If I used a P28 ECU(obdI) for a hondata 2b setup for my 00 GSR which is obdII. You know how the obdII equipped GSR's has a secondary butterfly on the intake manifold, would I have to change the intake maniflold to a manifold that only has one butterfly or could I still use my stock intake manifold?

 

You can use your stock one, but you will probably want to make your secondary runners stay open all the time. There is a way to do this, but I don't know how personally.

 

OBDI GSR's also have dual runners and a secondary butterfly just like OBDII GSR's do. Your stock manifold will work just fine.

 

Just that if I used a P28 for hondata, I'm not sure if it controls the dual intake butterfly

 

if you are going to keep the GSR manifold you want a OBD1 GSR ecu...p72. If you are going to go with something like a Skunk2 manifold you can use a p28, which does not control the Secondaries

 

Man so pretty much going hondata with a 96-01 GSR is gonna cost about the same weather you get a P28 or a P72 I wanted to go the P28 route to save some money but now I guess imma just look for a P72 then.

 

You can use the P28 no problem. hondata will map it for the B18 specs. As for the intake secondaries, just use an RPM switch to activate the solenoid. Easy as pie. Hell, i think that the Hondata can even supply an RPM dependant output so you won't even need a seperate system but you will have to ask them that question.

If you simply want to open the secondaries all the time remove the vacuum line from the actuator. This isn't recommended though as you will loose low end torque.

Mike