No, the 2.8 comes with TBI (throttle body injection) already. Looks like a 2 barrel carb (two injectors in a 'pod') as opposed to an MPFI (multi port fuel injection) setup like the 3.2/3.5 and I think 2.3/2.6 4 cyl engines with an injector for each cylinder. On those setups, the throttle body only flows air, rather than the air/fuel mix as a TBI does.

The swap to the 4.3 injector body (you still use the 2.8 injectors) is supposed to flow more volume through the engine and improve the HP and torque. The 'new' intake manifold is because the stock one has bores sized to match the stock TB (duh...), so to increase the flow, the bores need to be enlarged to match the bores of the larger TB.

By buying another manifold, it just reduces my downtime for the swap. I can have it bored out while still driving the Trooper, then, when I'm ready, take off the old one and swap the modified intake manifold/4.3 TB onto the engine, hopefully over a weekend and be able to drive to work on Monday.

Basically, like swapping the stock manifold and carb on a 60's small block V8 for an Edelbrock manifold and Holley 4 bbl!

Chris made a nice write up of his version of this swap, I'll go find it and post the link...

[edit]http://www.4x4wire.com/forums/showflat.php?Cat=&Number=415804&page=0&view=collapsed&sb=5&o=14&fpart=1#Post415876

And Chris showed up with a pic in the meantime![/edit]

I'll get some pictures of the parts and add them, that should help too.

Jay