Why do I want an LS motor?
 

So I originally wanted to make the '79 a modified stock truck. Biggest things were a carbed 350/sm465/np205/203 on 4"s and 35"s so I could take it wheeling...

And then I put a big dent in the side of the truck and I decided I dont want to beat on this one. SO,...

My friends have been saying 5.3 this 5.3 that, and at first I was like no but now I'm really starting to think about it.

IF I do decide to go with the 5.3, Do I want to go carbureted or fuel injected? Keep the th350 and np203 tcase? also I want to keep everything on the interior stock looking so you cant tell its been swapped.


I would like to hear all opinions and advice on this. Lets say I'm on a budget of roughly 2k... I can get the stock motor/harness/computer for around 5-800 bucks. I'm not cutting corners either.


If my budget is too low for your opinion say it anyway. I can always wait a little longer and factor that difference in.

Thanks.

Re: Why do I want an LS motor?
 

Cheapest way is to keep your trans and transfer case, find a 5.3 with all sensors that doesn't need a rebuild, and do all the work yourself. You'll need a tune to tell the computer to ignore that it can't see the transmission sensors... for hard parts you'll need motor mount adapter plates and possibly a flexplate... Some incidentals along the way for sure, but I could get it done for less than 2 grand for a bare bones job. But to me, bare bones job is cutting corners. I wouldn't go through all of that for a stock 5.3... I'd be all cam/headers/heads/intake manifold/throttle body/etc.

Re: Why do I want an LS motor?
 

Spend your cash on a great set of heads for the engine you have, that is where all the power is and one of the main benefits of an LS - along with their thin metric rings, a roller cam, and high ratio rocker arms. You can install these into a conventional sbc gen 1 block too.
Then you can blow past the 5.3 and 5.7 LS swap engines that cost a lot more.

The 6.0 was to replace the old 454, but they still had to release the 8.1 for torque needs.
Don't get me wrong they're great engines , I have a little 4.8 in my 1 ton box van, but it has 4.10 gears and wouldn't be able to tow anything - unless I emptied what we always carry.

Trucks love torque and that's what I'd have in mind vs. HP.

Re: Why do I want an LS motor?
 

Go with the LS, more efficient, more potential and longevity. LS cost a little more to build but knowing what I know now! Best bet is to convert to cable driven And do a complete swap

Re: Why do I want an LS motor?
 

On ebay for a 5.3l 4l60e computer/box and harness it's $1200 shipped. With a 6 month warranty and guaranteed to run. I'm going to give it a few nights before I make a decision.

I originally bought the truck because it was all mechanical and simple to work on compared to newer vehicles. And now I'm considering throwing a computer controlled motor in it... it's amazing what happens in 7 months lol

Re: Why do I want an LS motor?
 

Give me a 70 LS-6 any day.

Re: Why do I want an LS motor?
 

Look at it like this better gas mileage easier to start and smoother idle.And the ls family can make some big power pretty easy now if you got the cash.

Re: Why do I want an LS motor?
 

I have the 5.3 in my 99 Z71, I really like the way it runs.... It has plenty of power and I'm not racing it. It does not hesitate to pass someone... I really like the way it runs... And it has 250k and runs like it's brand new.... Has only had SYNTHETIC OIL in it....these motors are built to last.... When it comes time for my 87, I'm thinking about looking for a 5.3

Re: Why do I want an LS motor?
 

If you go LS, keep the fuel injection. The fuel injection is what makes it all worth it, in my opinion. I did my 5.3 swap for $2k and have seen people do it for a lot cheaper than that. Just do your research. I used my stock th400 and transfer case as well, works good. Also, my interior is completely stock, even the gage cluster. I was getting 7 mpg with my old 3/4 ton, TBI motor, 4.10 gears, and 33 inch tires. Now with the 5.3 I got that up to 14-15 mpg. If I put an overdrive trans in it I would expect it to be even better. So everything you want is possible.
Personally, I think LS swaps will date your car because there is much bigger and better technology coming out all the time. But they are SUCH great motors for a great price with tons of aftermarket support for easy modding.
I'm in the middle of another LS swap right now. You're welcome to check out my build threads linked in my sig, but there are a ton of threads on here with a lot more info.

Re: Why do I want an LS motor?
 

And one more thing to mention, LS swaps are easy. A lot of people go carbed because they don't think they understand the computer and fuel injection. But I'm just a kid in my early twenty's who has never taken an automotive class in my life. So if I was able to do it with good results, anybody can.

Re: Why do I want an LS motor?
 

