavier and more common 5.9/6BT but a half-ton truck's suspension might not like that...

Also keep in mind, the Cummins requires some fab work like the LS or any other non-factory pattern engine would.

Just in case someone is looking for a 4BT..... y'all should know a lot of the towable compressors landscapers and construction sites use have them in them. Can often be picked up at auction or wrecking yards, probably cheaper than a guy on craigslist who "knows what he got".

 

[JBswth]

While the truck is pretty neat being optioned that way, the truck will be far more valuable with a well done LS swap IMO. I LS swapped my '85 about 3 years ago and have zero regrets, it's so much more enjoyable than a small block could ever be, let alone a gutless 6.2

This one is fairly new, but later on, will not be worth as much as a stock example. I say leave it alone.