Originally posted by Y-James:
you'll get best performance by using the stock internals with the addition of the 4.0L header/exhaust. i would also recommend using the 4.0L injection
you can take the complete stock 4.0 EFI system (including the ignition) and put it on your 258 using the 4.0 head. You'll have to do a little wiring work, and you'll need to get a harmonic balancer and crank position sensor kit to make it all work, but at least it all bolts together.
Another option is to just put the complete 4.0 in your Jeep. You'll need the same harmonic balancer and sensor becuase your current bellhousing won't have a provision for the 4.0's crank position sensor, but otherwise it's a bolt in.
Novak will drill bellhousings to accept the CPS for now. For doing a 4.0 swap that beats the crap out of the $300+ that the harmonic balancer and sensor would cost from Hesco. It also beats what AA is charging for their "adapter" bellhousings for the 4.0 swap.