If you go 5.3 or any Gen III small block, go with the injection. The cost to run the MSD box for the ignition system and the intake, you could have bought a custom harness and controller for the injection. Then you are still dealing with carb issues for tuning and driveability. Add to that the fact that you would still have to put an electric fuel pump on it since the Gen III's never had a mechanical fuel pump on them.

The Gen III's will give more power and better fuel economy over a first gen small block, stock vs stock. Once you start hopping them up, the gap widens.

I'm in the midst of collecting parts for my 5.3 swap. Savvy shopping has netted some bargains. I've got a list of stuff still yet to get, but I'll spend money on new stuff that I need and save on some of the other parts by getting used from a boneyard (brackets, fan/clutch and stuff). Half the fun is the search. Once I've got the parts list together, it's going to DirtyLarry's for the procedure. Doc Larry is going to lend is shop space and expertise to do a clean job.

Re: Why do I want an LS motor?
 

I had one. Awesome motor in it's day but the newer ls motors would chew it up and spit it out!
If you're considering an ls swap just listen to this 700 horse one on roadkill.

Re: Why do I want an LS motor?
 

I checked yours out before I made this post and I'm glad you commented. I've read all these replies a dozen times today and I think I'm going to make the jump. The only thing holding me back is I like the look of old skool motors better than today's motors. At the same time I like the performance newer motors have.

I feel like I'm going to the dark side.

Re: Why do I want an LS motor?
 

I'm sure there's a LOT of hot rodders out there that won't like the swap (not that I care). I just don't want to be looked down upon when I roll up to a show and pop my hood lol. I was introduced into hot rodding by a very "numbers matching, original everything, period correct" individual at an early age and it kind of took root.

Re: Why do I want an LS motor?
 

I'm totally new to this and tired of my 350 v8 gas guzzler piece of crap.How much hp and rwp this engine put out.Im not planning on 4x4 but I do plan on towing quit a bit around 1500 pounds 2000 pounds maybe small boat etc.

Re: Why do I want an LS motor?
 

i would want an overdrive trans over the ls engine by itself to th350. the combo of a ls and od trans is best.

Re: Why do I want an LS motor?
 

you do know the last 8.1 was built in 2005 and the 6.0 only made 15 ft lbs less tq than the last mpfi 454. i had a 4wd 4.8 truck with 373 rear. i pulled cars with it at 65 mph on the interstate all the time.

Re: Why do I want an LS motor?
 

4.8 is around 270-285 depending on years. 5.3 is around 285-330. 5.7 350. 6.0 345-400. 6.2 is 415ish. 7.0 500 good luck affording the last one though.

Re: Why do I want an LS motor?
 

+1 I agree with this guy.

Re: Why do I want an LS motor?
 

There are lots of ways to doll up these LS motors and I think they can look great.


Join us.. Join the dark side

Re: Why do I want an LS motor?
 

move the coils and clean up the intake they look as good as other engine really.

Re: Why do I want an LS motor?
 

Lol. Eventually I would put the OD transmission in. What I'll end up doing is driving it for a little with the TH350 and then once I have the $$$ finish swapping the OD trans in.

That'll be after regearing though.

Re: Why do I want an LS motor?
 

its easier to go ahead to swap trans at the same time you have ecm harness and all that already to run it. just get a 5.3 4l60e out of a junk 4wd. make sure to get the 4 to 6 bolt transfercase adapter from the newer truck while your at it. with the long shaft 350 or 700r its a direct bolt in.

Re: Why do I want an LS motor?
 

How does the linkage for the th350 differ from the 4l60e? The only thing is about putting in the tranny ill have to adjust driveline lengths which takes a little more money aka time.

The goal is to have it done by June.

Re: Why do I want an LS motor?
 

you can use the same shift linkage you need to change the indicator in the dash but thats 2 screws. the rest is computer controlled. you need a vss signal from your transfer case(with both trans for the ls). pretty simple just buy one of the signal generators. iirc the driveshafts are the same(i think). gm used a different adapter on the th350s vs the 700r4 so if you use the adapter off 93 up 4l60e truck and bolt it to your transfercase and the ds should work. if not your rear would be long enought to cut down and all you would need is the longer one off any od truck/suv for your front. your truck has the np208 right? you need to move the crossmember back but if you can use a drill this shouldnt be a problem. in a 700r4 truck the 4l60e is a bolt in which started in the early 80s. so if you had to source parts shouldnt be hard at all.

Re: Why do I want an LS motor?
 

if you have the np205 then its a little harder and im not as keen on them but i think you just get the adapter and shorten lengthen the ds. if you could find a ome od truck though you can get the 208 and ds from it direct bolt up.

