Re: LS engine swap info
 

You don't need to, but it couldn't hurt to put a little on them

Re: LS engine swap info
 

I don't unless its an aluminum block.

Re: LS engine swap info
 

There are a few links that have since expired or are dead at the beginning of this thread. Also, many pictures are linked to "free" hosting accounts that require the hosting person to sign up for third party hosting. Can anyone please provide the vacuum check valve fitting for the brake booster? The fitting I have for the LS motor is larger than the barbed check valve on the existing booster.

Also, does the coil power feed provide 12v while cranking on a stock 67 engine harness? Wiring diagrams are not very clear. I have my LS installed and it cranks but will not fire. I have fuel pressure, VATS was disabled and base tune loaded. Data logging while cranking doesn't show much.

Re: LS engine swap info
 

Scotts,
I'm not clear on the question referencing a '67 harness. If using an LS motor, are you not using an LS harness/PCM? If so, are they the ones that originally came with that motor?

Coil packs should be getting voltage while cranking.
Also, if the motor was sitting for a long time, it would be worth checking and cleaning the injectors. I doubt they would cause a non-fire situation but clean injectors will definitely help it run better.

Re: LS engine swap info
 

Thanks for the help!

I have a LS harness but it needs a 12V switched from the truck. I tied the switched 12 volt into the old 67 engine harness using the old coil wire but not sure if its powered during cranking.

The motor/trans/PCM and harness was pulled from a 04 Avalanche. It was running when pulled a couple months ago. Followed LT1swap for harness modification and was able to test fire it before installing it.

Re: LS engine swap info
 

As a permanent solution, it would probably be better to build a stand alone harness/fuse block for powering up the PCM-that way you are not relying on any potential issues with the existing '67 harness. Here is a link to the page on the lt1 site. Near the bottom of the page it shows the fuse block that gets key hot/battery hot power to run the PCM independently of anything else.

http://lt1swap.com/2000harness.htm

As a temporary measure, you can locate the pcm, fuel pump, and coil wires and connect them to a key hot or battery hot circuit. Then tap a direct, heavy wire from the battery to the starter to kick it over. You may also want to temporarily bypass the pcm controller for the fuel pump, and just feed a key hot line to the fuel pump. The pcm will only allow the fuel pump to run for a couple seconds without sensing the engine cranking over. Even if the engine is cranking, you are not certain that the PCM is sensing it if all sensors are not hooked up properly. I try to remove as many variables as possible until you can pinpoint the problem.

Re: LS engine swap info
 

Definitely check and clean the injectors. I experienced the same no fire issue with an engine that had set for a good while. Had power every where I needed and the coils where firing when they should. Ended up pulling all 8 injectors and ALL of them where stuck. Cleaned them and made a harness to cycle each one with a drill battery to make sure they clicked open and closed before reinstalling them. Put them all back in and the truck fired up the first crank...To clean mine, I pulled them out, pulled the o-rings off and soaked them in a pan of berrymans carb cleaner over night. I had to tap most of them on a hard surface to get them to cycle while applying 12 volts. I also sprayed brake clean in each one with it held open with the battery and blew thru each one to get all the gunk cleaned out of them.

As for the 12v coil wire, it should have power while cranking. Make sure it is not a resistance wire or has a resistor inline. This wire needs to be a full 12v for the PCM. That is how I have my '65 wired, I just replaced the coil wire with a regular 16 ga wire from the plug on the firewall all the way to the PCM.

If you followed the lt1swap.com rework, then you should have already made the relay/fuse block that tlorber talks about.

Re: LS engine swap info
 

Thanks all. I did end up checking the coil wire and it was hot during cranking. There was 2 issues (of course, 100% was me rushing and missed things). The crank position sensor was only lightly pushed into it connector. I had set it there a week or so back and thought, "I will pull the starter later to plug that in". Being hidden, I completely missed it.

The other issue was the Holley returnless in tank pump was wired in reverse. When I tested the fuel system before installing the motor, it worked great. All lines pressured up to 60psi, no leaks... When I installed the connector and wired the relay for its final install, I reversed the leads. I heard the fuel pump kick on so I thought it was fine when I was trouble shooting. I was going to pull the injectors and noticed that the fuels didn't release any pressure. That's what tipped me off.

Anyone know the brake booster check valve part number? The hose is larger on the intake that the original hose to the stock booster.

Re: LS engine swap info
 

For the Check Valve, try Dorman 80190 or 80189. One of them comes with new grommets.

