Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   VVT Controller (https://www.miataturbo.net/megasquirt-18/vvt-controller-53228/)

NiklasFalk 11-07-2010 05:59 AM


Originally Posted by engled (Post 653357)
The current controller will output to anything expecting to see a NA CAS or the NB crank/cam sensors. Whether it's a MS, factory computer what ever you want to send the signal to. You can not bridge the signals, you have to go through the VVT controller.

Originally Posted by Joe Perez (Post 653497)
Ok, looks like I was wrong.

Why is this, may I ask? On the Megasquirt, at least, I'd expect it to be insensitive to changes in the phase relationship between CMP and CKP, so long as CMP always stayed within a certain boundary between a given set of CKPs regardless of cam advance.

Or is that the problem? I've not studied the relationship between the CMP signals and the min/max advance settings of the cam. Do they actually cross over a CKP pulse depending on advance?


Does this means that I can feed the NB signals trough the VVTcontroller and then to the DIYPNP (I only read NA CAS signals in the beginning, not the NB)?

Wonder if that would fit the DB15, but thats just simple wires (and adding an extra connector is not that hard) :)

Ben 11-08-2010 03:11 PM

Here is the pin out for the pigtail harness:

http://www.diyautotune.com/catalog/i...%20shields.png

The OCV has no correct polarity, so we specified the same color for both OCV wires. The system, CKP, and CMP grounds are on the same plane, so those wires are all the same color. Same for the CKP and CMP power. The open pins, 10 and 11, can be used as extra grounds or to connect the drain wire of shielded wire. Our short pigtail harness does not use shielded wiring. We will be offering a longer harness in the near future that does use shielded wiring for the CKP and CMP connections. We're waiting on the shielded cable from our wire supplier.

Ben 11-08-2010 03:14 PM


Originally Posted by NiklasFalk (Post 653840)
Does this means that I can feed the NB signals trough the VVTcontroller and then to the DIYPNP (I only read NA CAS signals in the beginning, not the NB)?

Wonder if that would fit the DB15, but thats just simple wires (and adding an extra connector is not that hard) :)

Yes you will feed crank and cam signals through the VVTuner and then to the DIYPNP. You can have the VVTuner output NA or NB signals to the DIYPNP--it makes no difference as far as the DIYPNP is concerned, just make sure you set up the tach input accordingly in TunerStudio.

Reverant 11-08-2010 03:23 PM

On a 01-05 car, the +12V and GND for the sensors would be left disconnected, right?

Ben 11-08-2010 03:29 PM

Correct. If you had a factory VVT car you would not need to hook up the sensor power and ground wires to the VVTuner. The power and ground pins on the VVTuner are there as a convenience for those who have retrofitted the VVT head to their originally non-VVT car.

FatKao 11-08-2010 03:43 PM

Does this go for the OCV +12v as well? I'm not using the IAC wires on my harness and it would be nice and clean for me to use those wires for the OCV. One of them is wired to +12V the other goes to an ECU pin.

Ben 11-08-2010 04:03 PM

I don't see why it wouldn't work. OCV ground is pulsed on pin 8.

shuiend 11-08-2010 04:32 PM

If you use the stock wires for the Cam and Crank sensors to run to the VVT controller and they are not shielded do you think it will be a problem? I will be installing mine tomorrow and hopefully it all works.

Ben 11-08-2010 06:06 PM

Technically shielded wiring is better, but I doubt there will be any problem using standard unshielded wiring. Mazda didn't use shielded wiring, assumably to cut costs. So we're offering the option of a harness with either shielded or unshielded wiring, or at least we soon will be. So those who want a technically superior solution at a higher cost have a suitable option, and those who prefer a solution that should work fine at a lower cost but is technically not as robust also have a suitable option.

shuiend 11-10-2010 10:36 AM

Ben, I noticed looking at the basemap that it only goes up to 105 KPA. Will I be fine running that for now even if I get into some boost? I would guess it just uses the same values for 150kpa as 105kpa correct?

Reverant 11-11-2010 05:00 AM

I received mine, will be playing within the weekend.

Reverant 11-14-2010 07:50 PM

Anyone having luck with their unit so far? I'm having partial success on the bench so far, but only partial and that's after a lot of tweaking.

engled 11-14-2010 08:03 PM

Mine has been working for some time now, what kind of problems are you having?

shuiend 11-14-2010 08:17 PM

Mine is installed and connected and seems to power on and I can change settings. Hopefully I will get my car started and actually get to test it out this week. What types of problems are you having?

Also is anyone else's LED not working?

Landrew 03-23-2011 11:01 AM

Any more reports on how well it works on the car driving ?

Reverant 03-23-2011 11:05 AM

Mine is working nicely, top end is the same but now there is a lot more torque down low.

shuiend 03-23-2011 11:20 AM

I installed mine on my friends 99 with a VVT motor and his response with the stock map it has increased the midrange power a ton.

Landrew 03-23-2011 11:32 AM

I should really get it, to bad it's proprietary and we can't build one up for a quarter of that.

Ben 03-23-2011 12:04 PM

I'm not sure how to take that.

If you meant that you wished that the VVTuner was sold in kit form at a discount compared to the current assembled model, we're working on it.

The reason why the current model is offered assembled only is because a couple components went EOL (end of life) after the board was designed. Kevin worked out a solution using different components, but they were not direct swap. We thought it would be difficult to explain to people how to implement the new components, so we elected to build out the entire batch and only offer as assembled units.

Kevin has worked out a new board that's easier to assemble, which will be available at some point in the future (I'm not aware of the timeline, however I believe it will be a couple months). Meanwhile, assembled VVTuner is in stock.

So far, we've heard nothing but good from our customers after they've installed the VVTuner. :)

Landrew 03-23-2011 12:06 PM

Sorry how that came out - yes I just got my first MS a week ago and it would have been pretty cool to have VVT built in. Nonetheless Reverant was very nice in building up the VVT DB-15 cable so I could PNP your controller into my board just like that.

The DIY VVT kit that is coming - what kind of savings over the fully assembled are we looking it ? As in how long do I want to wait knowing I could have more power but save a few bucks. I'lll probably just get the assembled one right away.



I took this quote from Y8S when he was doing VVT research:
The green line follows the blue line up to 3000 rpm and then drops down to the red line. At low RPM in boost, I lost power by retarding the cam. Significant power: 28 whp / 41 ft-lbs at 3500 rpm! I think you'd all agree that 33 ft-lbs from 3200-3800 is a lot of area under the curve.

Wow, is that how much i'm losing by recently giving up my VVT control!! I need to get that back. 20 some hp for $200 is a deal and a half - Sounds like K&N filter propoganda but this time it's real.


All times are GMT -4. The time now is 10:12 PM.


© 2024 MH Sub I, LLC dba Internet Brands