98 Silverado LM7/SAS project

Hey guys I have finally begun my project.

Project truck is a 98 C1500 that is getting a LM7/4L60e 4x4 combo. I am doing a SAS on the truck as well.

Parts I've gathered so far:
-LM7/4L60e w/ Tcase out of a 99 K1500 (complete donor truck). Rebuilt trans, 114k on the engine
-Programmed PCM
-Harness just got sent to Nelson this afternoon

I still need to aquire quite a bit.
-Headers
-Misc exhaust parts
-EGR Delete kit
-CAI
-Dana 50/60
-Plugs and wires
and the list goes on and on...

I worked out a deal for an entire 99 LM7 truck. I just had to make the guy a set of bumpers.
http://i84.photobucket.com/albums/k4...m/f0baf12e.jpg
http://i84.photobucket.com/albums/k4...m/fa9ccdda.jpg

Here's the project truck.
http://i84.photobucket.com/albums/k4...m/74243e7e.jpg
http://i84.photobucket.com/albums/k4...m/e84c726d.jpg

Slight frame damage...Need to figure out how to make it match the drivers side since that is where the SAS brackets are going to be going.
http://i84.photobucket.com/albums/k4...m/ec0aceb3.jpg
Any ideas??

LT1 and LM7 hanging out
http://i84.photobucket.com/albums/k4...m/807c5e66.jpg

Somewhat at a standstill right now. I would like to do the axle swap before I drop the motor in for ease of install but craigslist is looking pretty slim for the past week on axles. Not to sure on the game plan at the moment.

Next step is to swipe the card and get some parts to my door.

I will keep the thread updated with progress and plenty of pictures.

Thanks for looking!

That is one hell of a bumper. Looks real nice man.

Should be a fun swap when its done.

Could always just go links or radius arm if you cant get the frame fixed.

Lookin good!

Thanks guys. I hope to get it done with a cheap budget. I wish I had more time to clean it up right but this is my DD so got to get it on the road. Its going to get muddy again anyhow :thumb:

Had links on my last truck and realized how expensive they are haha. Im going to stick with leafs for the cost.
http://i84.photobucket.com/albums/k4...S/7ed58e5d.jpg

Got the 5.3 in for the most part
http://i84.photobucket.com/albums/k4...m/ecd394b8.jpg

Heres a view from the top of the frame
http://i84.photobucket.com/albums/k4...m/d09b790e.jpg

Have not come up with anything yet. The shape of the frame is given me a hard time.

Why oh why did you sell the last one? haha

Plan on using rear 52'' spings?

Where you located any way?

I HATED to sell that truck but it had to be done. I was going to put a Cummins in it but after buying 4 different axles, links, etc... funds dried up real quick. It was an awesome truck I loved it. It was the first full build I did.

http://i84.photobucket.com/albums/k4...S/0893116a.jpg
http://i84.photobucket.com/albums/k4...S/IMG_1855.jpg

Yea I am going to use 52s up front. Still searching for a set. I have a lead on some SD axles in SC but they are 6 hours away. Might have to make the long haul for them.

I live in good ole Milledgeville GA.

Cool project. Been there to the orv once. Nice place.

Cant wait to take mine there once its done! Some rumors were going around about it getting shut down..I never heard the verdict though.

Tomorrow I got to remove a broken manifold bolt, fix the exhaust flange on the stock manifold, make transmission crossmember and mount the motor. Should be a productive next few days.

Thats where i recognized that user name! I followed your whole build on your last truck on pirate!

Got a little bit done over the past few days, not much to show pictures of though.

I have the engine/transmission in its final resting place, got the Trans xmember modified, made an EGR block off plate, spark plugs and wire in, fuel lines run and a few other odds and ends.

http://i84.photobucket.com/albums/k4...m/3c08bbba.jpg
http://i84.photobucket.com/albums/k4...m/22110c8e.jpg
http://i84.photobucket.com/albums/k4...m/a751e7c8.jpg
EGR blockoff
http://i84.photobucket.com/albums/k4...m/8194770d.jpg

Not much left to do. Waiting on my harness before I put the front core back together.

