spoonek4

I just swapped a rebuilt B18CR long block for my friend who got a 93 civic Si(Cdn). He used to have a B17A+94' GSR head setup. Now the rebuilt motor got:
-P73-00 pistons with stock head gasket
-ITR intake manifold
-ITR head
-new OE IACV
-GSR throttle body(could be a 17A's I'm not TOO sure coz it was from the GSR head)
-GSR injectors
-chipped P28 ECU for his old B17+ 94' GSR head setup

Engine starts up fine but it shows 2300rpm on the tachometer during warm up and drop back down to about 1300rpm after it's warmed up. It sounds like it's around 1000rpm though. And if i tap the throttle it revs up but drop back down to around 600rpm then rise up to 1300 again.

Is that pure ECU problem or is it a must to upgrade the GSR TB, injectors etc to TypeR ones also, because GSR&TypeR's are simply not inter-changable?

What kind of ECU setup he should be using?

Thanks in advance

VTECVillain

It's possible for it to be the P28, I've seen chipped P28 progz that would cause idle surge. That's possible but also make sure to check all over for vacuum leaks. Check all of the hoses and gaskets for the intake manifold.

spoonek4

Thanks a lot I will check on that.

How about the injectors, throttle body etc? Are they inter-changable at all?