Re: LS engine swap info
 

Here's some good reading.
http://www.chevyhardcore.com/tech-st...kyard-ls-swap/
http://www.enginelabs.com/engine-tec...ags-to-riches/
http://www.superchevy.com/how-to/eng...to-ls-engines/

Re: LS engine swap info
 

It might already be in this thread, or another, but I'm trying to find a junkyard shopping list. Trying to see what is the best donor vehicles for harvesting parts.
Also, I'm in no rush and I want to make finding the cheapest parts part of the hobby.
I actually love browsing and picking parts at junkyards.
But because I live out in the country on property, I have the space, so I think the biggest savings would be buying a donor that has the most usable parts. So what is the best donor for the harvesting the most usable parts that'll work for an ls swap into the 63-87 generation trucks?

Re: LS engine swap info
 

I would look for any LS powered GM pickup or Suburban/Tahoe type vehicles. Look for lower mileage, but don't be afraid of a 200k mile complete running vehicle. You can use a ton of items for the swap. One I did I bought a complete running/driving wrecked 2000 GMC Seirra for $800. I used the engine, accessories, PCM, transmission, wire harness, throttle cable, trans cooler lines, radiator, I kept the cruise module to hook up later, and quite a few other small pieces. Once I sold what was left of the truck, I only had $400 in what I kept. I used the engine as is, did the harness work myself, sent the PCM off to the guy at lt1swap.com. Trans was slipping so I had it rebuilt. Looking back, I should have kept the BCM, the headlight switch, the instrument cluster, the fuel lines, and the fuel pump and sending unit. All those parts could be used to make other things work in an old truck.

Re: LS engine swap info
 

Man, if you can get ahold of an entire vehicle, like aggie91 did, you'll be so much better off. But if not the whole vehicle, I recommend trying to get everything (engine, trans, wiring harness, pedal, pcm) off the same vehicle if you can. Also, I personally like the pre AFM models, which is 06 and older, I think.

Re: LS engine swap info
 

Thanks guys.
Yes, I'll be keeping my eyes out for a full donor.

Re: LS engine swap info
 

Best option at this time, money and time wise is a 2012 and down to a 2005. 13 and up have VVT and DOD mostly. Also, 2014 and up are LT’s and not an LS. Whole different animal that has different challenges.
DBw swaps are nice because you can set up cruise fairly easy.

Good luck!!

Re: LS engine swap info
 

There is something to consider if you get a whole truck. I'm pulling the 6.0 and trans from an 03 K2500 right now. I spent the whole weekend and still don't have it out. What an SOB to pull everything. They knitted the power train together with all the wiring and plumbing. Everything that runs to one thing is routed through and restrained to 3 other parts of the vehicle. You can't pull the engine and trans together unless you pull the front diff. The exhaust is in the way of everything. You have to pull the intake to get enough clearance to lift the engine and be able to get at the top bell housing bolt. A 2WD would be a bit easier. If I did this again I'd pull the body off first. It would be easier.

Re: LS engine swap info
 

I'll be looking for a 2wd.
Thanks, I wondered how much of a tangled mess it would be.
I did figure I'd remove the body first.

Re: LS engine swap info
 

Next time just jack up the front of the body and block it up with 2x4's if it's a suburban or lift up the cab if it's a truck. 90's dodge dakota's with the v8 were terrible until you jack up the cab. You can actually beat flat rate times.

Another trick i do with s10 blazers with the 4.3/700 r4 was when all of the bell housing bolts and converter bolts are removed and you are ready to pull the motor. remove the trans mount bolts (2 bolts) and pry the trans rearward all the way rearward until the threaded bolt holes in the mount become visible and just thread a bolt in the hole to prevent the trans from drifting forward. Now just lift the motor straight up and off the motor mounts. The flywheel just touches the face of the bell housing as it goes by. This makes a miserable job very easy, no need to move the front diff around, no prying and tugging on anything, just lift and separate (like a good bra)!!

Re: LS engine swap info
 

Spoken like a true Yooper.

Re: LS engine swap info
 

I harvested my 6.0 from an Isuzu NPR..Tilt body forward Remove engine.. And it came with an F-body oil pan and manifolds.

Re: LS engine swap info
 

Does anyone know what exhaust manifolds will fit a s10 with a ls1 motor?

Re: LS engine swap info
 

I bought my headers from Classic Performance Products in Placentia, CA. I did not have any clearance issues with the frame. However, I did push out my inner fenders (by about 4" on each side) in order to give better clearance between them and the engine, headers, etc. If you check my thread there is a picture of the headers on post #17, and some pics of the metal work on the inner fenders later in the thread.

Re: LS engine swap info
 

Looking for help and PICS of coolant set ups. I have a 5.3 going into a 69 c10. Found an aluminum rad. With port for steam vent. What do I need or HAVE to use... (overflow)...or what is possible as the simplest
option? I am running a manual fan in original shroud. The red. has the outlet under cap. as well. Wondering what is simplest set up.

