Stovebolt.com Forums The Parking Lot '73-'87 Trucks -- "The Rounded Line" LS swap

My 1986 half ton pickup has a tired 305. Runs well but smokes a bit. People tell me to throw the 305 away and put in an LS. I could also use an OD transmission. I'm kicking myself for scrapping my 5.3 with OD several years ago in my Savana. What exactly do I have to gather ahead of time to do this swap?

I am planning a 6.0 LS swap in one of my '59s. I purchased a book.

LS swaps into almost anything [barnesandnoble.com]

I will probably try and find a wrecked truck for the powertrain when it warms up.

John

If you have a friend in the auto insurance business you can ask him/her to help you get a wrecked truck or car with a mid mileage LS from the insurance pool. Should save you a bunch of $ over buying one from a salvage yard. You can get the engine, computer and all the necessary stuff from one vehicle then scrap out the rest to put some cash back into the project. Just be sure to get 2wd unless your making a 4wd project.

I am currently in deep in this very situation. ‘70 C10

Things to consider:
Computer and wiring: I’m not here yet but will be shortly. I will be using information from this website to help me. It is a bit overwhelming for a rookie/newbie. I still nervous, but as my fix anything, ole boy, hit it, old friend of Dad neighbour used to say, “A man built it. We can fix it ( or in this case hot rod it)!😉

http://lt1swap.com/

Fuel system: you will need to figure out the fuel pressure system to the rails on the intake. Return? Returnless? Fuel filter setup/regulator? Stock tank? After market? Can get pricey.

Engine mounting. This is not a bolt in with stock items. There are many kits available to mount the ls into just about anything. I used Dirty Dingo, so far so good during mock-up.

Emissions? What are your state’s laws? Does your truck have emission equipment? Does the state require you to keep it? Look into it. It might cause you grief if you don’t. Not to mention money. Up here, smooth sailing for me with just about anything.

Active fuel management/deactivation came in around 2003/2004 (don’t quote me), and will be a factor in which truck donor you get.

Front belt setups: make sure your gathered parts play nicely and line up on the front of the engine. I’m sticking with the awful looking truck setup. Cheap and it looks ok with some cleanup and paint.

Trans mount should be ok to use.

A/C? - the stock 5.3 truck compressor JUST clears the frame, when bare and nothing hooked up. I suspect I will have to notch the frame rail slightly if I use a stocker.

Radiator: trans cooler included? The fittings will be different possibly and routing. I’m investigating this.

Steering: the modern pump might use a different fitting. I am researching this right now, too.

Exhaust: the stock truck 5.3 will not clear the frame rail. I heard people say, “NOTCH THE FRAME,” but my mock-up experience showed a ridiculous amount of notching, to the point of frame integrity being lost. Get new manifolds.

Trans control: will the tranny talk with your gauges? Look into this. I am too.

Wrecker truck: agreed. I got my truck for $900. 215,000km/ 130,000mi. Engine, trans, computer, etc minus the alternator and steering pump. THe front seats had been sold, but I suspect I might make back $200 on the axles, tires, etc. Plus, now I have extra door handles for when my ‘04 Duramax latches break. It happens. -40°...stuff gets brittle. I haven’t driven it in over a week!

4wd vs 2wd? I bought a 4wd truck, but had the transmission overhauled because of 3/4 being burned out. The shop switched it from 4wd to 2wd for me. Since computer will be reflashed, I wasn’t concerned about it.


It is a pile of extra work in my mind. Time will tell if I ever do it again. I have to drive it to see.

I’m still plugging away at it. 8 months later, still here...Mind you, I am doing a frame off build.

The snowball effect.

Thanks for that, Fox and the rest. I think I'll put up with a bit of smoky exhaust, at least for now.

I have gone pretty far with the help of others. I bought a “rebuilt” 2003 5.3 engine. I have it running on a run stand but am disappointed with compression in 3 cylinders. I plan to use the engine as is and maybe things will improve.
There are many fiddle factors to deal with. Among them are
Choice of oil pan
Accessories brackets
Drive by wire or cable for the throttle.
Factory wiring harness and flashed ECM or Aftermarket wiring and ECM

I bought the Holley Terminator X wiring and ECM because it is self learning and shouldn’t require paying someone to tune the engine.

Depending on your knowledge base, this will be a fun adventure. I knew nothing about fuel injection and ECMs. I’ve enjoyed learning.

Get your wallet out and get ready for the long list of “stuff” you’ll likely need to buy.

Here’s a video of my engine on a run stand. It’s not in the truck yet.
https://youtu.be/m39xQD7HrCg

So if it already has a small block Chevy engine, then why not just put a beefier one of those in there? Everything will bolt right up, you could probably do it in a weekend. And it's not like the SBC isn't just about the most well supported and hot rodded engine in the world. Or that it wouldn't make plenty of power for whatever you're doing.

Sure the LS is awesome, but it seems like a lot of work to do not much if any more than the small block the truck came with-but with a whole bunch of extra work and expense.

I put a Cadillac V8 in front of the stock drivetrain on my '65 Chevy C60 school bus.. so I got to learn a little bit about putting it where it wasn't intended to be