5.3L LS checklist with part numbers

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iamtherealJayy

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Since the 350 in my 1978 Chevrolet K10 is getting tired and I need a clutch swap anyways I’m going to swap in an LS for better fuel economy and power. Currently I’ve picked everything except the fuel tank, sending unit, and pump. The things I’ve got so far:
-ICT billet sbc to LS motor mounts
-ICT billet sbc to LS coolant sensor adapter
-ICT billet 12.9 ls flywheel bolts
-Larlansz M16x1.5 to 1/8 npt oil pressure sensor adapter
-SACHS NFW1050 flywheel
-ARP 134-2203 pressure plate bolts (12” clutch)
-GM ACDelco 12557583 pilot bearing
-Power Torque K1909-02 12” clutch kit
-generic -6AN fuel line and fitting kit
- ls quick connect 3/8 to -6AN
- ls quick connect 5/16 to -6AN
For fuel tank I plan on using the GM1C baffled 87 tbi tank and sending unit with an upgraded pump(haven’t picked which yet) my truck is going to retain the stock ls with 0 power modifications. I’ve read between a few options including the walbro 255, and a late 90’s gmt400 stock fuel pump. My current total in just parts, adapters, etc is around $400. After I order the tank and fuel pump that will add around $250. I’m going to pick up a stock early 2000’s drive by cable 5.3 with an already worked harness ready to drop in. I’m mainly making this to ask is there anything I’m forgetting? I’ve been trying for three days now to make sure I had everything before I hit order. I also wanted to share part numbers of everything I’ve ordered so far.
 

iamtherealJayy

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I committed to a fuel system,
-Spectra GM1C baffle tank
-87 tbi fuel sending unit
-GM ACDelco EP381 fuel pump
-Generic -6AN fuel filter
Fuel system should be good enough for stock. Im currently sitting at $628.92 in all the parts listed. I still need to go to oreillys to get the power torque clutch for around $100 so let’s say $750 total for parts to get the engine going. The engine drop in ready is $1300 so roughly $2000 for an ls swap.
 

TotalyHucked

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You've gotta come up with a regulator of some kind, whether it's an aftermarket one on the firewall or OE style. On my LS swap, I'm running an '06 Corvette regulator/filter combo down on the frame. It's spec'd for the proper 58psi and is available at any parts store. Earls has the adaptors to put over the ends on it to convert to AN. I only run Wix or AC Delco though, because my tuner buddy has had nothing but problems out of any other brand.
 
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Hunter79764

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If you run the earlier return style fuel rail (which should be easy to find on a pull-out motor), you do not need a standalone regulator. It is the better design, but GM dropped it for cost savings later in the run. But you will need to make sure you have a good return line (5/16" preferably).
What's your plan on exhaust manifolds/pipes?
Stock radiator should be fine. Planning the mechanical fan, or late model electric? They can be had for not too much money, and it might simplify the shroud situation, depending on mounts/position/actual truck it might be a perfect fit or you might have to tweak some stuff.
I'm guessing you are using setback plates to keep your existing transmission in place, right?
If your donor engine has 150-200k+, I'd consider a set of valvesprings while it's out. Certainly not required, but they do get a little soft after a while.

Otherwise nothing else comes to mind. Let me know how it goes. I've swapped a Monte Carlo years ago, but I'll be doing my 87 K20 Suburban in the next year or so and am starting the parts planning.
 

TotalyHucked

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^Good points as well. I've got an OE replacement '85 big block rad in my truck with a Tejas Steelworks shroud and duel 13" Spal fans. I've seen several guys use the OE LS mechanical fan and shroud with success though, just depends on how much room you have. I also agree about the valve springs at the very least. If it's higher mileage, me personally would tear it down for fresh gaskets and to inspect bearings at least. If it's low mileage and you trust the guy, throw some springs in and run it.
 

Camar068

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10 yrs Air Force
where's your VSS signal coming from? Mine isn't manual so I've not read the options on that.
 

