I have that too.
CK5
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'89 R3500 Crew Cab 2wd to 4wd conversion & beyond
- Thread starter mrk5
- Start date
Started out with 2wd TBI350 with SM465 to current 4wd with 454, 700r4, NP241
Since I first did the 2wd conversion, I've wanted to add some bracing to the front spring hangers. I had them made with 3" of drop to keep the caster in spec without needing angle shims and I always felt like it probably wasn't the best setup.
With the front clip out of the way, I took the opportunity to make a crossmember to add some extra support.
I just need to bolt the bottom brackets to the spring hangers. The plates on the ends of the horizontal tube are bolted through with the bolts that hold the spring hangers on.
With the front clip out of the way, I took the opportunity to make a crossmember to add some extra support.
I just need to bolt the bottom brackets to the spring hangers. The plates on the ends of the horizontal tube are bolted through with the bolts that hold the spring hangers on.
That is pretty beefy
It is. For projects like this, I scrounge the drop steel pile and the 2x3 was just the right length for the horizontal.
The angled pieces were rescued from a mangled steel sawhorse. There was just enough straight sections for the angled pieces.
I remember when you did this, I think it was about the time I was setting up leaf springs and we found out at the same time, your fix was much cheaper than mine.
I thought for sure yours would break and or bend, proved me wrong.
I might have just been getting away with it, barely. I've had at least 3 if not 4 hood pin failures; broken pins and tearing out of the core support. I wouldn't be surprised if the spring hangers contributed.
I think the heavy duty bumper probably helped keep things from being too bad.
I think the heavy duty bumper probably helped keep things from being too bad.
I thought so but then realized he did but wrong order.
So technically it could work with a shorter belt but he should just do it right
Bolted down the core support with some new poly body mounts. Then threw the radiator in to feel like I'm making some progress.
You can see the radiator tank ends up behind the driver headlight. Should still be able to plug it in.
You can see the radiator tank ends up behind the driver headlight. Should still be able to plug it in.
Holy big radiator batman
It's the equivalent of a 6.2L radiator for the squarebody trucks. I've been running it several years now. Technically the application was for a truck just like the L29 came out of so I figure I should keep the matched pair. It just so happens that 454 equipped GMT400 trucks have the same size radiator as a 6.2L equipped squarebody.
Also, don't forget I took about 10" out of the width of the core support. So normally it wouldn't be behind the headlight.
Also, don't forget I took about 10" out of the width of the core support.
So normally it wouldn't be behind the headlight.
I forgot about the narrow job. 
you mean the Nose job ?
I just wanted to make my radiator look big.
I finally have the Terminator harness thru the firewall! It may seem like a small victory but it's something that has had my analysis paralysis fully engaged. I ended up making my own pass thru using the original TBI hole.
I got the idea from searching to see what others had done. There are some you can buy on places like Amazon but they are really quite large. For comparison, mine has an overall diameter of 3.1".
I wanted one that utilized the existing hole for the TBI harness. I used 1/4" thick aluminum cut on our CNC router. There's a base ring bolted to the firewall that the 2 halves with the holes bolt to. I have a 3/16" radius roundover bit I used in the CNC to smooth the openings on the engine side. Unfortunately it's not very practical to cut both sides on the cnc so I used a step drill bit to bevel the back sides and then sanded them smooth. The harness doesn't have make a hard turn in the cab like it does in the engine bay so it won't be an issue. It took 2 tries to get it right so it has been a bit time consuming but I'm happy with the results.
I did get a little concerned about the big hole being too tight so it ended up a little bigger than needed. I will use some sort of foam "stuffing" to seal it up a bit better.
Like a dummy I connected all of the engine items first and I should have fed the harness thru from the cabin side first. It was a bit of a tight squeeze to get the harness relay thru the firewall hole. It's the relay base type that uses terminal connectors that un-pins thru the base instead of out the bottom so I couldn't just remove it entirely unless I was going to cut and splice wires. No thanks to that. The Terminator instructions want a 2" hole and the factory TBI hole is 2-3/16". The relay base would not have fit thru a 2" hole. It would have worked if I pushed the harness thru from the cabin first.
This is how much harness I have in the cab:
You can see the relay base there in about the middle.
I've been debating putting the ECU behind the dash or under the console. I have a couple ideas swirling around in my head. Luckily for now I can just connect the ECU laying on the floor so that my analysis paralysis doesn't further hold up getting the engine finally lit off for the first time. Of course there are still quite a few things yet to be done before the engine can start.
I got the idea from searching to see what others had done. There are some you can buy on places like Amazon but they are really quite large. For comparison, mine has an overall diameter of 3.1".
