new needles needed when rejetting?

[mk2dubbin]

i am running a set of stock carbs with 280 mains and 25 pilots and it runs really well with great throttle response etc. i got a second set of carbs recently that are like brand new and am planning on putting idle screws in them and matching the jetting to my current carbs for the time being and then saving the old carbs for winter or spares. i have changed jets before and changed needle settings and all that, but was wondering if i should put new needles in when i put the larger jets in or if my needles are fine. some kits i have seen come with needles and some without. plus, i can always just go buy the individual jets i need since i already know which ones to buy...

 

another side question i was pondering a while back is about the float height. i was messing with my pilot jets a while back and checked the float height and both were set identically, but slightly under the minimum range in the factory repair manual. what is the difference between the minimum float height and the maximum float height? i assume all that this changes is a slight difference in bowl fuel volume before closing the float needle? therefore by being at the minimum it would have slightly more fuel than at maximum float distance?

 

thanks for the input!

[Larry's Shee]

Some set-ups may require different needles. If all you're doing is swapping carbs just match set-up. Personally I would just swap jets and needles, why buy identical parts?

 

As to float height I would run the highest fuel level.