Hondata

Since the si reflash alows the motor to rev to 7700 not 6800 is it a good idea to up the oil to 5w30 not the factory 5w20?

When i dyno'ed, my reflash made me run lean up top also!

Do you have a cat? If you test with a cat in the system, the reading may be leaner than it is. You might want to see what the dyno wideband says you are at a/f wise when you are at idle. If it's not around around 14.5:1 then that's a good indication that the cat is altering your reading.

No cat ...

I have a Si reflash and from 4200-5200 rpm the A/F is fine at 13.2:1. But then from 5200-6500rpm it is at 13.9-14:1. From 6800rpm on it is back to 13.3:1. I dyno'ed on a Dyno Dynamics Dyno, it was cold in the garage at 50 degrees. Also i am at 5330ft.

You car is going into limp mode. There are a ton of things that would make it do this.

Are there any differences between the OEM rsx (k20a3) and the si (k20a3) ECU?s? Other then the manifold sensor. Are the fuel and ignition maps the same?

What I want to know is what parts do you need from the original car to do a swap (this is in reference to the immobilizer system).
I have everything but the original key I have the ECU, and the Key tumblers. I went to both Honda and an Acura Dealership. They said to rescan it I needed Acura tumbler ...

Hondata wrote:Use the Civic Si reflash for the PRB intake manifold.

What is the PRB manifold?

Hondata wrote:The K20A3 RSX does not make the same top end power as the K20A3 Civic Si engine due to the intake manifold differences.

So if we have a type-s or si intake manifold on would you recommend to go with a si reflash on a base then?

Why is the Si reflash have a rev limit at 7700RPM and the base RSX at 7300RPM when they are the same motor?