Bextreme04

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where's your VSS signal coming from? Mine isn't manual so I've not read the options on that.
That was going to be my comment as well. You will need to have a manual trans segment swapped in to the stock PCM and will need a VSS signal from the transfer case if you don't want issue with idle and other things when you push the clutch in while driving or are in 4Lo
 

Camar068

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That was going to be my comment as well. You will need to have a manual trans segment swapped in to the stock PCM and will need a VSS signal from the transfer case if you don't want issue with idle and other things when you push the clutch in while driving or are in 4Lo
doesn't have to be in the TC, it can be on the output shaft of the trans or even on the output of the transmission or the other end of the drive shaft.

Not sure which way will be the best bang for buck on a manual though.
 

Bextreme04

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doesn't have to be in the TC, it can be on the output shaft of the trans or even on the output of the transmission or the other end of the drive shaft.

Not sure which way will be the best bang for buck on a manual though.
In this case it absolutely does. He only has one spot to pick a VSS signal from, because it is a manual 4wd, the speedometer drive is only on the transfer case. It is cheap and easy to get a pass through gm vss driver that will provide enough of a vss signal to the ecu to allow it to function properly. If he was swapping in a newer electronic automatic, then he could choose to get the vss signal from the oss of the trans too, but not on an SM465
 

iamtherealJayy

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We’ll all of this is unknown news I didn’t think about, maybe this is going to take longer than expected. I don’t have the engine yet so I’m not sure if it’s return style or not, but I got plenty of fuel line if it is. As for exhaust I’m just planning on running stock manifolds that come out somewhere I have access to a welder and I plan on trying to connect to existing exhaust system eventuslly but I’m fine with running some straight pipes for a little while. I planned on retaining the fan on the 5.3l if possible so I don’t have to do any extra wiring. This is news about the vss I haven’t read anything about that or know anything about it. I know the guy building my harness and doing the vats removal asked what trans I was running. So how would I go about using the speed from the transfer case? Out of everythint I’ve read and watched I don’t know how I missed that? As for radiator mine is brand new almost a year old so I plan on keeping it but I figure I’ll have to upgrade to the ls upper rad hose. And what’s this I’m hearing about steam ports? Do they all have this or certain years or?
 

iamtherealJayy

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This is what all is being done to the harness, does it check out?
 

Hunter79764

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FWIW, I've run mine with a TH350 with and without a VSS and have not noticed much difference on my Monte Carlo swap. It is entirely possible I'm leaving some MPG on the table, I get about 19 everywhere with DEEP highway gears and a stock engine, I never got a good reading on MPG with a VSS operational, but drivability is fine.
You will want to add an OBDII port to wire up. Grab one from a junkyard for a couple dollars, it's worth having if no other reason than convincing the AutoZone employee to come read the codes on your squarebody... But seriously, you do want it for future diagnostics etc.
 

iamtherealJayy

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I do 100% plan on having on board diagnostics, but I’m dead honest when I say I had no idea about the vss being important on a manual, I’ve googled and found a couple for $300 so I’m thinking I may go ahead and ignore it if it runs. If it won’t run then it’ll be an issue for then. But can someone answer my question about steamport? I’ve read some people mention not to forget it and attach it into upper rad hose and others haven’t mentioned it. Is it year specific or car/teuck specific?
 

iamtherealJayy

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Can I get the Dakota digital adapter for the vss so I can retain my factory speedometer?(not properly working but want to keep so I can eventually fix) the adapter thing is around $50 I’m willing to spend that but I really don’t want to spend a few hundred bucks on this I thought the manual trans would be easier
Edit: this thing “Dakota Digital GM-Thread Pass-Through Pulse Generator 8K 2-Wire SEN-01-4160”
 

Camar068

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noticed your other post about the NP208. I have a 5.3/4l60e/NP208 combo. For the VSS signal, I drilled and tapped a hole in the adapter between the transmission and transfer case. I then put a reluctor wheel on the output shaft at the location of the hole.

Yours is manual right? Whats the model on the transmission?
 

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