So I thought I would share my experiences with honda tech.
I have painted wheels in the past with the same process.
1. Cleaned part with soap and water, then de-greaser.
2.Used a brass wire brush and sand paper.
3. I used toilet cleaner with hydrochloric acid. More scrubbing and many coats of toilet bowl cleaner. (this attacks the aluminum and removes the oxidation)
4. De-greaser again
5. Paint



I just had some left over red VHT caliper paint.
It says to bake it, we will see how it looks after that.

 

Looks good! This seems like a piece that would have benefited from a light media blasting but it seems like the HCL worked for you. Now only time will tell for durability.

 

Thank you for the detailed tips, uberEFtuner.

The paint job looks pretty good so I think I'll have to try your method. I've had some problems with aluminum in the past...

 

can a wastegate withstand 400°f for an hour? Powdercoat is hands down the longest lasting or even anodize one! Turned out good bro let us all know how it holds up!