Martin Y

I aim to refit my DIYPNP, salvaged from my previous '94 Roadster, to another of the same model, and would like to add a 36-2 crank trigger wheel. What extra hardware do I need? The DIYPNP has the sequential injection mod board added, so I'd like to give it a synch signal too.

Looking at a '99 parts diagram I guess I need a crank pulley and boss pulley, which the trigger wheel gets sandwiched between, but I don't think I need to change the timing belt pulley. And I'll need the '99+ crank sensor.
When it comes to the synch signal I suppose I could fit a '99 cam cover, cam sensor and cam pulley, but can I instead use my existing '94 CAS? I gather FM's Hydra has a trigger setting for a 32-2/CAS combination but I'm not sure that exists for MS. I'm sure I read something years ago, perhaps by Reverant, showing how to mod the CAS to give only one pulse per revolution. Is that the only way to use the CAS for this job and if so, does anyone have a link to the mod?

(I may have a supplementary question about switching a 6-rib supercharger pulley from a '94 to a '99 crank pulley and whether that needs a particular spacer, so if you happen to know those details by all means jump in.)

Sjevsspeed

Are the 99 cam pulleys same size and do they bolt in without modification?

Martin Y

Yes, the pulley just has a number of raised points to register on the sensor but otherwise it's the same and fits NA cars.
Used example here: https://www.autolinkmx5.com/camshaft...sed-8648-p.asp

bmxfuel007

iTrader: (21)

I converted my 94 to using 99 sensors on my ms3x because I wanted to get rid of the CAS (no more oil leaks)

I got the FM 36-2 with a NB crank sensor along with an NB crank pulley/boss, and also an NB cam gear with the two nubs along with a NB valve cover for the cam sensor. I believe if you get a 96+ crank pulley boss it should be ok as the 96 also had a timing wheel. You'll see the difference if you compare the pulley bosses to each other from a 94 to a 96+. Also if you decide to delete the CAS, you'll also need that little sealing cap to put in its place

The CAS on a 94 provides both the crank and cam sensors needed, so when I wired up the new crank and cam sensors, I spliced it into those wires and then set my spark mode to Miata 36-2 and set ignition input capture to Falling edge instead of Rising edge

Martin Y

Thanks. It looks like swapping to all-NB parts is the straightforward way to do it.