I also have found that a racing head makes tons of difference. The fins are much better for cooling and the aluminum will not warp like the chinesium does. I have one that I used linked, it made a ton of difference on hills. I also noticed improved compression and power
https://amzn.to/3HJkIP8- 50$ Here is the link to the head that I use. I also attached some others that I didn't trust as much, but they are cheaper
https://amzn.to/3bqwxhj 43$
https://amzn.to/39JT1JE 36$ (much better fins than stock, but chinesium rather than milled aluminium)