93 Z71 97 LT1 Swap
03-19-2010, 01:24 AM
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93 Z71 97 LT1 Swap Well the swap has officially started and I figured I'd try to document it best I can. This is a 1993 Chevy Z71 with a 350 TBI and a 4L60E tranny. The donor is an LT1 engine and computer from a 97 T/A.
-Electrical - I've decided to use the factory harness from the LT1 and doing a little splice work. More details on this when I get there.
-Accessories - I debated on using the Vette bracket to relocate the accessories to the driver side but after careful measuring I don't think that will be necessary. I am going to use an A/C delete pulley for now and later on install an A/C relocation kit I found on Bowers Race and Rod Shop to mount the compressor high on the driver side. Will also have to have custom A/C lines made, but that will be later. The 2/80 A/C will have to work for now.
-Power Steering - The power steering lines will fit into my gearbox and the reservoir will be mounted on the passenger side of the engine compartment.
-Radiator - I will be using the T/A radiator for ease of routing the coolant hoses.
-Fuel - I bought and installed an intank fuel pump for a T/A and used the factory sending unit from the truck. I think that I'm going to take the easy way out and use rubber fuel line from the truck lines to the fuel rail.
-Exhaust - I already have Flow Tech shorty headers that I will be using with a high flow cat and Flowmaster 40 series muffler dumped before the axle.
- The old TBI will be out, engine compartment cleaned, and LT1 stabbed tomorrow. Then the real fun begins. I will keep this updated.
-Electrical - I've decided to use the factory harness from the LT1 and doing a little splice work. More details on this when I get there.
-Accessories - I debated on using the Vette bracket to relocate the accessories to the driver side but after careful measuring I don't think that will be necessary. I am going to use an A/C delete pulley for now and later on install an A/C relocation kit I found on Bowers Race and Rod Shop to mount the compressor high on the driver side. Will also have to have custom A/C lines made, but that will be later. The 2/80 A/C will have to work for now.
-Power Steering - The power steering lines will fit into my gearbox and the reservoir will be mounted on the passenger side of the engine compartment.
-Radiator - I will be using the T/A radiator for ease of routing the coolant hoses.
-Fuel - I bought and installed an intank fuel pump for a T/A and used the factory sending unit from the truck. I think that I'm going to take the easy way out and use rubber fuel line from the truck lines to the fuel rail.
-Exhaust - I already have Flow Tech shorty headers that I will be using with a high flow cat and Flowmaster 40 series muffler dumped before the axle.
- The old TBI will be out, engine compartment cleaned, and LT1 stabbed tomorrow. Then the real fun begins. I will keep this updated.
03-20-2010, 03:41 AM
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Day 2 and the LT1 is sittin' pretty, well it's sittin', in the truck.
Just a little background on this project. This is a semi-daily driver and I'm working with a very short time frame here. So, cleanliness has taken a backseat to functionality and time constraints. I mention this because normally I would have cleaned up the engine compartment and parts much better if I had more time. It will be cleaned up once all is operational. Anyhow...
The old TBI has hit the ground and been rolled out the door.
I replaced the factory fuel sender, cause it hasn't worked since I bought the truck and installed a new 45 psi in-tank fuel pump.
I used the original motor mounts and the motor slid right in as though it was meant for the truck.
The flywheel cover did have to be trimmed slightly around the starter because the original had a different offset apparently. Nothing a sharp blade and power tools couldn't take care of.
The A/C delete bracket came very close to the sub-frame support but it cleared.
Installed the drivers side header and then realized I needed to weld an O2 bung (great word btw) onto the passenger side header collector, which will be done in the morn.
The 4x4 has an oil filter adapter that mounts the filter sideways to clear the front drive shaft and has oil cooler lines that went to the original radiator. I omitted this and went with a shorty filter since the T/A radiator doesn't have an oil cooler. I don't do a lot of towing and don't think this will cause an issue with oil temp, but I'm contemplating adding an external cooler later.
The wiring fun starts tomorrow and hopefully will go smooth enough thanks to alldata wiring diagrams. Radiator mounts, mounting the P/S reservoir, and ECM are also on the list for tomorrow. Full day planned, thank goodness for energy drinks and good weather.
I'm going to post a link to the pics on my Facebook, let me know if it doesn't work and I will post here instead. http://www.facebook.com/album.php?ai...0&l=e42c1665a0
Just a little background on this project. This is a semi-daily driver and I'm working with a very short time frame here. So, cleanliness has taken a backseat to functionality and time constraints. I mention this because normally I would have cleaned up the engine compartment and parts much better if I had more time. It will be cleaned up once all is operational. Anyhow...
The old TBI has hit the ground and been rolled out the door.
I replaced the factory fuel sender, cause it hasn't worked since I bought the truck and installed a new 45 psi in-tank fuel pump.
I used the original motor mounts and the motor slid right in as though it was meant for the truck.
The flywheel cover did have to be trimmed slightly around the starter because the original had a different offset apparently. Nothing a sharp blade and power tools couldn't take care of.
