SNIP The 290 will swap out with the 343 so long as you keep the 290 balancer and flywheel. SNIP ? AMC V8 engines are externally balanced using the harmonic balancer (damper) and the Flywheel. The 290 harmonic balancer will stay with the 290 engine The 290 Flywheel will stay with the 290 engine. The 343 will have it's own harmonic balancer. The 343 will have it's own fly wheel. Clutch parts are probably identical as they have no bearing on the balance of the engine. As long as you keep the right parts on the right engines you can switch them around all you want with no problems. John. _______________________________________________ AMC-List mailing list AMC-List@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list or go to http://www.amc-list.com