I wanted one that utilized the existing hole for the TBI harness. I used 1/4" thick aluminum cut on our CNC router. There's a base ring bolted to the firewall that the 2 halves with the holes bolt to. I have a 3/16" radius roundover bit I used in the CNC to smooth the openings on the engine side. Unfortunately it's not very practical to cut both sides on the cnc so I used a step drill bit to bevel the back sides and then sanded them smooth. The harness doesn't have make a hard turn in the cab like it does in the engine bay so it won't be an issue. It took 2 tries to get it right so it has been a bit time consuming but I'm happy with the results.
I did get a little concerned about the big hole being too tight so it ended up a little bigger than needed. I will use some sort of foam "stuffing" to seal it up a bit better.
Like a dummy I connected all of the engine items first and I should have fed the harness thru from the cabin side first. It was a bit of a tight squeeze to get the harness relay thru the firewall hole. It's the relay base type that uses terminal connectors that un-pins thru the base instead of out the bottom so I couldn't just remove it entirely unless I was going to cut and splice wires. No thanks to that. The Terminator instructions want a 2" hole and the factory TBI hole is 2-3/16". The relay base would not have fit thru a 2" hole. It would have worked if I pushed the harness thru from the cabin first.
This is how much harness I have in the cab:
You can see the relay base there in about the middle.
I've been debating putting the ECU behind the dash or under the console. I have a couple ideas swirling around in my head. Luckily for now I can just connect the ECU laying on the floor so that my analysis paralysis doesn't further hold up getting the engine finally lit off for the first time. Of course there are still quite a few things yet to be done before the engine can start.
I made the same mistake on mine when I did it. I ended up just punching a couple of 2” holes and making everything work. It’s messy but some of those seal it firewall gaskets will make it good enough.
Plugging away on wiring. Also trying to cleanup some unused and/or no longer needed wiring. I have 2 wires for the life of me I can't figure out what they're for.
I thought someone in the future might be curious how the LS1 Terminator X harness routed around the L29. I tried to keep the harness around the perimeter of the intake so it's possible to remove the upper plenum without needing to mess much with the harness. It is a little tight around the driver side but I think removing the plenum shouldn't be too bad. The biggest help was getting the MAP sensor and fuel pressure wiring under the throttle body.
It would be a little nicer looking if some of the connectors weren't so large.
I realized the cam sensor for the LS1 Terminator harness wouldn't plug into the L29 distributor/cam sensor. I had to rob the plug off the L29 harness which luckily is the same style just a different shape. The L29 plug is on the right.
I've been using the heat shrink labels. There's a learning curve of sorts. Like getting the label in the right spot to be visible but not under the seal for the connector.
They also work well for sealing off the end of the abrasion cover to contain all the loose strands.
Wired in a relay for the fuel pump. It's triggered by the Terminator pulling power off the battery bus. In theory I could have straight wired the pump according to Walbro's amp ratings for it, but after the trouble I had with the PF4 in the C10 I'm not taking that chance again.
I thought someone in the future might be curious how the LS1 Terminator X harness routed around the L29. I tried to keep the harness around the perimeter of the intake so it's possible to remove the upper plenum without needing to mess much with the harness. It is a little tight around the driver side but I think removing the plenum shouldn't be too bad. The biggest help was getting the MAP sensor and fuel pressure wiring under the throttle body.
It would be a little nicer looking if some of the connectors weren't so large.
I realized the cam sensor for the LS1 Terminator harness wouldn't plug into the L29 distributor/cam sensor. I had to rob the plug off the L29 harness which luckily is the same style just a different shape. The L29 plug is on the right.
I've been using the heat shrink labels. There's a learning curve of sorts. Like getting the label in the right spot to be visible but not under the seal for the connector.
They also work well for sealing off the end of the abrasion cover to contain all the loose strands.
Wired in a relay for the fuel pump. It's triggered by the Terminator pulling power off the battery bus. In theory I could have straight wired the pump according to Walbro's amp ratings for it, but after the trouble I had with the PF4 in the C10 I'm not taking that chance again.
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I don't think I've mentioned, I had to get extension harness for the crank sensor and the fuel pressure. The crank sensor needed more than 2' so it's a 3' extension.
The fuel pressure harness setup is a little silly. It's part of the driver side harness and it comes out all the way at the front of the engine. However the fuel lines/pressure regulator are at the back of the engine so I needed an extension to bring the harness back to the firewall. So it does a full circle of the intake with a 2' extension.
The fuel pressure harness setup is a little silly. It's part of the driver side harness and it comes out all the way at the front of the engine. However the fuel lines/pressure regulator are at the back of the engine so I needed an extension to bring the harness back to the firewall. So it does a full circle of the intake with a 2' extension.
You are getting close! 
Do you think one of those terminate yourself kits for the engine harness would have been a good idea?
In custom setups I would say yes
