89-93/V6-V8 engine swap resuts
cdoogles
12-01-2004, 10:35 AM
For the past 2 weeks I have been spending my nights on an engine swap. I totaled my 1989 k1500 5.7L. a few months back, and of course this was directly after the completion of my engine, tranny, and rear-end rebuilds. So, rather than have all that hard work go to waste, I decided to swap the running gear into another rig. I picked up a 1993 k1500 4.3L with a straight body for a decent price and went from there. So the swap I was attempting was not only V6 to V8 but also a 4 year gap. Not that big of a deal I assumed. Well I got it started up this saturday, and here is a list of the problems I ran into so far...I'm sure there will be a few more too trouble shoot as I rack up a few miles.
1. Motor Mounts are way different. Not just the frame mounts but the engine brackets also. New mounts were 35.00 each, and I used my original engine brackets.
2. Different size radiators. 250.00 at autozone with a lifetime warranty.
3. Fuel lines off either truck would not work. 1989 had steel braided lines that weren't long enough because of different fuel filter locations. 1993 had hard lines that would'nt bend quite right to line up. Ended up cutting the hard lines where they came over the top of the block and then again about 2" from there ends and patching with some high quality rubber fuel lines. Seems to work fine and hold pressure.
4. Swap wire harnesses and computers. The computers are not interchangeable, as the harness plugs are different.
5. Two wire plugs still need to be spliced. One, behind the glove box by the computer. Haven't traced it yet but it's a larger red wire coming from the drivers side, over in the 89, and in the 93 it's a larger red wire plus 2 signal wires. The 89 enien ahrness only has a single wire plug so Ijust capped the other two wires for now...might be an issue later, we'll see. Second plug, in the engine compartment by the firewall plug on the drivers side. Looks identical, but they swapped male and female ends. Just run's to the rear end lighting so splice in one male plug to match the female on the other end.
6. A/C system. Original plan was to save my R12 and not drain the system. Unfortunately wiring harnesses are different. 1989 has two plug, while 1993 has only one. So, if you swap the compressors, you'll find that the silver hose fitting on the back of the compressor doesn't quite match up. It's close but no cigar. So I used the 1989 compressor, hoses, and now I need to get a new A/c Condenser cause the fitting from the top hose to that are different. The rest of the system seems like it will work though.
7. Transmissions are different. 1989 has a 700R4, while the 1993 has a 4160E. I realize the latter is the better tranny, but since mine was just rebuilt and the wiring harnesses are way different I decided to go with the 700R4 for now. Never disconnected the tranny doing this either. The package pulled pretty easily.
Other than this stuff It was pretty straight forward! just a weekend project..no big deal. Now time to finish the lift kit and get some new paint on her.
1. Motor Mounts are way different. Not just the frame mounts but the engine brackets also. New mounts were 35.00 each, and I used my original engine brackets.
2. Different size radiators. 250.00 at autozone with a lifetime warranty.
3. Fuel lines off either truck would not work. 1989 had steel braided lines that weren't long enough because of different fuel filter locations. 1993 had hard lines that would'nt bend quite right to line up. Ended up cutting the hard lines where they came over the top of the block and then again about 2" from there ends and patching with some high quality rubber fuel lines. Seems to work fine and hold pressure.
4. Swap wire harnesses and computers. The computers are not interchangeable, as the harness plugs are different.
5. Two wire plugs still need to be spliced. One, behind the glove box by the computer. Haven't traced it yet but it's a larger red wire coming from the drivers side, over in the 89, and in the 93 it's a larger red wire plus 2 signal wires. The 89 enien ahrness only has a single wire plug so Ijust capped the other two wires for now...might be an issue later, we'll see. Second plug, in the engine compartment by the firewall plug on the drivers side. Looks identical, but they swapped male and female ends. Just run's to the rear end lighting so splice in one male plug to match the female on the other end.
6. A/C system. Original plan was to save my R12 and not drain the system. Unfortunately wiring harnesses are different. 1989 has two plug, while 1993 has only one. So, if you swap the compressors, you'll find that the silver hose fitting on the back of the compressor doesn't quite match up. It's close but no cigar. So I used the 1989 compressor, hoses, and now I need to get a new A/c Condenser cause the fitting from the top hose to that are different. The rest of the system seems like it will work though.
7. Transmissions are different. 1989 has a 700R4, while the 1993 has a 4160E. I realize the latter is the better tranny, but since mine was just rebuilt and the wiring harnesses are way different I decided to go with the 700R4 for now. Never disconnected the tranny doing this either. The package pulled pretty easily.
Other than this stuff It was pretty straight forward! just a weekend project..no big deal. Now time to finish the lift kit and get some new paint on her.
randy78
12-01-2004, 10:52 PM
neat :D
you take exhaust off a donor, or ?
or just need v8 manifolds only ?
could yo have used the v6 radiator at all ?
you take exhaust off a donor, or ?
or just need v8 manifolds only ?
could yo have used the v6 radiator at all ?
cdoogles
12-02-2004, 09:48 AM
I used the stock manifolds on the V-8. The exhaust on the V-6 mated right up to it though. I'm leaving that on for a few days of test driving and then I'm putting some dual magna-flows on. The V-6 radiator would work, but getting the tranny cooler and oil cooler lines to line up was going to be a bit of a hassle. I figured I'd rather have a bigger radiator anyway and not mess with bending the lines around the fan shroud.
Cam7
12-04-2004, 06:22 AM
In a way its good that you used your 700r4 trans. Your ABS wouldnt work if you used the 93. There is a sensor ring on the Trans output shaft that gets a signal from the speed sensor that controls the ABS rear braking. Almost found out the hard way went to do a Trans swap and happened to check the speed sensor was different. Checked the wiring of the sensor found that it controlled the ABS. Found a diagram of the ABS system and showed the sensor ring on the output shaft. Never would have figured that. System shows 88-91.
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