EO2K

iTrader: (37)

I've none, but I'd love to see exactly what you did and how you got it to work.

GREY GHOST

we are doing this conversion also, will the stock 99 ecu handle the camshaft sensor moving through the vvt movement? just trying to get it to run with the VVT tuner.

EErockMiata

To get the vvt motor to run on the 99 stock ecu with vvtuner you need to do the following.



-VVTuner Pin 8-15 to OCV (Polarity no care)
-VVtuner Pin 7 to 12v hot that's hot while cranking (hook it up to room while testing to rule out using the a 12v source that's not hot while cranking)
-VVtuner 9-14 to ground
-T off the cam/crank sensors (Grey with red and Grey with blue) that are going into the DB-37 connector to the ECU and send them to the cam/crank inputs on the vvtuner. You cannot hook the system up in pass through. Go into the VVtuner via Serial and disable pass-through mode.

I think that's it. The only thing I'm not 100% sure on is the ground. I don't remember if I grounded both 9/14 but i'm reasonably sure I did.

Re posting this below image brain originally posted earlier in this thread for ecu pinout info. This diagram shows you hooking it up with the stock ECU in pass through, that does not work. However the other info in this image is helpful.

GREY GHOST

this post was what I was looking for. when we wired it up as shown it started on the first try an the VVT tuner worked.

Braden McKay

Just dropping by with this thread dig to say that this worked. Diy could or would not explain the pinout of their supplied pigtail, which indeed matches the colour coding above posted by EErockMiata.

Ignoring the pass through wiring, the pinouts for the ecu supplied by Brainiac is accurate, just remember you only want to tap into stock ecu cam and crank wires, not cut and pass through.

Definitely ground #9 and #14, ignore any/all other wires in the pigtail.

Thanks to these two posts I was able to get my vvtuner up and running for my 99 MX5 (I'm in Australia) when DIY was unwilling to help/provide the info contained in this thread.

Lastly I'll just add, don't take your vacuum signal from FPR vac hose as that goes to a solenoid which switches and confuses the vvtuner. Grab it off a vac line after the throttle body.

hector

Congratulations on getting this working. For posterity, please check back in with a dyno plot with and without the VVT working. I think that is what really is missing from this thread. I believe many of us would like to know what type of performance gain there is to be had from having a stand alone VVT controller on a stock non-programmable ecu. Especially in your case when you did not have a VVT engine to start with.

BTW, the pinout posted and reposted in this thread is from DIY. I know as I installed a VVTuner many moons ago and got that image from them at this page https://www.diyautotune.com/support/.../installation/

What more were they suppose to explain? This is a rhetorical question. I'm sure you have your reasons and I am not privy to your exchanges so I may be judging the situation all wrong. But there should be some DIY from a company that calls themselves DIY or maybe that's just me.

Braden McKay

Excellent idea, it would be handy to know what the gain from this box specifically is worth.

I specifically asked them if they had the colour match ups for their supplied pigtail harness, as was posted in this thread e.g. green wire =, green and black =, purple =, orange =, etc. If you're selling a pigtail, somewhere along the line you have this information available.


Other than this, the preferred or correct ways to integrate this on stock management as this thread says/as I have done. The reply I got was to install an NA8 CAS to run my stock ecu which was baffling to say the least given I have a 99 NB and intimated this to them. When I queried this, they said to "split the cam crank wire or use passthrough" - splitting would imply passthrough anyway???

The information on that link isn't particularly helpful to people who want to install a vvt motor in a stock management 99-00 NB whereas this thread is 👌

The only way I got this up and running was with the info in this thread, so I guess for the money I'd have expected at least this much information.