The A/C delete bracket came very close to the sub-frame support but it cleared.
Installed the drivers side header and then realized I needed to weld an O2 bung (great word btw) onto the passenger side header collector, which will be done in the morn.
The 4x4 has an oil filter adapter that mounts the filter sideways to clear the front drive shaft and has oil cooler lines that went to the original radiator. I omitted this and went with a shorty filter since the T/A radiator doesn't have an oil cooler. I don't do a lot of towing and don't think this will cause an issue with oil temp, but I'm contemplating adding an external cooler later.
The wiring fun starts tomorrow and hopefully will go smooth enough thanks to alldata wiring diagrams. Radiator mounts, mounting the P/S reservoir, and ECM are also on the list for tomorrow. Full day planned, thank goodness for energy drinks and good weather.
I'm going to post a link to the pics on my Facebook, let me know if it doesn't work and I will post here instead. http://www.facebook.com/album.php?ai...0&l=e42c1665a0
03-20-2010, 09:31 AM
#7
thats gunna be badass when yur done, and as far as cleansliness, screw it for now. You'll have PLENTY of elbow room to clean up and work on the motor when you get it runnin under the hood of that silverado...
Now if ya'd just stroke it and throw a lil juice on there
jk good luck man!
Now if ya'd just stroke it and throw a lil juice on there
jk good luck man!
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03-20-2010, 12:18 PM
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The speedo, coolant temp, oil pressure all use the same style sensor, so I'm going to use the factory gauges for now. Dakota Digital instrument panel in the future.
The original cover for the LT1 would've worked but being 4x4 wanted to retain the "beefed up" cover.
And thank you everyone for the comments.
03-22-2010, 02:15 AM
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Yesterday, i worked on the wiring. The original ECM is behind the glove box in the truck and the engine wiring comes in through the firewall just under the coolant reservoir. I cut all the original sensors off at the firewall and connected the harness to the engine and tranny. Also ran the wires for the 4wheel drive components. Plan on splicing the wires that go inside the passenger compartment into the wires coming out of the firewall next week. I go back to work tomorrow and won't have a chance to work on it till next tues. I was going to spend a little time on it today but my buddy came up with tickets to the Dallas Stars game. Gotta hate diversions. LOL So, my baby sits till next week after I get off of work from the rig. Be back soon.
04-01-2010, 01:12 AM
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Problems So, everything is wired up, used Jet DST to delete all emissions nonsense and VATS that I'm not using, started and ran beautifully. However, took it on the initial test drive and in Drive it wants to start out in 3rd gear. It will shift into first if the gear selector is put in 1, but even at WOT it won't downshift. Grrrrr. My only other issue I'm having that might be related to this is the fact that the VSS is reading way to high. It was showing I was doing 60 when actually it was only about 25mph or so.
So my question is... Could the PCM seeing the wrong speed cause the truck to start out and stay in 3rd?
So my question is... Could the PCM seeing the wrong speed cause the truck to start out and stay in 3rd?
04-02-2010, 01:37 AM
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Ok I'm pretty sure the VSS is the culprit but I have a question. The VSS on the truck is mounted on the transfer case, obviously,on the trans am it was on the tranny. How do I go about mounting a VSS on the tranny or making the one mounted on the transfer case work? Is it possible to mount a reluctor ring on the output shaft and drill a hole for a VSS from a car?
Also, the truck has a speedo buffer in it. That the VSS was wired to then it sent the signal to the speedo and ECM. The TA PCM has a direct input for the VSS and a single wire output for speedo, cruise, ABS, etc.
Also, the truck has a speedo buffer in it. That the VSS was wired to then it sent the signal to the speedo and ECM. The TA PCM has a direct input for the VSS and a single wire output for speedo, cruise, ABS, etc.
04-02-2010, 02:44 AM
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Or I could set the speed calibration to work with what I have in the truck now, because that's why I bought the programmer after all. Geeez, I love answering my own questions. I'm going to bed. 
04-16-2010, 03:32 PM
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Alright, so after swapping PCM's and finally taking care of the limp mode problem. I got the truck started and what do I hear? How about a knock, which was the original reason I started the swap in the first place. So the engine is back on the stand and completely torn down. #8 Cylinder spun a bearing and every top piston ring was destroyed and found a few flat lobes on the cam. Getting a crank and cam tonight, already have new bearings and rings waiting to go in. Is this a common problem with the top rings being blown to bits? To me it's odd that every single one of them was messed up. I guess this explains my blow-by problem as well. 
05-03-2010, 07:57 PM
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As of Monday night the engine was in and running. What an absolute relief to start this thing and not hear any internal noise. The truck is an absolute dream to drive now, well worth the few issues I ran into along the way. Now it's time to play with the programming, shift points, etc. Does anyone have any suggestions of where to start programming with the Jet DST Tuner? I've used a bit to turn off all the emissions and other crap that I didn't end up using. I have a few pics from my phone, I'll stick some better pics and a few videos later. Hope to have a few time slips in the next few weeks as well.
