Ray,
If you'd like an engine that revs up quicker (and less rotational mass), consider using the flywheel from a B21 or B23. They're about 10 lbs lighter than the B230 flywheels. The heavier flywheels give a smoother idle, but the lighter flywheels rev quicker.

For more info on this subject, check out Paul Grimshaws book on Volvo Performance. -and you can get some of the flywheel info online at his website:
http://www3.bc.sympatico.ca/Volvo_Books/maint9.html

Quote from Paul Grimshaw: "The old racers adage of one pound of reduced rotational mass equating to 100 lbs of vehicle weight holds true!"

God bless, drive safe, and listen to Don Foster.
Fitz Fitzgerald.
--
'87 Blue 245, NA 237K

The flywheel will fit.

I once swapped a flexplate (and ring gear) from an 8-bolt B20F 142 into an '87 740 with a B230FT. Fit like a glove and worked great, 'til the moron wrapped the car around a pole...

The K-jet injection from the B21 would be tougher to swap to the B230 than it would be to swap the LH-jet stuff into the older car...

Park the two cars side-by-side so you can pick from one and install in the other.

Keep in mind that you must also swap over the fuel pump (different pressures...).


--
Don Foster (near Cape Cod, MA)

Haven't done that one, but I would expect the swap to work. Transfer also the ECU, main wiring harness, ICM, a/c compressor and p/s pump. The alternator, too. That way all the belts will line up.

The electronics will be the complex part. Having the wiring diagrams Volvo Service manuals for both cars would be helpful. The 1986 still had the crumbliong insulation problem, too. Good time to replace with a good harness.

What year is the 242GT? Does it have a 16-fuse fuse panel? The 1983s had 16, but the older models had 12, and I don't know what year was the change.

Good Luck,

Bob

:>)