Topic: 2.5 to GM 3100 Swap?

[RNandKT]

Has anyone ever tried a swap to a GM 60 degree engine?

So the bolt pattern on the 2.5 is the same as a GM 60 degree V6. And before I go too far I realize we are talking light duty tranny here, but I am not talking about the bigger 4.3. Bare with me a moment before flogging this one.

The stock 2.5 makes somewhere around 120-130 HP and in the higher RPMs, and pretty dismal torque around 130 ft lbs. The AX5 is not terribly tough but holds up fine in most cases to that power. Lets say for example you are running 32's or 33's and the 2.5 is just a bit over taxed and frankly worn out. Instead of a highly complicated swap, why not, pick up another AX5 (they are often given away) rebuild it, and then at the same time find a wrecked Grand Am and pull the GM 3100 (3.1) anf mate it together and stuff it in. They make about 160 HP but more importantly 185 ft lbs. They are everywhere and cheap as dirt.

Use a standard Grand Am clutch, and should bolt right up. Make sure you get the engine computer and you will of course have to deal with wiring, exhaust and motor mounts, but you should get a motor that is about the same weight and a decent increase in usable power without being an instant transmission killer, and without being a huge swap project.

Odds are you would actually increase MPG's too. Thoughts on this?

[Jeffy]

It was a somewhat common swap with the early XJ's since they used the 2.8L.  People soon found out it wasn't worth it though.  The engines weren't without problems.  Manifold gasket issues,  Head gasket issues, Piston slap issues, camshaft issues, etc...  You're also on your own with mounts and wiring.  The 2.8L guy's would keep their injection system and slap larger injectors into the TB.

Another thing to think about is where the power is on the power band.  It's all high up which isn't where you want it on a heavy vehicle.

Then you're going to have to get parts from a Grand National or F-Body to fix a lot of the issues you will run into with a transverse engine swap.

[Mnkyboy]

Typically the 2.8l guys would get a 3.4l from a Camaro and bolt that in, the AX5 seems to hold up ok but if you wanted you could swap in an AX15.

[dwtaylorpdx]

Goodwrench used to sell a repower kit for replacing the 2.8 FWD engines with the 3.4. It was really priced pretty well, and the 3.4 makes way better torque than the 2.8.

[RNandKT]

Seems like every time I come up with a new frankenstein idea, I always come back around to just simple rebuild on the 4 cyl when it gets tired and save the money to put in gears instead.

Thanks for the feedback guys. Would probably be an OK swap, but I found a core motor today for free and rebuild kit is just too cheap to want to explore the swap any further.