Does anybody know the difference between the DX and STD ECU? My '91 Wagon with the D15B2 has a 37820-PM5-A30 ECU. I have an '89 STD ECU, part number 37820-PM5-A180. The wagon drives the same with either one. I'm after better MPG and wondering if the STD ECU will make a difference. I'm usually below 2000 RPM, if that matters.

Also, does anybody have lift/duration specs of the DX and STD cams?

Thanks.

 

Hello? Is this thing on?

 

STD ECUs are PM9, NOT PM5.

You'll see no difference anyways unless you run the STD throttle restrictor plate and manifold/cat (it was like the HF's).

 

I have a sohc zc and I'm running the I/M and TB from my old d15b1. I just went and got a pm5 ecu to replace the pm9 that was in it and it made a nice difference. More power and way better response off the line!

 

When I had DPFI in my STD, I replaced the PM9 with the PM5 and it made the motor idle and drive smoother. The PM9 would stumble and idle a bit rough. Didn't notice any power increases though.

 

Civic

3DR
88-89 DX 5 speed
37820-PM5-F01

90-91 DX 5 speed
37821-PM5-A00

88-89 STD
37820-PM5-F21

90-91 STD
37820-PM9-A01
37820-PM9-M00

4DR

88-91
37820-PM5-F01
37820-PM5-A01

90-91
37820-PM5-M10

5DR
88-89 5 speed
37820-PM5-A08
37820-PM5-F01

90-91 5 speed
37820-PM5-A09

I didn't even get into CRX's or auto ECU's but just to clarify how many variations there are. I can only assume that car's that carried more weight (4DR/5DR) had perhaps more aggressive timing/fuel maps to compensate for the weight? Only a guess though.

 

Cam shafts

88-91 3DR/4DR/5DR Civic DX/LX 5 speed
14111-PM5-A10

88-91 Civic STD
14111-PM5-A00

 

Std came with pm9 only...

 

Read my post, in 88-89 it came with PM5, that's directly from Honda's website