Introduction

Okay everyone, now that I have a good understanding of what the 3800 SC -- W-body swap takes, I am going to make an attempt to let all you thinkers and doers understand it too. This page will detail everything I have had to do to get the 3800 SC functioning in my car. The thing I wished that I had most during my swap is some experienced help because this is a rare and difficult task, so I am going to try to make this a valuable resource for you. My advice is to make a list and give it to whoever you are going to get the engine from. So here it goes...

Ingredients

3800 Supercharged Series II L67 VIN "1" engine --------------------------------- available in 1997 to present Pontiac Grand Prix GTP, Buick Park Avenue Ultra, Pontiac  Bonneville SSEi, and Buick Regal GS.

4T65-E Transaxle ---------------------------------------------------------------------------------- you can use another transmission however this is the only one that can both handle the power and mate up perfectly.

All engine sensors and accessories-------------------------------------------------------the salvage yard tried to gyp me on the power steering pump, alternator, starter, and even the plastic engine cover. Usually the factory A/C compressor will work.  Be sure to say you are doing a swap! Also don't let 'em forget about the exhaust header and both O2 sensors!

Axle shafts and hubs-----------------------------------------------------------------------------they fit perfect in my car, you should not need the knuckle, just the front hub assemblies. The axle shafts will probably fit in the stock hubs but they do not mate together properly and you will ruin the hubs.

Powertrain Control Module (PCM)---------------------------------------------------------this may have codes in it that need to be cleared by someone with a tech-II.

Complete wire harness--------------------------------------------------------------------------be sure to get an engine wire harness along with an interior wire harness, it is too much to try to modify your factory internal harness!

Body Control Module-----------------------------------------------------------------------------this is a fairly small black box that mounts under the driver side kick panel. It controls door locks, lights, and the antitheft system. It also sends a fuel enable signal to the PCM.

Engine fuse block---------------------------------------------------------------------------------Make sure this has all fuses and relays.

Coolant reservior tank

Intake air box

Exhaust flange-------------------------------------------------------------------------------------this is the flange that tightens the exhaust pipe on to the header output.

Transaxle mount bracket

Battery

Battery power and ground cables

Radiator Hoses

Cruise control module-------------------------------------------------------------------------check to see if you need this or if you already have a newer one.

Accelerator and Cruise cables

 

Instructions

Installing the engine is actually the easiest and most straight forward part to this project. The first thing is to make sure you get the old engine out (obviously), make sure you remove your radiator and fans so you dont ruin them. Remove the battery and all wiring from the car. Remove the dog bone mounts and brackets along with the braces that connect to the strut towers for clearance. Pull off the front wheels and hub assemblies to be able to remove the axleshafts. Disconnect all mounts and any other devices connected to the car. Pull the engine and transaxle assembly out of the top of the engine compartment some people say dropping the whole thing at the subframe is the easiest way... its not unless you dont have a hoist! Your car should now look something like this. The 3800 SC and tranny should drop in and bolt up to stock 2.8/3.1 engine mounts although i did have to move my dog bone mounts about an inch to the passenger side of the car to keep them out of a bind. Once the engine is sitting in it should look like this. You've now finished the most meaningful part but definitely the easiest. Now its time for...

Customizing. The first thing is to relocate the battery to the other side of the engine compartment or where ever you see fit. I had to cut and hammer on the engine compartment wall like to get my battery to fit properly. I also cut out a hole where my intake runs like so I can do RAM air in the future. That is the only customizing necessary to do to your car. Now you can replace your radiator and fans and hook up your trans cooler lines. On my car I wanted to add a transcooler in front of the radiator so I customized the lines like using hose clamps and my old cooler lines. I also had to make a modification to the piece of plastic that holds the top of the radiator in postion so that I could fit my wire harness across it in the intended, GTP,  position. Now it's time to run new fuel lines from the rail on the engine to the two metal lines coming from your fuel tank. I was going for looks (and to drive it at the track) so I went with two 3 foot long steel braided lines and used cool looking, but standard hose clamps. I was worried that there would be too much pressure for standard clamps but I was told they held up to 200 psi when tightened properly and the fuel system only goes up to about 54 psi. Be sure to note the sizes of the fuel lines and match them accordingly to the lines on the rail. Another modification I did was to slightly flare out the metal fuel lines, with a special flare tool, to be sure the hose was on tight. It can be very difficult to push these hoses over flared lines so dont flare too much! Once done it should look something like. Now on to the power steering pump lines, these are pretty easy to do, just cut the rubber hose and clamp it on to the correct tube on the pump, then cut the metal line and run it up. You will need to purchase about 6 feet of heater hose and just clamp it down in the proper location. Be sure to: 1. remove all old heater hoses/lines and 2. note which line goes to which pipe. The only other thing to customize is a location for the fuse block. I placed mine in the fender behind the battery but you can get a coolant tank that sits down low like in the 1999 GTP so that you can place the block on the strut tower, like its supposed to be, if you have clearance. Now you are pretty much done with customization and are ready to continue...

