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Topic Review (Newest First)
06-19-2019 08:44 PM
BrockGrimes clefspheare, If your current engine is still good a cheap option would be to stick a throttlebody off a v-6 or 350. Grab one from the junkyard and replace in internals, again cheap. While there grab a ecu they generally have a last 3 of the # on it of something like 747. The harness, and a few sensors, and chip can be bought from Affordable Fuel Injection or Howell. I've done a TBI swap for less than $500.
06-19-2019 08:01 PM
cerial Just pull out your 305 and install a 355/383.
Done simple and easy. Save a couple thousand not needing to change the fuel, exhaust, mounts, etc.

Respect the truck for what it is.
A work truck.
Squarebodies were not designed to go 90mph or have a 10 second quarter. Throw enough money at it and sure it can do those things. But there are better platforms that will do it better for less.

If you want better driveablity you can always grab a junkyard tbi system off a 5.0/5.7 and "hack" it using megasquirt or other system.

Mileage wise your realistically talking about 3-5 mpg. Anytime I have added power to something my foot tends to get heavier. Even going down in cubic inches with a small turbo in place of a large displacment v8 (454 to 3800) mileage tends to be about the same.

Best way I have found to get better mileage is to have a 30+mpg car and then a 10mpg truck.
06-19-2019 07:48 PM
CaptMike clefspheare

The truck LS engines are nearly all cast iron block and the yards sell good running usable engines with the ECM and engine wiring for in the $1K +/- area. Most Street Rod owners that I know all want the Camaro / Firebird or Corvette engines that are aluminum blocks.

Programming a power or econ tune, $250, including deleting the rear 2 Oxy sensors, speedo cal etc. in many places.

The weakest link for almost all LS engines are the roller Rocker trunions, usually a performance engine requirement - around $150 a kit.

use a 1999 or 2000 GM ECM and up to 2008. The E38 ECM 2005 to 2008 best choice.

If you shy at wiring of and an engine swap, do look for a valued shop. Get Shop customer references of previous LS swaps (installs) that you can speak with,,, preferably in person and view the vehicle !!

Wiring should be neat and orderly. Welding on the exhaust, mount / trans mounts, radiator, fuel lines and tank must be top quality or you'll have issues.

A $2k installed swap is a very good price if this includes of the labor, engine / trans, wiring, in-the-tank fuel pump, ECM re-programming and wiring harness mods which are always removing wiring that is not used in a conversion. Make sure you get this is a shop's written contract. Never pay UP FRONT $$$ to any shop, EVER. And get some sort of written warranty.

It's always better to purchase the entire donor car or truck so one receives all the parts they can from the vehicle, wreaked vehicles preferred. Saves $$$

Here's the engine bay in my '56 210. We made this upgrade conversion in 2007. Last summer I finally replaced the old headers with tuned BBK shorties. I've never had a single repair or failure on the LS1 / Tremic T-56 6 speed to date. Ls engines are fantastic great power and high reliability.

Good luck

06-19-2019 06:40 PM
Originally Posted by 39 master View Post
There are a ton of hidden cost with the 5.3 swap that you should know about before you start.
Yep. I have buddy who bought an LS1 and auto trans out of a wrecked Camaro for his 55 Chevy car. Pretty good deal for $1500. Well, around $3000 later, he still doesn't have everything to finish the job. He said he'd probably build an old skool 383 if he had a do-over.
06-15-2019 06:33 AM
55 Tony I have to ask again, will it all be worth the time and money? What kind of mileage would he expect after the swap? Maybe an LS I saw mentioned but if it's a 1999 like he looked at, mine is a 2000 and I get 10 - 12 mpg. I just turned 100,000 the other week (there was a few years I didn't drive it and now I only work part time). Mine is a 350 and it's a lame pig. Time for it's 100,000 mile tune up but it's always run the same.
06-15-2019 04:43 AM
75gmck25 Do you have an idea of your overall budget for the total upgrade? Swapping in and upgrading a traditional SBC 350 or 383 can be done through incremental upgrades, so it might be less painful and easier to manage the cash flow. Swapping in the LS 5.3 is a good alternative, but you have to buy a lot of parts up front and do a lot of work up front before you have a working truck.

The full LS conversion/transplant is very dependent on getting the computer system and wiring installed and working correctly, so getting help from an old-school mechanic might not be that effective. You already said you are not that skilled with wiring yourself, but for this project you really need to start studying and learning. It is not rocket science, but it does require careful labeling, good wire routing, and attention to detail for grounding and making connections. Make sure you have lots of space to lay it all out, and that you don't have to clean up and put it all away mid-stream just to get space for another project. Its really easy to lose track of where you were at if you have to box it all up for some reason.

If I was going to make the LS conversion I would prefer to buy a wrecked vehicle and pull the donor engine and transmission myself, making careful notes and lots of pictures as I went along.

06-14-2019 08:46 PM
Originally Posted by cerial View Post
What is your current drivetrain in the k10?
First post says 5.0L (305) and 700R4.
06-14-2019 05:46 PM
cerial What is your current drivetrain in the k10?
06-14-2019 04:03 PM
ericnova72 Just keep searching, got to be more than one wrecking/salvage yard near Spokane.

06-14-2019 03:54 PM
clefspheare It would be $1800 without the testing, I'm just guessing it would be an extra $200 for testing. Where would I find a cheaper one?
06-14-2019 03:39 PM
Originally Posted by clefspheare View Post
Well my local Spalding's shop says they have a conversion engine, (1999 5.3) with all the wiring and computer stuff, and they would pull it and test it, computers and all. It would be almost $2000 though. They're in Spokane Washington, is that a good price? It has 125k miles on it.
IMO, too much, you can find that entire package for 1/2 of that....I don't consider the "testing" worth the additional $1000.
That price is more in line with the bigger 6.0 or 6.2 engine package.
06-14-2019 03:20 PM
clefspheare I have a retired mechanic who attends my church, he say he'll help people with their mechanic work for like $20 an hour, and he usually works for $30 an hour. He would be able to help me with a lot of stuff. I'm a minor so that's why I know next to nothing. I ask a lot of questions, and research a lot, I really appreciate your guy's help.
06-14-2019 03:15 PM
clefspheare Well my local Spalding's shop says they have a conversion engine, (1999 5.3) with all the wiring and computer stuff, and they would pull it and test it, computers and all. It would be almost $2000 though. They're in Spokane Washington, is that a good price? It has 125k miles on it.
06-14-2019 03:03 PM
cerial The best way to improve your mileage is to park the truck and get a $800 kick around car.
It is one of those "hiden" cost that your going to need even if the thing is only down for a week or two. Honestly I would plan a month(working 8 days on the weekend for around 60 hours) even with everything "ready".

Even with everything laid out and planned there will be hiccups. You could have the thing running on a engine stand shifting a manual 4l60 with transfer case attached all out of the truck.

Lets say you have a sm465 to 205 or208 in that k10 currently(which eliminates many swap headaches) you still have the fuel pump, lines, tank(s), exhaust with 2 O2 bungs, diffrent clutch, flywheel, mounts, some minior electrical work for the motor(it wont be pretty but it will run by just splicing in the fuse box using the 2 wire trick after flash your ecm to turn off vats, then you need to give power to the starter lug feeding your main power junction to power the rest of the truck.

With everything in place and the 5.3 running on a stand your still looking at 20-30 hours to get the thing driving around the yard. Doing "clean it up later" things.
06-14-2019 03:01 PM
clefspheare I figure I'm going to try the 1999 lm7 5.3 as even though it doesn't pump out a whole bunch of power, it's probably the easiest to hook up.
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