Need some advice/suggestions

[mjr45]

I've got a 75 280 with 133K on the original motor (getting a little weak) and a 77 L28 with 80K on it, but hasn't been run in probably 10 years. Question is do I swap the old motor for the newer and then rebuild the older or other way around? I don't plan on doing any major engine mods, probably just get valve job on the 77 (B4 swapping) and some minor ignition changes. Clutch definitely has be redone, but there is a decent clutch on the 77 motor. Give me some suggestions. Thanx.

[d240zx2]

I'd go with what's working. If you want to refresh your existing running engine, you'll likely have more confidence in the results. Typically, L engines run well past your current mileage before they suffer any significant decrease in power. I'd re-do the clutch and keep on drivin'.