If you want 300whp, KA dude. You would have to put way too much money into a CA to make that power. And on the plus side you will make alot more torque.
That aside, you don’t need 300whp to drift. The CA will serve you fine for quite some time. You can easily make 220whp with a simple rebuild of the CA…add a T28 and turn up the boost.
But since you tell me you already have a running KA with good compression. I would boost that and if it goes rebuild it or get another for few hundered bucks.
350-400 hp is quite the goal to attain
Id say your best bet out of the two would be the KA with reinforced internals.
You ever think about a sr?
With hp like that you might lose reliablity for the engine to be a daily driver unless you properly build it up without cutting any corners.
In my opinion i would go either the Ka-t (easy to find parts, lots of torque)
Or get an sr20det and mabee put a gt28 or t3/t4 hybrid. You can get a redtop for a good price, and ive seen t3/t4’s in good cond go for $500+.
Whatever you decide to do goodluck , and keep us updated.