3 wood vs driver

[zigwah]

I've only ever measured my club head speed using a 5 iron, is there much diff to the driver?

My 5 iron was 88mph or was it 78, bugger i can't remember now lol

The reason i ask is that i recently changed all my clubs back to reg shafts and i had started to get a lot of stap hooks with the driver, was wondering if this was the shaft because i never hit it left, or something else.