I have a p28 ecu and rywire harness that I'am about to use for my d16z6 in my dx rex. If I decide to go b16 or b18c later on can I use my harness and just get my p28 chipped to work with a bseries?

 

yes to your whole statement

 

are the obd1 d16 and obd1 b16 distributors the same?

Iam going through a mid swap crisis. I have the d16z6 engine ready to go in w/ the following parts...
XTD stage 3 clutch and flywheel
new dizzy
new timing belt, water pump, tensioner pulley
motor mount inserts

additonal things I bought that I can reuse are
255lph pump
550cc injectors
p28 ecu
rywire harness

 

no they are not the same

 

internally, all obd1 d, b and I belive even h and f series are interchangeable internally.
the case is what sets them appart, the case is what bolts to the head, thats pretty important. even so, obd2 works in this manner as well. for example, I have an obd2 p75 internals in my p28 dizzy case.
hope that answers your Q

 

Yea the internal parts are the same, but the problem mainly comes from mounting the dizzy. Even D series dizzy's aren't interchangable.