Whats better early su's or flattop carbs?

 

By far the best of the two would be the round tops!! The flat tops had problems with internal warpping causing a rich mix and vapor lock which causes driveability problems. Hope this helps. MC

 

SU's where really advanced for there time !!! and still are quite a good carby imo,

Though id much prefer Webbers

 

Early SU's are considered a perfomance upgrade. my 260z has the 240z carbs and i love em. set em, forget em and the sound when you open it up is fantastic.

My only issue with them is that you really should get either new air filters or ensure you get a 240z airbox because it's not a perfect fit and you'll get some leakage with the old SU's and 75 or later airbox.

you would certainly lose all the emissions crap that showed up on the later models and sapped power.