I have just bought a newer Envoy that was wrecked to use its drive train in my project Nova. I have scoured the net looking for info on the swap, and have come up short with a few answers.

The biggest hurdle I have come up with is finding someone to reprogram the computer to shut down VATS and some other not needed accesories, I would also like to find somebody to rework the wiring harness to clean up the swap.

I plan on using everything I can from this donor truck, including the transmission.

Any suggestions would be appreciated


bonuts

You can contact EFI-DIY on here, he also offers a rear sump engine swap oil pan for those engines.

Good to see another 4200 finding a proper home. FYI I'm in Calgary.

I think you have come to the right place. Efi-diy has been waiting for you. Please post your progress here because there is growing interest here for the 4200s.

Beater

Check out PCMforless.com for your tune. Or if you have a 2006, I can do it for you for the price of the HPT credits. If you are using the 4L60E there is virtually no cleanup of the harness. Run the pink wires to ignition, black to ground, and hook up a fuel pump.
I have a pretty well documented swap here:
http://forums.trailvoy.com/showthread.php?t=51636

Limequat I read all 29 pages of your swap, very impressed. The donor vehicle is a 2003 and I plan on using the 4L60e, I would rather run a standard but for a few reasons I won't be yet and I'm sure my Muncie M22 won't be easy to mate up.

As for the tune, can somebody explain these to me? I planned on just sending mine away, getting rid of VATS and emmission stuff, and that being the end of it. I plan on running it stock for now, maybe a turbo later on.


bonuts

Thanks!



It's just that easy. PCMforless has a sheet that you fill out for specifics. You'll tell them which equipment you want to delete and they'll send you back your PCM.

Now, going turbo will be more complicated. You may need to upgrade to a MY06 PCM for that.

Thanks Limequat, like I said I am not good with the newer vehicles, so now I have to figure out what I need and what I don't need as far as the computer rework goes.

I am not going to be able to do the swap right away I am just doing the research now. I am building a '67 nova so my swap will not happen right away, old cars (or the ones I get) need lots of other work... this one needs the firewall fixed and a Mustang II front clip installed. I have all the stuff to get it ready so hopefully in the next month or so I will start adding the powertrain.


bonuts

Hey bonuts! I am doing a similar swap of an '08-'09 Vortec 4200 (a.k.a. Atlas LL8) and planning on turbocharging it to install in my '71 Nova. I wish I had a '67 to put it in (since they're small and lighter), but any Nova will work as long as its made before '73! I'm still trying to track down an '08 or preferably '09 trailblazer/envoy or plain motor so I can begin my project too! It's such a bitchin' motor I can't wait to get started to see what it can do! How much did you buy the wrecked envoy if you don't mind me asking? I think I'll end up having to go that route instead of buying a crate motor unfortunately...

hey De-Gee', check out http://www.car-part.com in your hunt.

What would be the problem with swapping the LL8 into a '75-'79 Nova? The only architecture changes in the later cars I can think of was in the steering linkage.
I'm the early stages of planning my next project and a Atlas-powered '77 Nova is on the list.

Previous project:http://www.hemmings.com/mus/stories/2010/08/01/hmn_feature6.html

You will need a rear sump oil pan and fabricate mounts.

emtech motorsports sell a cast pan

That was expected. It was the claim that the Atlas motor wouldn't fit a Nova later than '73 that had me puzzled.

It'll fit just fine. I'm using a '78 nova clip in my 51 gmc

I have taken most of the donor truck apart and am days from removing the engine/trans from the truck. Before I take it out I have to figure out exactly what computer components I need to salvage and find out where they are located in the truck.

Like i've said I am completely new to computer controlled engines, so this is all new to me.

Progress is being made and hopefully I can get the drive train into garage before the snow falls and get this Nova running


bonuts

The harness are fastened to the back of the fender mounted fuse box.

Basically if its attached to the mainifold mounted pcm with a harness - you need it.

If you have time undo the harness that goes through the firewall from the fuse box and runs inside the vehicle. Then remove the entire inside harness(you'll only end up using parts of it, but its really high quality wiring - good for later use). Also get the gas pedal assembly & dash (incase you want to use it).

Anything else - strip & sell.

Excellent help. Does anybody have a write up, or explanation how the drive by wire throttle pedal assembly works? I get the general idea but would like to know more to clarify a few things.

I will salvage the harness that runs into the truck, just out of curiousity what would I use from that harness?


bonuts

Excellent help. Does anybody have a write up, or explanation how the drive by wire throttle pedal assembly works? I get the general idea but would like to know more to clarify a few things.
Best source is the GM manual.


I will salvage the harness that runs into the truck, just out of curiousity what would I use from that harness?

Wiring to the throttle pedal assembly & dash. Also A/C demand input, Cruise control etc...

Note I think that the cruise function is built into the PCM, all you need is the switch on the collum and brake input.

They're just foot operated angle sensors. Pretty sure the TBs are resistive elements, could be Hall or inductive, though. It's not important. All you need to know is which 6 wires to grab.

You don't need the entire electrical center, but if you save the fuel pump relay and cooling fan relay it could save you some headaches.
Whenever I find myself in the position, I'll save every harness and relay I can get my hands on. The stuff can prove invaluable, even if you can't forsee a use in the short term. Why buy wire when there enough under the hood of any old junker to fuel 3 motor swaps?

[quote=limequat
You don't need the entire electrical center, but if you save the fuel pump relay and cooling fan relay it could save you some headaches.
[/quote]

True, however, if you keep the electrical center (fuse/relay box) and remove the unwanted/un-needed relays/wires it keeps the install really tidy. All the wires enter/exit (except the power feed) via gang plugs. The wire terminals lock into the gang plug and can be removed by depressing the terminal retainer lock.

The engine is ready to pull out and I have salvaged all the wiring harness from inside the truck. I think I have everything I will need and all the worries about the throttle assembly was for nothing, pretty sure that will be the least of my problems.

To cut down on this wiring nightmare I have, can I hack off anything that goes behind the shifter? There is a whole other fuse box/electrical center that I believe has nothing to do with the engine running or anything else I may need.

I may have taken a bigger project than I thought, all this wiring is pretty intimidating. I will need to find or buy a wiring diagram for this truck and start cleaning up the harness.

efi-diy now I'm off to your neck of the woods for my sons hockey tournement, great weather for a road trip!


bonuts

:(- -20*C tonight and more snow - it sucks.

Your welcome to stop by tomorrow if you have time.

The wiring was the turning point for me. to put it in my '58 it was overwhelming, I removed everything from the donor including ABS which was going to lead to a brake swap, the fuel system which was going to need special lines and tank for the wagon style body, and all the various other sundry wires and boxes which I had no idea of their use or function, so I went for a blown 292 which I can sorta undrstand and don't need an electical engineer to repair, but then I still like distibutors and carbs.

EFI, would liked to have seen your rig, just no time kids had 2 games a day and the girls had to see the new mall... Didn't even have time to talk my engine builder about my race cars build.

Jalopy I definately get what your saying and I have a few small blocks that would be far easier to put in my Nova but I'm in no rush for this car to be ready, it will be a few years and wanted to make a better daily driver thats decent on gas.


bonuts