Few questions:

Whats the best way to use either the OBS or NBS coolant reservoir? The NBS has a much larger hose fitting at the bottom of the reservoir compared to the OBS. Not sure what to do on the plumbing for this part.

I am relocating the battery to the drivers side, does anyone have any pictures of how they mounted it? Going to do a search in a minute.

I also am ditching the ABS. I need the line nut sizes for the front brakes that go into the ABS brain. Cant seem to locate that information anywhere.
http://i84.photobucket.com/albums/k4...m/8d6a5a63.jpg
(its the 3 small lines)

Thanks for the help

Got a good bit done yesterday.

Biggest accomplishment was relocating the battery tray.

Cut the tabs off the old bracket
http://i84.photobucket.com/albums/k4...m/3ebde4dc.jpg
Mock up for the leg
http://i84.photobucket.com/albums/k4...m/f2209fa1.jpg
http://i84.photobucket.com/albums/k4...m/6d7b82bc.jpg
Finished
http://i84.photobucket.com/albums/k4...m/5e8cb33a.jpg

I've got everything ready to go just waiting on the harness. Still not sure how to plumb part of the cooling system and which reservoir has been working best.

What are the wires that come out of the passenger side firewall on the LT1 harness?

Going to the junk yard today in search of a driveshaft

Quote:

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Originally Posted by iridektm

http://i84.photobucket.com/albums/k4...m/8194770d.jpg

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Wanna make me one and mail it over? :lol:

Ive been meaning to make one myself for the last 2 years it seems and just never get around to it. :laugh:

For the brake line ends, i had to reuse mine. Think they are metric though.

FWIW, I used a Moroso expansion tank on my last project OBS truck I did.
http://www.ls1truck.com/forums/showt...746#post188746

FWIW, a new factory left hand mount battery bracket is cheap from GM. I did one on this project, too.

Quote:

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Originally Posted by bangbangskeetskeet

Wanna make me one and mail it over? :lol:

Ive been meaning to make one myself for the last 2 years it seems and just never get around to it. :laugh:

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Send me a PM

Quote:

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Originally Posted by tanz45

For the brake line ends, i had to reuse mine. Think they are metric though.

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I am trying to find the line nut size so I can buy a Tee fitting to fit the line nuts when I ditch the ABS unit. I plan to reuse the stock line nuts just cant find there size anywhere. Did you keep your abs?

Quote:

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Originally Posted by RedHeartbeat

FWIW, I used a Moroso expansion tank on my last project OBS truck I did.
http://www.ls1truck.com/forums/showt...746#post188746

FWIW, a new factory left hand mount battery bracket is cheap from GM. I did one on this project, too.

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I found a couple expansion tanks at the junk yard today. K10 tanks should fit and I found a few Silverado tanks that might work. Also found a few trucks that have the same front frame horn as me with zero damage. I am wondering if I could cut the junkyard frame horn off and somehow fit that back on...

I found a battery tray on eBay for cheap but had a day of leisure working on the truck so figured I would mess around with the tray.

Jon at Nelson Performance called today. The harness should be back to me on Friday. Cant wait to get it in.

I will be home from school for the break so there will be some downtime. The goal is to have the swap finished and driving before next semester starts.

I ditched it entirely, was on a 99. Just got a prop valve off of ebay since the factory prop valve was in the ABS module.

Quote:

---

Originally Posted by RedHeartbeat

FWIW, I used a Moroso expansion tank on my last project OBS truck I did.
http://www.ls1truck.com/forums/showt...746#post188746

FWIW, a new factory left hand mount battery bracket is cheap from GM. I did one on this project, too.

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hey im currently facing the same issue. any part numbers for these?

Use this and mount where ever u want. I put mine underneath on the frame rail

http://www.jegs.com/i/JEGS+Performance+Products/555/10222/10002/-1

Quote:

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Originally Posted by tanz45

I ditched it entirely, was on a 99. Just got a prop valve off of ebay since the factory prop valve was in the ABS module.

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Do you happen to have the part number for the prop valve? Its a 2 in 3 out?

Thanks

edit: this look right?
http://www.summitracing.com/parts/RSD-PV72/

what are u planning to do about a/c?

Quote:

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Originally Posted by iridektm

Do you happen to have the part number for the prop valve? Its a 2 in 3 out?

