stevos555

I was just talking to a person familiar with MS product line and was told that 96-97 miata wiring harnesses are prone to ground issues and that I should stay away from PNP boxes and instead run my own harness to Ms3 pro.
Is this common knowledge that only 96-97 have this problem. I see all model years got an update to MS3PNP except 96/97. Why is it so? Is this related to the issues to these MY harness problems. Before I go down the deep end and start building a dedicated harness, wanted to see what others with same year chassis did. Thanks

wackbards

iTrader: (2)

Probably don't have ms3 pnp just because demand for the product is low. 96-97 are basically functionally the same as 94-95, but have OBDII which drives more stringent smog requirements in a bunch of states. As such, they aren't as popular for heavy modification. Dunno anything about harness issues unique to those years though.

shuiend

iTrader: (24)

96/97 pros are coming. DIY is working on the test bench for them. There are no wiring harness issues so stop thinking about them.

stevos555

Shuiend thanks so much. I was getting nervous that I needed to rethink my build. I am however still very confused what to do with CMP and CKP for my 99 motor going into 97. I have been pouring over 10 year old threads by Joe and Brain and others on how to run 36-1 without CAM or with a modified CAS. Want to make sure I get the best timing stability without jitter. Considering sourcing 99 valve cover, can sensor and crank sensor with protege 36-1 wheel. Still reading for the turnkey solution but not sure I'll find it.

wackbards

iTrader: (2)

It seems like you're way overthinking this.

Simple but bad: keep NA8 VC, & only run a cas. Leave the factory na8 crank wheel in place basically as a spacer (it was only there for misfire error codes IIRC).

Better and affordable: splice your CAS wiring. Buy a NB1 VC for like $75 on eBay. Buy a new 4 tooth crank trigger wheel for $12 new. Buy cam and crank sensors.

More better & expensive: do same as above, but buy a trigger wheel with more teeth, and buy upgraded sensors from Ballenger.

Profit.

stevos555

Thank you. I know know what I need to do.
Why Ballenger new sensors for CAM and crank ? Did you mean new connectors /pigtails for 97 harness?

wackbards

iTrader: (2)

No. New sensors. Especially the cam sensor has historically been an unreliable design. Ballenger just released some improved sensors

DNMakinson

iTrader: (3)

1) Talk to the folks from whom you are goong to purchase your MS. They will guide you.
2) Pretty sure 36-1 is not proven with MS.
3) Be more plain and open about what you are doing. Right now, multiple threads, confusing timeframes, MS wheels, 97 engine, 99 engine. All a jumbled mess of info with an occasional obtuse question.

stevos555

Appreciate candid feedback.

Here is the info and my thought process /plain and concise as my cloudy brain can think of:

1. 1997 car blew motor August 2017
2. Bought a used SM motor built by SM engine builder
3. Had the SM motor rebuilt with .40 over wiseco pistons, new bearings studs, main cap hardware, line bore, oil baffle for pan, oil pump,cleaned and balanced NB injectors, port matched, squaretop TB opening beveled, 97 valve springs, head work. Reused 97 valve cover with CAS and 97 Crank Angle wheel and sensor
4. Ebay Squaretop, new RB header Radium fuel rail purchased, Fuellab Mini fpr, new wallbro 190hp, Qmax reroute purchased, front water neck eliminated, skunk TB purchased and installed.
5. Received 2 year emissions test waiver, pulled O2, don't plan on running EGR /canister etc
6. Was working with MS dealer and waited for MS3 pnp pro soon to be available

7. Was reading the treads about timing /jitter from using CAS and started to formulate a plan that a higher resolution timing would be best for a track car given timing drift on upshifts and downshifts which can be as much as 10 degrees.
8 Spoke to a tuner and was asked to reconsider the whole PNP idea and instead given the race car nature, suggestion was to go to MS3 Pro and do a separate wiring from sensors to ECU bypassing harness wiring as it's prone to issues - chasing floating or bad ground specifically in this model year miata.
9. Armed with this information, started pulling old threads that basically confirm that running a higher resolution trigger and switching to 99 sensors would be better but only if CAM can be retained by modifying the CAS teeth or switching to front intake cam CAM /99 valve cover.

At this point, I see 2 options for running the MS CKP and CMP / Sensor and 36-2 or -1 wheel from Pretege and either modifying the CAS or moving to a front CAM. Please correct me or guide me if other options exist or my understanding is wrong. Thanks