The new MacBook Air uses a Y series processor, likely for product differentiation between the Air and Pro 13″
The new MacBook Air is using a Y series processor, it’s not as low powered as the MacBook.. but it’s certainly not on par with the 13″ MacBook Pro.
Apple doesn’t list the CPU sku, only the clockspeed/core count, so how do I know this?
The integrated GPU is the HD 617 – this is a Y series integrated part – it’s quite a bit weaker than the standard HD620 and MUCH weaker than the Iris HD 640 on the MacBook Pro 13″.
The MacBook Y series part would be the HD 615.
Recently leaks of an i7-8510Y with the HD 617 appeared and this is just an i5 variant.