Thanks

edit: this look right?
http://www.summitracing.com/parts/RSD-PV72/

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Yup, looks good to me as long as you are doing 4 wheel disc. If you are doing drums in the rear, make sure you do a disc/drum prop valve.

I am back home for good and will be working on the truck everyday until it is finished. I am wiring it right now and feel like I am in over my head even with the nelson harness. This is my first time ever tackling an engine swap or dealing with any engine wiring.

I am not sure what all I need to retain from the 98 truck, as far as wiring is concerned. I am running just the LS PCM and am going to use the 98 power center for the starter and IGN wire. Do I need anything else from the power center other than one pink and the big purple? After stripping the harness down I now have a bunch of loose wires coming from the power center, and the block that bolts into the firewall below the brake booster. What should I do with them? I have already removed the entire LT1 engine harness part from the control center of the 98 harness. All I have left is the block that bolts into the firewall and the power center. The connection on the Pass side where the wires go inside the cab I think I can completely delete, correct?

Also I traced the fuel pump wires into the engine bay where it comes to the square connector. I have the other end of the square connecter but it is completely cut free. Do I still just tie my fuel pump wire on the nelson harness to the gray wire on the fuel pump?

Thanks I will post pictures very soon

LT1 Harness before I got out the cutters. I think I might have gotten a little cutter happy. I sure hope not.
http://i84.photobucket.com/albums/k4...m/f65b984a.jpg

What I removed
http://i84.photobucket.com/albums/k4...m/f9bda95b.jpg

Power center I am left with
http://i84.photobucket.com/albums/k4...m/8baf808e.jpg

Pass side firewall bundle
http://i84.photobucket.com/albums/k4...m/d139338b.jpg

The square plug on the firewall, is that for the fuel pump?
http://i84.photobucket.com/albums/k4...m/a237fad0.jpg
Here is the end that plugs into it, that now is free.
http://i84.photobucket.com/albums/k4...m/6add40ab.jpg
I have the fuel pump wire from the nelson harness along with the relay from nelson, I also found the grey wire from the fuel pump but it ends at that square plug which now goes no where since the other end is free.

Any help is appreciated, right now I dont have any idea what to do next.

Thanks for any help

Power center in the truck.. wires going to the left are mostly free, wires to the right go to the junction block on the firewall below the brake booster
http://i84.photobucket.com/albums/k4...m/ee64e6d9.jpg
http://i84.photobucket.com/albums/k4...m/9e84714d.jpg

I have a bad feeling that I got a little crazy cutting the wires.

What an FN mess. I'm glad it's you and not me working on that one! :lol:

You had and LT1 engine in there? What did it come out of?

The way I find what I need is to put the factory harness, or what remains of it, back in the truck with 12v and turn the key on to different positions to see what gets energized in which positions. You're only looking for a couple power wires for the NP harness.

I know its a mess and is stressing me out. Yes the previous motor was a 5.7L LT1 and the truck year is 1998.

Not much remains of the factory LT1 harness as you can see, its all cut up. Do I need to get another LT1 harness or do I not need anything from it?

I hooked the PCM up, the battery, all the grounds, IGN, and purple wire to the starter wire and turned the key to see if I had power and had nothing. I have the reworked nelson harness hooked up everywhere correctly to the motor.

This is my first time tackling any motor wiring and I have no one next to me to help with or without experience. Might have bit off more then I can chew.

any idea what this plug is?
http://i84.photobucket.com/albums/k4...m/bdb82cc8.jpg

If the engine that is on the floor is what you're calling an LT1, that's doesn't look like one but looks like a vortech 5.7L engine since the tb points upwards.

Anyhow, you need to put the wiring back in the truck and hook up power and then start looking for a lead the get 12v signal or 12v ground when the ignition is triggered. Be sure you have the parking brake set, trans selector in park and if it's 4wd that it is in a range in which it will be allowed to trigger the ignition. Be sure there is power going to the steering column when the key is on. With all the wires you cut out of the harness you may have cut a lead that sends power into the truck.

Taking another stab at it today. Stayed up all night reading what I could find hopefully I will make some progress today. Thanks for all the help