Smitty

1986 AMC Jeep Cherokee Chief
3.4 liter Chevy V-6
307,000 miles

This here is Ol' Smitty.

I didn't pick her name.

It's carved in the underside of her hood and who am I to argue...

When AMC released the XJ one of the engine options was a Chevy 2.8 liter 60 degree V6. Ol' Smitty's factory 2.8 made it to 306K and was still running when pulled. Barely.

The wheezy, bent push-rod, mechanical butt-hole 2.8 was swapped with a 3.4 liter from a 1993 Firebird.

The engine swap from the 2.8 to the 3.4 was pretty straight-forward. Get one from an old Camaro or Firebird. You can use the front cover, oil pan, oil pump and pickup along with all accessories and pullies from the 2.8. The motor mounts, intake, valve covers and bell housing bolt right up with no problems.

There are a few things to note with the 2.8 to 3.4 engine swap though...

First to note is the 3.4 has no provision for a mechanical fuel pump like the 2.8 so an electric one is needed. I went with a Carter. Make sure you run a separate relay switched power feed when you do this. The Cherokee's wiring is weak enough without adding the drag of a poorly wired fuel delivery system to the mix. I wired mine up so it came on with the ignition but added a hidden switch to the circuit. Keep it a secret, remember to shut it off when you park and you won't have to look far if someone steals your Jeep.

The second thing is the 3.4 has an internally balanced crankshaft making the flywheel from a 2.8 a bad match as it has a rectangular weight cast right into it. Take the 2.8 flywheel to a machine shop and have the weight milled off flush and then have it balanced. After my flywheel had the weight machined off it needed no additional work to get it balanced. Leads me to believe a guy with an angle grinder and some patience could get close in the garage. Get the thing re-ground while you are at it to save the new clutch and throw-out bearing you are putting in. You are putting a new clutch and bearing in right? Thought so.

The third item is that the 3.4 block has no clutch linkage boss so if your clutch is not a hydraulic setup you will need to convert it. Probably not an issue with the XJ but thought I'd mention it anyway.

Fourth and final gotcha, that I'm aware of, is the water pump on the the 3.4 is made to spin in the opposite direction of the 2.8 alternator and power steering because it was used in a serpentine setup in the f-bodies so make sure you use the 2.8 pump.

Back in the day you could get a few high-perf goodies to help the anemic little 2.8 make a bit more power. You can still get your hands on an old Edelbrock Trorker II intake if you hunt around enough. The Torker II intake setup was a two-piece deal with a base and your choice of a two or four barrel plenum that bolted on. The two-barrel plenum let you use the stock carb and and the four was set-up for a Holley.

Edelbrock Torker II intake and a Holley 390 CFM 4-barrel carb.

This intake and carb setup leaves no room for an air-cleaner under the XJ hood so I opted for a Bronco set-up that had the same diameter opening. The thing fits perfectly and looks factory.

Mid-seventies Ford Bronco V-8 air cleaner for hood clearance.

The cast Fiero valve covers just looked cool and I couldn't resist. After stripping the coating and hitting them with some scotch-brite I thought they looked right at home.

Fiero V-6 cast aluminum valve covers.

The AMC Jeep Cherokee XJ was one of the first vehicles in the world to be built by robot welders. Her kind basically revived AMC enough to be salable and in turn a saved a bankrupted Chrysler when they bought American Motors. Chrysler went on to reap the benifits of the XJs popularity and a newly designed inline 6 that gave the XJ the low end grunt sorely needed.

All of the sudden wagons were cool even if the class named station wagon itself still brought up images of the family truckster. Most of us got over that and within a few short years everyone was churching it up by calling them SUVs.

Hello tree