It is important to know when replacing belts on an early Ford that the correct belts have a different pitch and cross section than ordinary off the rack vee belts. The right belts ride up in the pulley groove, and when correctly tensioned they don't reach the bottom of the groove. Ordinary belts usually must be overtightened to prevent slippage which, in turn places strain on water pump and generator bushings. The belt for your '34 is 40-8620. We buy ours from C&G. There is a reason they are more expensive than common vee belts.