90-91 Distributor TD-23U / 24U difference??

ASSISTANCE Stock Engine-Bay Components
1

I searched for TD-23U & Td-24U before posting…only found a WTB thread.

Does anyone know the difference between these? I’ve rebuilt a B18A composed of 2 junkyard motors, niether of which came with a distributor. It’s getting to be time for a dist. and I ran into this snag.

What’s the difference?
I’m using a PR4-2 head (# cast above the #1 ex port) and a PR4-A10 ECU if it makes a difference.
The head is definately a 90/91 head; A 90 if you can go by the other numbers on the EX side.

Thanks for any help.
-TJ

2

The only wiring difference between 90 and 91 is the PA sensor.

3

PA sensor…What’s different? Wire color/position?

4

I did a little search for you and I think they are interchangeable.

http://www.andale.com/stores/sf_itemHome.jsp?foo=bar&sid=212250&cid=12633049&lid=100459079&mode=1&catId=1355352&parentCatId=1299368

5

Yeah, that’s where I was going to get one & where I learned about the 2 different units…
I didn’t bother reading this part until now though:
* This distributor is compatible with the following OEM housing #'s: TD-23U & TD-24U

Still curious what the difference is though.