5.3L LS checklist with part numbers

To hook up your temp gauge, you can use a 3 wire sender that screws into one of the heads. For my truck I used a 1998 Camaro. Using the 3 wire eliminates having to use 2 sendors.....one for your truck gauge and another for the LS. ACDelco p# 12551708.....hard to find so they'll cross reference it to another manufacturer such as Standard Motor Products TX111.

I'm currently putting my LS back together and busted the ACDelco sender....so Oreillys will have one tomorrow (TX111).

Do some research to verify that your gauge will read correctly with the camaro sender.

Build pages to look through (mine and Dougberts).

Dougbert

Camar068

iamtherealJayy said:

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?

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Yes don't forget to do that. With you being in TN, I would bypass where it runs through the throttle body. They run it through the throttle body to help warm it up when it's wicked cold.

I'm using my original 86 k10 radiator. I took it to a radiator shop and had them add a port just below the radiator cap. cost was about $20

A lot of folks "T" into the radiator hose, but to me that's just adding another spot to fail....on a critical component.

lol gonna continue to flood you with info as I think of it....

You will probably need to get an adapter for your oil pressure sender. You'll install the adapter in the block, then install your trucks original OIL PRESSURE sender into it. Seeing as how you're big on ICT.....link below. Top-rear or side mount.

ICT oil pressure sender adapter

Yes I want to get rid of the 203 in my 76, but this truck is currently a 350 sm465 np205 truck going to 5.3 sm465 np205. Ive been talking to the guy doing the tuning work and he thinks he’s got it he said I’m the first manual one he’s had to do all he’s done is automatics. I planned on running the factory temp sensor to the passenger side head with a resistor? I believe, in the line to get the temp reading, as for oil pressure I’ve got the adapter for both oil and temp already ordered. What’s the purpose of the steam port? Is it needed? Is it obvious where it’s at?

iamtherealJayy said:

Yes I want to get rid of the 203 in my 76, but this truck is currently a 350 sm465 np205 truck going to 5.3 sm465 np205. Ive been talking to the guy doing the tuning work and he thinks he’s got it he said I’m the first manual one he’s had to do all he’s done is automatics. I planned on running the factory temp sensor to the passenger side head with a resistor? I believe, in the line to get the temp reading, as for oil pressure I’ve got the adapter for both oil and temp already ordered. What’s the purpose of the steam port? Is it needed? Is it obvious where it’s at?

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worth reading.....google is your friend. I'm not saying you need the steam vent kit at the link below, but this explains a few of things about the lines.

Why Steam Port

After some reading I know a basic of what it is I just need to figure out how I want to go about it. I don’t know if I mentioned but my engine is a return style fuel rail.

iamtherealJayy said:

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”

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Yes, that was the part I was talking about to just get you a pass through signal. You need it on the manual compared to the “non electronic automatic” like a TH350 to make sure that it handles idle conditions properly when driving and pushing in the clutch. There aren’t many reasonable options when using a np205. You can send the tail housing out to ORD and they will machine it for a VSS and provide the correct tone wheel, or you can use a good sensor like the sen-128, but then you lose the mechanical Speedo. Best bet for you is to use the pass-through. Let your tuner know that it will be an 8k signal and he can set that in the tune. It likely wont read correctly, but it doesn’t need to be exact since you are just trying to get a basic signal in to tell it whether you are moving or not.

That pass-through is what I had, then I smashed it repeatedly until it broke (lesson learned, just because it "fits, but is close" when sitting still does not mean that it keeps clearance when driving "spirited" for a while. Make sure you have plenty of clearance around it at install). Skipping it will most likely affect wither idling gas use or highway mileage, depending on how your tuner does it (I think).

Steam port connection generally is needed, it's the tube coming out from under the intake manifold and usually though the throttle body. There's plenty of options of where to tie in, if you swap a late model radiator then you should have a steam port on the rad. I installed a modern style radiator in my swap and went that route. Other folks drill and tap the water pump housing, but that seems like a risky option if you drive it often and possibly have a water pump failure on the road (you might not be set up to drill and tap a new connection in the AutoZone parking lot). I believe I've seen tee connections into either the upper radiator hose or maybe the heater hose. Yes, it's 3 extra potential leak points, but the chance of that tee itself leaking slim, and hose clamps are cheap and easy to replace on the side of the road if needed. Your call.

For future reference, that steam port connection is the high point on your engine. I typically fill the coolant through the upper radiator hose until I have coolant come out from the steam port hose. Doing that, I usually don't have issues with burping the system. Everybody has their method, probably all have a reasonable success rate. But if you block off the steam port, you have to get VERY good at burping the system, I don't recommend it.

TotalyHucked said:

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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I plumbed mine with a return line using the stock regulator. It works fine.

I recently decided on swapping mine since the 350 is starting to get tired. It is good that I ran across this right now.

@Bextreme04 id like to retain my factory speedo if at all possible, I guess I’ll run an adapter in the upper rad hose for the steam port. One thing I thought about yesterday, will I need a new throttle cable? Isn’t the ls throttle linkage on the passenger side?
@TerryRH maybe you’ll get it accomplished I’ll keep updating as I make progress, I’ve got most of the fuel system delivered still waiting on some fitting and adapters and my sending unit

iamtherealJayy said:

@Bextreme04 id like to retain my factory speedo if at all possible, I guess I’ll run an adapter in the upper rad hose for the steam port. One thing I thought about yesterday, will I need a new throttle cable? Isn’t the ls throttle linkage on the passenger side?
@TerryRH maybe you’ll get it accomplished I’ll keep updating as I make progress, I’ve got most of the fuel system delivered still waiting on some fitting and adapters and my sending unit

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Yeah, I am using the -128 sensor and a 91' electric speedometer with the trip meter so that it is easier to adjust the PCM to get the correct speedometer reading, rather than needing to adjust the drive gears to get it to read correctly.

You will need a new throttle cable. There are some retrofit options that are adjustable.. I think lokar is the go-to.

You will need to plumb the steam port to the suction side of the cooling system. The upper hose is pressurized output, not suction. Most squarebody radiators already have a nipple on them for the heater return. The LS motors have the heater feed and return right on the water pump, so you should be able to move the heater lines there and use the nipple on the return side of the radiator for the steam port outlet.

You lost me there, also I assume you meant 91”, but are you using a completely different gauge or? My speedometer doesn’t read correctly but I can tell how fast I’m going from around anout where it’s at. It starts around 100 so 0 is roughly 50 mph. I reckon I can start looking into a throttle cable, I need to figure out what the end of the cable looks like. Do you have a rough idea of how long it needs to be? I assume slightly longer than my current cable. For the steam port, I thought you wanted it to exit at the highest point possible since air rises? I have a new radiator I can look into seeing if it’s got a nipple anywhere, if not I may need you to further explain what you mean. You mean use where the heater core would usually return into the radiator under the cap with some sort of reducer ?

I'm not certain, but I assume he means a 1991 speedometer (From a Blazer/Suburban square body) swapped in, which was electronic, no cable required. Get a VSS generator from the same folks that make the pass-through VSS and then you can change the speedometer through the computer to adjust for tire sizes, gear changes, etc.

I got Dakota digital pass through vss I atleast need my odometer to function.