does the H23 intake manifold have the IAB setup like the H22 does?

 

yes it does

 

so would the P72 be the best chipable ecu to use with the h23?

 

If you are running hondata you can use the p72 I believe, I use the p74/75 on my h23a. If you are just looking to upgrade ecu's running a vtec ecu is pointless. I believe the p74.75 disables the secondaries though, at least that's how it was when running the hondata 4b. They might have fixed this on the s200 version.

https://honda-tech.com/zerothread?id=567799

 

aight, looks like i'll be using the P28 ecu with the IAB's controlled by something like a nitrous switch. thanks!