Hooking it up. Now, there are two lines from your existing engine that need to be connected to the new one: the first is an evaporative emissions (EVAP) fuel line, the other is a vacuum line. Now you can connect your upper and lower radiator hoses. Next connect the accelerator and cruise cables from the supercharged car. You obviously only need the cruise cable if you are replacing the cruise control module. Now you can go ahead and install your new axle shafts and get your car back on the ground (actually you could have done it before but it fit best in the "hooking it up section" sorry). If it doesn't get in the way you can hook up the coolant reservoir now. If you have an exhaust ready to go on or if you need to get one on, then tow your car to get it on now as it is a bad idea to run these engines without an exhaust system, there is a tiny slight chance of warping the valves especially on cold days. Go ahead and hook up anything else you disconnected or that wont get in your way as you are...

Wiring the engine. First of all we are going to do the easy part of the wiring: the engine harness. The piece of plastic will sit on top of the radiator like this as long as you modified it like I specified before. Now you are ready to start hooking all of the sensors up along with the starter and PCM, although I would recommend not actually plugging the PCM in until you feel ready to start the car as you can burn it out! By the way the PCM goes where the battery used to go, you should probably make a bracket to bolt it down and use rubber stoppers to keep it from "jiggling" around. Now you can hook up the battery, find a good ground for the negative cable and then connect the hot cable. The hot cable should first be connected to the starter as shown, then to the fuse block post. Do not connect the hot end to the battery yet! At this point you should double check that all connectors are connected and all wires are isolated as to avoid shorts. Also make sure the engine is properly grounded to the body like. Now you can connect the engine harness pigtail into the fuse block and get ready for the most difficult task of all...

Wiring the interior! Step 1: Rip out your entire dash! Well, you dont exactly want to rip it out but you will need to remove everything except the steering column (unless you got a new one from the supercharged car), and heater core type junk. Now take your new internal wire harness and place it in its approximate position like this and you can run it out where your old harness went through the firewall and plug it into the engine fuse block on the passenger side of the car. Also you can plug in the 3 or 4 connectors on the other end of the harness by shoving them through existing holes in the firewall. They plug into the engine harness and and cruise control module. Now your done, drive off into the sunset. No, your not that was a lie, its just starting to get hard. Go ahead and locate all of your grounds and ground them. Some advice is to use a multimeter to double check continuity in all of your connections. Now you should be able to plug the steering column harness in or install the steering column if you are doing it that way. *If you are using your old column be sure to rewire it properly or you will burn stuff out!* Connect the hot terminal up on the battery as you watch and listen for shorts, blown fuses, fires, or explosions. If any of these occur then you hooked something up wrong or have wires touching somewhere. If nothing happens then good, plug in your PCM and BCM inside the car. Also you have to connect the fuel tank unit up: this is a thick grey wire that goes from the internal harness through you cars body harness. Once you have all of this hooked up you should be able to turn the car over and even start it, however it will probably only run for about 5 seconds. If it keeps running then I hate you but you just have to put your interior back together. Now the reason the car dies is a simple, non detrimental one: you see the BCM checks all of the antitheft system components. These systems send a digital or serial data signal to the BCM. When the BCM receives these signals it sends a digital signal to the PCM and lets it know that it is okay to let the car continue to run. Well, because these signals are digital, they cannot be faked, you have to either hook up the antitheft system or bypass it. There are about three different types of antitheft systems available in 3800 Seires II Supercharged cars: PASSlock, PASSkey, and Content Theft Deterrent. My car has Content Theft Deterrent which shuts down the fuel pump, so I simply ran a generic ignition wire to my fuel pump and my car worked. PASSkey, I believe, shuts down the starter and PASSlock shuts down the fuel pump like Content Theft Deterrent. Although the BCM, PCM and antitheft system communicates with digital signal, the fuel pump and/or starter do not, so a simple power wire should do the trick. If the car still dies after 5 seconds then you may need to reset your PCM, reset your BCM, or program your BCM and antitheft system. To learn how to do this see the wire diagrams I have scanned in for you. Another thing: PASSlock, and PASSkey use separate modules that you have to buy and hook up if you are going to install the antitheft system. Your car should need nothing else to stay running, if it does then contact me and I'll try to help. Once it is running you can then put your dash back together, easier than it sounds. If your dash instruments are anything like mine then you have to completely rewire them all. This is difficult and tedious but it can be done. Keep in mind that many connectors, like heads up display, keyless entry, and air bags may not even be used. I am not going to go into the specifics of how each control panel should be wired but, once again, if you need help contact me. You can also use what I used: these are scans of all the wire diagrams I used to get my car running; however, they are for a 1998 GTP and 1991 Lumina and may differ from the wiring of other cars. But you can go to your local big library and copy all of it out of a Mitchell manual. When you finish hooking all of this up you can put your interior back together and marvel over the feat you have accomplished. That's the only thing that kept me going...knowing how much I was going to love it!

 

Conclusion

If you have any questions at all that I have not answered, or if you can think of something that I forgot to put on this page, please don't hesitate to CONTACT ME! Also, If you hook stuff up wrong and blow something out don't blame me, I'm just here to help. As you are wiring everything up be sure to always check fuses and double check everything you do, a simple mistake can keep your car from running. Good luck and let me know about ya!