Potential 3800 swap

[Mattstrike]

So I've been talking with a work friend of mine. He has a late 90's early 2000's cavalier that blew the motor. He wants me to 3800 swap it, and I could use some extra cash so I figured, why not? lol.

So after looking around on the Cavi forums - looks like most people that have actually done the swap and posted details and can still be found (like 2); they used the 5-speed manual and fabbed up a subframe/mounts. Not insurmountable at all. But - this guy just had his auto trans rebuilt (not sure which one, all I know is he has a 4-banger in it) and wants to keep it. I'm thinking just grab a engine/trans/harness from any 3800 and move along, let him try to sell his trans to offset the cost of the project. But either way he's not going to go for a manual.

So there are a few things I'd need help to figure out:
-4t65 axles (which small car application do they need to come from?)
-gauge cluster. Regal harness?

The roadmap so far based on other writeups:
-Custom front corner (or front half) square tube subframe
-Custom front right lower engine mount (aka; LG3/LN3 mount)
-Slightly modified transmission mounts
-Park Avenue A/C compressor
-Speed daddy headers or similar
-W-body fuel pump
-everything else (hoses, fuel lines, etc.) is boring and easy.

I think the gauge cluster is going to be the most annoying part to figure out. Sounds like there's a chance that the '2000+ cavi uses the same data bus method to control gauges that the regal/montana uses (from the few 3400 swaps that were done). But the pre-00 probably use some unique variant of that and won't work with just a re-pin.

At least with the axles I can mix/match OEM parts at least, unlike the F40 swap I did.

Anybody here know anything about the cavi swaps? I'm thinking of leaving it bone stock L67 with a basic trans tune. Keep it simple, make it easy to R&R.

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[Mattstrike]

OK, I've been doing some research on this, and after muddling through some things I think I figured a bunch of stuff out (we'll see soon enough).

The car: 2000 Cavalier, LD9 2.4l, 4t40e.

Transmission
So the 4t40e is also used in the Grand Am, and the C/V axles are the same length between j-body and N-body, the hubs are the same, etc... Which means that the 4t65 swap for the Grand Am should be the same in the Cavi. The 99-05 N-body swaps use the following parts for axles:

LH - 99-05 GA outer joint, 99-05 GA shaft, the LH inner joint from almost any 4t65 car ever ('03 SSEI).
RH - 99-05 GM outer joint, 91 Grand Prix left 4t60e axle shaft, the RH inner joint from almost every 4t65 car ever ('03 SSEi).

Gauges
The lingo people are using is 'run the Impala program'... As far as I know the physical PCM is the same between most of the 98+ 3800 cars. So it sounds like there is a class 2 data buss that supplies the cluster in the Impala its gauge data, and it's the same data buss the 00+ Cavaliers use. So hook up the wires, flash the Impala OS on the PCM? It seems like this should be simple, is the Regal OS the same in this regard? I know the H-body swap stuff like the back of my hand, and we didn't get the cluster that runs off the data bus or whatever you want to call it until the Bonneville moved on to the g platform where I stop being interested...

The goal is to grab a donor that has the correct engine harness and PCM to minimize work on custom wiring and messing with tuning (that stuff can happen later after all the quirks are worked out). Any 3800 Impala? Regal? It would be nice to not have to touch the tune, aside from VATS delete. For now, just running it bone stock aside from headers and cold air intake.



Everything else seems to be the normal engine swap stuff. Make some motor mounts, make a new subframe extension for said motor mounts, remote mount the battery, upgrade fuel pump, connect hose thingys to other hose thingys, etc...

 

[CMNTMXR57]

DO EET!

Will it actually fit between the strut towers?

 

[boostedguy05]

There are a few of them out there.

3800 SUPERCHARGED SWAP INFO - Third Generation Forum - j-body.org - The J-Body Organization

The J-Body Organization, j-body.org, is the worlds largest automotive enthusiast group exclusively geared towards the General Motors GM J-car platform including the Chevrolet Cavalier, Pontiac Sunfire, Pontiac Sunbird, Pontiac J 2000, Oldsmobile Firenza, Buick SkyHawk and Cadillac Cimarron.

www.j-body.org

 

[Mattstrike]

There are a few of them out there.

3800 SUPERCHARGED SWAP INFO - Third Generation Forum - j-body.org - The J-Body Organization

The J-Body Organization, j-body.org, is the worlds largest automotive enthusiast group exclusively geared towards the General Motors GM J-car platform including the Chevrolet Cavalier, Pontiac Sunfire, Pontiac Sunbird, Pontiac J 2000, Oldsmobile Firenza, Buick SkyHawk and Cadillac Cimarron.

www.j-body.org

There are like 3 out there that are documented, about half of a build thread, and that info thread is a lot more musing than a real guide. I've read it, it's only half of the info and doesn't actually have the stuff about the gauges and the trans. The guys that did it were using pre-00 cars, manual swapped, which had a proprietary data buss for the gauges - so they either piggybacked the old PCM or went full aftermarket gauges. That doesn't apply to the '00+, which should be able to use the standard 3800 PCM with the right OS for the gauge cluster data buss that I don't really know a lot about yet. Again, a lot of the info is picking the right part out of the parts bin, and being able to weld a custom subframe. It's the big little things, like a 4t40 that won't hold up to the L67, axles, gauge cluster, etc... they never figured that part out. The 4t65 info comes from the N-body, and the '00+ gauge data buss info came from a few 3400 swaps. I'm just piecing it all together from what's left of forums I guess.

 

[Lord Tin Foilhat]

 

[Mattstrike]

 

[v6buicks]

I've always wanted to drive one. I'd imagine a 3800 would scoot with all that body weight loss.

 

[Yaj Yak]

fucking awesome reply.


and fuck she's fantastic.