強化汽門彈簧通常是提高轉速的前一步,
如果你其他都沒動的話, 沒什麼差別

改汽門彈簧的目的為防止valve floating
意思是說高轉時cam推動汽門的速度太快汽門彈簧卻跟不上cam(彈簧K值太小),
些許的valve floating 沒什麼大關係, 但嚴重時會導致汽門敲到活塞你就知死啦

BTW
Valve float can be identified on a chassis dynosheet as a sudden very sharp
or steep drop in hp (in the order of 5% [7-10 whp] or more) at the last
500-600 rpm before the redline.
某大濕的判別法