Originally Posted by
SkyDog75
So long as you've still got ample ground-to-bottom bracket clearance, you should be OK. Assuming similar tire width, your bottom bracket will be 31.5 mm or about 1¼ inches lower, which is a pretty significant difference. If that's too much of a difference, you could make up some of that difference by using fatter tires like HillRider pointed out.
You could also consider fitting shorter cranks to gain some pedal clearance if needed, depending of course on what you have now.