Re: Why do I want an LS motor?
 

I kept my th400 for the exact same reason you stated. I plan on putting an OD trans in when funds allow and I want to drive the thing NOW. lol.
Also, I'm planning on doing a 4l80e instead of the 4l60e. My PCM will need to be tuned for the 4l80e and the cross member will need to be moved back. Cool thing about the 4l80e is it will bolt directly to the old transfer case and you don't need any special adapter.
And about the VSS, I bought mine from dakotadigital and it lets me use my stock speedo gage with cable.

Re: Why do I want an LS motor?
 

to not swap while you do the engine id double the work is what im getting at. you can have the engine bolted to the trans and stick it all in at once alot easier. the 4l60e is direct bolt for the np208 the 4 to 6 adapter is included in new trucks from the factory. so when you getting the 4wd tranny just grab that with it. the np205 idk for sure but the adapter may work on it too.

Re: Why do I want an LS motor?
 

I've got the np203. I haven't made the decision yet about the 208. When I do put the 4l60e in I'll most likely go with a 208. I want to do the swap without having do modify the drive shafts first and then finish up later with the transmission swap.


Heck if there is a deal going on I might end up going with a SM465.

Re: Why do I want an LS motor?
 

I'll tell you what I did on my nephew's truck.

5.3/4L60E/ NP241 from a 91 Sub. ( VSS built in ) Used a 91 Sub/Blazer dash cluster that has the elec speedo already. Looks stock ( not 73-80 stock but close )

I was able to find a rear drive shaft that would work, but he had to shorten the front. The NP208/241 Linkage is the same for what thats worth.

If you want to run OD some day, I would do it all at once, one and done. But that is just me, there is something to be said for doing just the enigne, your going to see improved mpg, and more Smiles Per Gallon over the engine you have now.

Nephew's truck sits on 35's 4" of lift and he see's 16-17 just running around. It made it a nice truck. And its actually a pretty quick truck with the 4.10's in it.

Re: Why do I want an LS motor?
 

i would get a 5 speed over that sm456 .nv3500 from a 4.8 bolts right up to a 5.3. you should just be able to find a junk 80s truck/suv and either get the 208 or the 241 like bowtie said and the front driveshaft too. cutting a ds is not alot of work its when there to short is the problem. its going to be easier to do it all at once like i was saying. im sure you could find a 208 and the drive shaft for a 150 bucks.

Re: Why do I want an LS motor?
 

Interesting how much gas mileage would something like the 6.0 put out and 5.7.I wonder how much those cost and would people recommend these ls for towing.

Re: Why do I want an LS motor?
 

I did an LS swap on my 94 K1500. I use it as my work truck. Tows great, improved MPG. And will walk any newer truck from a light :D

Re: Why do I want an LS motor?
 

Your right. I have a daily so it shouldn't be a big problem to let this sit. I might end up getting this done sooner than expected.

Re: Why do I want an LS motor?
 

it all depends on what your towing and what trans. all are capable of the mid teens. i had a 01 4wd 4.8 truck i would pull 6-7k behind it all the time it would get about 15 mpg when hooked to the trailer. when unloaded i saw up around 23-24 mpg once on the highway. could avg around 20 mpg. in a half ton the 4.8 or 5.3 would be what i would want. now with a hd truck id def want the 6.0 or 6.2. the 5.7 was mostly a car motor and not as common i wouldnt recomend them for truck use unless i just got it for the right price. not enough bottom end really. basically would be like a new truck in the old sheet metal. if you have a 4wd truck just find a new junked 4wd and gut it same for a 2wd. all are better than the older sbc imo.

Re: Why do I want an LS motor?
 

Okay. You guys got me. The new "Sith Lord Apprentice" has joined the dark side lol.

I'm 1000% going with a 5.3. But with a twist, and it starts with a "T", and ends with a "turbo"

Can anybody guess what that is?

Re: Why do I want an LS motor?
 

Twin Turbo... cause if it was a single, it starts with a "T", and ends with a "urbo" I would say single.... :lol:

Re: Why do I want an LS motor?
 

awesome but i will say this it is much easier to sc one of the engines than turbo.

Re: Why do I want an LS motor?
 

^this guy gets it!! Haha.



Yes it is. Especially since I've only just started learning about turbos but I'm up to the challenge. I think it'll be an interesting first build to say the least.. i happen to be a very creative person so the planning on paper portion will be stupid easy for me.. the hands on part should be entertaining for ya'll haha.

Re: Why do I want an LS motor?
 

Oh and by the way... this should be here early next week.