2.4 vs 2.7 vs 3.2 rebuild costs variance?
 

Good morning - assuming same/same condition is 2.4 or 3.2 that much less to rebuild to a street engine (not race) level?

Assuming that the engine is basically in decent but tired condition is there a big cost swing between the different flavors of engine?

Thanks.

The basic costs are about the same, meaning new parts and machine work costs are near equal.
The cost variance comes in the magnesium case of the 2.4. Long term the mag case 2.7 could require lots of extra work to straighten for the build. Mag case can be a bottomless pit with line bore, case saver and new studs and machine work required
The long term residual value is in the aluminum cases
With the 3.2, make sure you get all the electrics to make it runable
Bruce

Thanks for the reply.

So, basically, if all the other costs are close to equivalent why not build a bigger engine with an aluminum case and avoid the potential magnesium case issues/work required at some point.

Is that about right?

I think your understanding is right on. It is possible to rebuild a 3.2L without machining most of the time. A 2.7 is much less stable.

Thanks

I would add that the fuel systems, both carburetors and MFI on early engines can be expensive if they need attention as well.

john

I had not thought about that John, good point.

I wanted to build a 2.8 SS out of my 2.2 (71T) using a 7R case. By the time I factored in the costs and potential leakage on the 2.7 I bought a decent used SC engine. ... job has mushroomed to a 964 based 3.8 ... another story :)

only other factor is overall package value if the 2.4 or 2.7 is original to the car (numbers matching)

The big question mark with an SC or Carrera motor is cylinder type. If you have a motor with Mahle cylinders, there is a very good chance they can be reused.

On the other hand, with KS cylinders most will say they should be nikasil plated and used with new pistons. That can be around $2K more than reusing good cylinders.