High Rev Missing

[Dennis McAllister <svrx@c2i2.com>]

I recently bought a 1979 Spitfire that had been mostly restored and I believe 
the Carbs 
have been rebuilt engine redone and a new tune-up. It runs great but at 
4500-5000 rpm 
there is a very noticable miss and jump. If I back off the throttle, it goes 
away...but 
here in AZ the freeway speed limit is now 75 and my little spitfire doesn't 
like to get 
up there in any hurry after about 65! Any advice?