Thanks. I have found 168 tooth flywheels as heavy as 30 lbs. I need to look at the relationship of the bell housing to the firewall and see if I can fit the 3925505 bell housing in there with a 30 lb 168 tooth flywheel, (and check front driveshaft clearance). If it all would fit, that seems like the easiest way to go. The way I've come to think about this it seems like the bigger and heavier the flywheel is, the better off I think I'd be with the little I-4. The smaller the clutch is, the faster that truck tranny should sync into a shift.
I got my Merc 120 head back yesterday, cleaned, magnifluxed and surfaced. I painted it last night. The merc valve kit should be here next week. I lucked into a Clifford intake manifold on Ebay for $125, and I have a fresh rebuilt Rochester 2G still in the box. I also have a junk merc head to use as the stand for an exhaust header. I think fabbing the header will be the biggest challenge. It seems like 120 hp and 4500 RPM should be achievable with this setup. I'm hoping that will get me 55-60 mph up and down hills so I can more or less keep up with traffic. It will probably be next winter before I take it off the road for the power upgrade.
