Modern Atlas Engine Swap, not easy but worth it

[Natron037]

I am in the process of swapping a 2004 GM Trailblazer Atlas 4.2 inline 6 into my 67 Patrol. I am using the engine with the stock ECU reflashed with the auto trans, anit-theft and other junk removed from Jeremy at Limeswap. The engine will use the factory 4L60E bellhousing with an adapter plate bolted to a jeep T18 trans and dana 20 transfer case. The ECU reflash is $150, the engine was free after parting the rest of the trailblazer out, the adapter plate, flywheel mod and pilot bearing holder are about $300 from my local machine shop and the trans/transfer case were $100. This whole package is about the same length although it is set back 3" further for the shifter to come out the hole in the floor. It's 270hp, 4 speed, and a 2:1 transfer case. I am also swapping in Jeep CJ7 widetrack axles (front is a perfect fit) with 2.73 gears. With the 6.32 first gear in the T18 it will still pull away from a stoplight fine, but 4th gear will cruise easily at 65mph (max speed for a patrol I think!) If anyone is interested in this swap, as I am still working out final details, I am glad to share all my info and contacts. I looked at many possible options, even a vg30E, but decided this was the most bang for the buck, even though it was more difficult. Please email with any questions Natron037 at Ya hoo

[mad4hws]

I am anxious to see how this transformation takes place. Please keep this thread updated.

[Esteban]

Visited Nathan yesterday since I traveled to collect the engine and axles that he sold me. Really nice guy to talk nuts and bolts. His fabrication abilities are great and his shop in the back of his house will be a dream for any of us.

I was impressed a lot with the Atlas engine (GM) that he has installed in his Patrol. The power and torque of this engine rivals any V8 (270 hp, 275 pound-feet torque). Looking at this engine in the bay of the Patrol looks clean and not cramped like the V8 examples that we've seen. At the moment only the engine is in place.

Once this project is complete, it will definitely be a reference for anybody that wants to do an engine swap.

Thanks Nathan for the help with the parts and loading them into the trailer.

[L60Boerne]

Thank you both for blazing this trail. At some point a good modern engine option will be the best next step forward.

Or it might just get a few motorless Patrols moving again sooner.

P40 Patrolling...for now,
L60Boerne

[Natron037]

I have yet to see how it all turns out. I like doing things differently than the crowd, which always means harder in the long run. This swap should make a Patrol go along at highway speeds and drop the 0-60 time by 20 seconds at least. I would have liked to stay Nissan, but they have gone back to the V6 in almost everything these days, the exception being the RB engine from a skyline. I had originally purchased an 88 pathfinder for the engine swap, but fitting the wide v6 didn't seem right to me. I have always been a fan of the GM Atlas inline 6. They are smooth, narrow, short and make great hp and tq. For instance, from the crank centerline to the top of the intake on the atlas is only slightly taller than to the top of valve cover on the Nissan engine. The atlas is about 1.5 inches shorter as well. I have heard of Ford 300/6 engine swaps, but they are looong! Truth be told, a better, and much easier swap would have been the 5cyl version of the atlas in the chevy colorados and gmc canyons. You can find them with 5 speeds transmissions and can adapt passenger side drop transfer cases. They are becoming plentiful and cheap. The added bonus is you can move them forward almost 4 inches so the rear driveshaft isn't ridiculously short. Even the 4 cyl version isn't that far off in HP from the original patrol, but you do sacrifice torque. I will keep you all posted with progress reports, over and out.

Nathan

[L60Boerne]

Nathan, Very interesting. I sure wish I could do those things. Please keep those notes.
Patrolling with parts from everyone,
L60Boerne