Re: LS engine swap info
 

I had a radiator guy braze a steam port bung near the top of the radiator tank (1/4 " tube). The steam line goes from the heads to the bung via a rubber tube. The picture attached is not mine, but it shows the tube along the main radiator feed. As long as the steam port is near the top of the cooling system, you're fine.
Attachment 1766092

Re: LS engine swap info
 

I guess my question is so I have to use the LS OEM pressurized tank I got with engine?

Heater lines to heater core - check
Radiator in/out - check
Steam port to rad. - check

All that's left is small tube at alum. radiator neck. Old school overflow set up to this?

Re: LS engine swap info
 

You can use the original tank, or you can just have an old school remote overflow tank, as long as you have a radiator cap that will hold pressure prior to the overflow tube. Below is a picture of my spout (at the top of the pic) and the puke tank.

Attachment 1766105

Attachment 1766106

Re: LS engine swap info
 

Thanks for replies.

Now a question about wiring....so I received my reworked harness...not impressed but it's done....could someone guide me as to which wires on my 69 c10's harness I need to splice into? With starter wire this is a 4 wire harness for 5.3.

Re: LS engine swap info
 

Reliable place to send ECM to verify proper things deleted/bypassed?

Re: LS engine swap info
 

If you're just looking for a standard mail order tune with nothing fancy but will get you up and running, lt1swap.com is hard to beat. Cheap and reliable.

Re: LS engine swap info
 

Thanks Nova...

Hopefully he'll be able to tell me what ECM is looking for for VSS senor? Dakota Digital said that was crucial before ordering the VSS sensor from them.

Re: LS engine swap info
 

you've already been told WHAT to order

Re: LS engine swap info
 

Dakota digital asked me what the ecm pulse reading is i think...128 or something different. I am not sure and ecm doesn't have any labeling on it. I sent lt1swap an email to ask about bad sensor reading from ecm.

Re: LS engine swap info
 

The ECM is looking for 40 pulses per driveshaft revolution(this is tens of thousands of pulses per mile), but it uses some math to determine how many pulses per mile that is since it changes with gear ratio/tire size. This is adjustable in tuning software.

The ECM can output a vehicle speed signal on one of two wires, one sends 4000 pulses per mile, usually used for speedometers/cruise, the otther 128k pulses per mile, used for ABS and traction control.

You need to know your rear end gearing and tire size to make the calculations you need. Is your current speedo gear in the trans giving you a correct speed reading on the speedo?

Re: LS engine swap info
 

I am running a TH350 behind the 5.3...no ABS, traction, or cruise. No modifications to engine, just stock DBC set up.

I will look at rear end for code to see what I have. Truck has never been running while in my possesion, so no idea if current Speedo gear in trans. is being translated into correct speed. It is a fresh rebuild.

I decided to run a VSS sensor instead of hoping I had no issues w/o it. I am sending ECM to lt1swap to be sure it is done properly. On his site he mentions tire size and gear ratio doesn't matter if I'm running a TH350. As stated before, Dakota Digital asked me what signal was from ECM...128K or something else. I told him I have no idea and didn't say how I can find out. So I am hoping lt1swap can tell me when he gets ECM so I can order correct sensor. Or can anyone reassure me of what part will work with flashed ECM from lt1swap?

Re: LS engine swap info
 

Just kind of wandered into this 275 post thread so forgive me if I don't have all the context, but from what I've gathered:

You have an ECM that needs a speed signal sensor. You have a TH350 trans that does not provide a digital speed signal.

So you're adding a VSS sensor that will provide the ECM with a pulsed signal. The ECM and the sender need to agree on how many pulses per revolution. Normally for a GM auto transmission it is 40 pulses per rev.

If, for whatever reason, the speed sensor you wind up using is a different number of pulses per revolution, you can change it in the LS3 computer if you have HPTuners or similar. Odds are you're going to have to edit it to change tire size and gear ratio anyway.

For example I bought the "automatic" LS3 that comes set up for 40 pulses per rev but then put it in front of a TKO-600 trans that is (I think) 17 pulses per mile so changed it in the ECM before I ever installed it.

Re: LS engine swap info
 

The pulse generator from your other thread should be able to be made work, just need to get a vague idea of pulses per rev and pulses per mile. Don't need to be accurate just someplace sane, the things the engine relys on vehicle speed for dont need very high accuracy. It may even be able to work without it completely, out of all the swaps I've done harnesses for no one has ever wanted to stick with the old 3 speed, they wanted the new transmission almost as much as the ls.

The guys at lt1swap should know for sure, and be able to help you get it set up which ever way you need.

Re: LS engine swap info
 

He emailed me back yesterday...i think i got it sorted out. Hopefully just a week away from first ride to alignment and muffler shop!

Re: LS engine swap info
 

Just reviving my old thread. I may be getting back into a Blazer and looking at all my options!

Re: LS engine swap info
 

thealien, THANK YOU and the others that have contributed to this thread, tons of great info here.. :metal: