The Ẽfini 7

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speedjunkie
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Re: The Ẽfini 7

Postby speedjunkie » Sat Jun 08, 2019 9:14

The main reason guys don't mount them in the stock location is due to the heat, but I made a heat shield for the top of the engine and I'm planning on ducting up to the hood vent so it sucks out hot air. I like the stock location because it keeps the wires nice and short, and they're out of the way for other things you want to mount in the other locations.

I would bet that's what's happening. There is decent money to be made in that considering how many people swap LS engines into so many vehicles.

I think mine was charged with R12 originally, assuming my original compressor is one of the 4 R12 models I have haha. And of course there were two different systems Mazda put in the FDs, one installed in Japan (Denso) and one they installed once the cars were stateside (MANA, Mazda North America I guess). And some people claim that it's dependent on year or trim level but that doesn't seem to be the case. It seems to be completely random which cars got which system. I'm using an industrial R-134A now from Enviro-Safe. It's not too bad. I had thought about using ES-12 from cans of keyboard cleaner but I read it's flammable lol.

I like the switches for logging and sequential/non-seq. That's badass!

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Dwduc
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Re: The Ẽfini 7

Postby Dwduc » Sun Jun 09, 2019 9:14

That is a good idea, do you have a good source for mica sheets? It's just a pain to get to for mock up and bracket design when you daily the car.

Tonight I got the VSS at the ECU sorted out. I had it pinned to a 12v input, it turns out the VSS is a 5v signal. So many rookie mistakes! But it's coming along well.

Configured the ECU to use the factory knock sensor but it leaves much to be desired and its a single channel so the windowing is kinda sketchy but its some protection to get a little more aggressive with the tune.

I have the button and switch installed and working but I'm still trying to get the sequential system to boost and transition smoothly. I might have to mount some GoPro cameras near the actuators to be able to see what is actually happening.
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speedjunkie
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Re: The Ẽfini 7

Postby speedjunkie » Mon Jun 10, 2019 9:14

I'll have to see where I ordered my mica from, but I think I still have a good bit left if you want to use some. I'll have to look and make sure. I didn't use it for the heat shield on top of the engine though, only for the one between the LIM and turbo and I'm not using that shield anymore. For the one on top, I just used aluminum sheets and then put the sticky reflective sheet from the auto parts store on the bottom side facing the engine.

Chris installed Bosch knock sensors for me, similar to the RX-8's. I was reading up on them and if I remember right, you need to know the right frequency of the engine in order to set up the window, but supposedly they work well. However, Peter at Rice Racing was telling me they don't work for shit and to go back to the stock knock sensors, which I'd rather not do. So I'm lost now. I always heard the stock sensors were way too sensitive but I'm getting mixed info now. I don't want them because they have a lifespan and if the goo in the back falls out, you need new ones and they're expensive as shit.

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Dwduc
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Re: The Ẽfini 7

Postby Dwduc » Tue Jun 11, 2019 9:14

The frequency of the 13b is well documented at around 3.5khz. It is easy enough to find, just hook the knock sensor to a scope and give the engine a whack with something. I'm reading the engine resonance well with the stock sensor, I just have to scale the threshold of volume to what is actually knock and what is just normal combustion noise. I have found a gain setting of about .5 gives me a raw knock value of around 50 when operating normally so I set my threshold about 20% over that. The windowing is sketchy because I only have a single sensor mounted on the rear rotor housing so it will obviously be much more sensitive to knock coming from that rotor. Once I have two sensors installed I will be more confident of the protection.

I really don't like the gel filled OEM sensor. And almost all modern ECU have knock filtering and conditioning circuits allowing you to get great results from a flat response knock sensor. I think people are just superstitious about the old style resonant sensors. If you buy a quality Bosch Wideband knock sensor you will likely get better filtering and less noise than the OEM resonant sensor. All of the Bosch 2 wire sensors are wideband (1-20khz I believe) And are of way better quality.

I need to spend some time on my fuel map, I ran my first tank thru and only got 16.5mpg! Alot of it was idling and I had a ground issue that was causing the injectors to intermittently ground and dump fuel but I'm still hoping to get close to 21mpg like I did with the stock computer.

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Dwduc
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Re: The Ẽfini 7

Postby Dwduc » Sat Jun 15, 2019 9:14

Frustrated with the lack of support for integrating the OMP control I decided to build my own so I can have OMP control, feedback, and safety. Got it started last night by getting my brother to help me write some basic control code for an Arduino to drive the stepper and compare with the pot. Then I assembled a prototype today with one of my spare UNOs. I plan on using a NANO for the final product so it will all fit in a nice small package, probably a large shrink wrap sleeve. I have it basically working and stepping the motor, spent most of the day trying different combinations of input sequences to see which way each input would step it (6 wire unipolar stepper). And I got to where I'm stuck with the code again so I have to wait for my brother to come rescue me and fix the errors.

What it is: An Arduino microcontroller driving 4 N-channel MOSFETs that are powered from the 12v source, and 5v power from the Arduino to the postion indicating pot going back to an analog input on the controller. LEDs are just there to help me see the step sequence and direction.

Still to do is to read and print the digital PW load signal from the ECU and see what the ranges are so I can scale the driver to the engine load, and set up a return function signal to let the ECU know that it is operating and the current position. I plan to set up a safety that won't allow me to boost or rev over 4k during a failure situation.

Planning on feeding it from a 2 stroke tank with the RA (Sohn) adapter that will have a low level sensor that will also trigger the safety function.
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Re: The Ẽfini 7

Postby Dwduc » Sun Jun 16, 2019 9:14

Little bit of progress today.
The OMP is now stepping to the setpoints I give it, and I have mapped out a load signal from my ECU to a controller. However I can't get my PWM reading code to play along nice with my OMP control code making me use two controllers. One to read the ECU and the other to step the OMP, so again I'm waiting for my brother to come make me feel stupid. Also he can help me simplify the step code to get faster response, currently the OMP takes about 5 full seconds to get from its lowest setpoint to its highest and I wanna get that to about 2 seconds. I wonder how fast the stock system moves it? Maybe I'm overthinking it. I am microstepping the pump and I could easily cut the time in less than half by going to full steps.

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Re: The Ẽfini 7

Postby Dwduc » Mon Jun 17, 2019 9:14

It F*cking works!!
My brother spent some time tweaking and altering the cobbled together code and merged it onto a single controller. He got it working so smooth and fast that we had to add delays into the code to allow the motor to catch up!! Now I'm just waiting for the NANO to get here so I can come up with a way to enclose it with the FETs.
Also I will do a detailed writup with a parts list in case anybody ever cares to build one of these things.

So happy to see it work and follow the ECU signal smoothly, can't wait to stop premixing!

Aslo while I have my spare OMP apart I was looking at how to get more out of it for when I build for more power. The actual pump has nearly 3/4" of useable stroke but the way they have the little cam taper it only uses about 1/8" of the stroke.
Once I get my machine set up I want to try to make a high volume OMP for higher power levels.

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speedjunkie
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Re: The Ẽfini 7

Postby speedjunkie » Tue Jun 18, 2019 9:14

Holy shit, that's crazy! Very impressive. I was always afraid of premixing because I thought I'd forget, but it's not that bad. Why do you want to do OMP again? I wouldn't mind having the OMP, but I like not having the extra tank in the engine bay too and having a little simpler setup.

Maybe you can build a GPS tracker now. LOL I've been looking for one for years and can't find one that I don't have to pay a monthly fee (I'm a cheap ass lol). I read something before about guys using an Arduino for that, so you reminded me of that with your project.

Are you planning on eventually swapping to Bosch knock sensors or stick with stock? I'm really hoping I don't need to actually change, but unfortunately I can't read the logs to see for myself if they're actually working well.

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Dwduc
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Re: The Ẽfini 7

Postby Dwduc » Tue Jun 18, 2019 9:14

speedjunkie wrote:Holy shit, that's crazy! Very impressive. I was always afraid of premixing because I thought I'd forget, but it's not that bad. Why do you want to do OMP again? I wouldn't mind having the OMP, but I like not having the extra tank in the engine bay too and having a little simpler setup.


Mostly I just don't like carrying the oil bottles in the car, They always seem to leak and make a mess. I had a little custom box I made to carry multiple 4oz glass bottles that I was getting from a lab, but after several uses the seals would swell and start to leak around the cap. But mostly it just seems messy, I can remember to fill the little tank at home and not have to deal with carrying the sauce around with me.

speedjunkie wrote: Maybe you can build a GPS tracker now. LOL I've been looking for one for years and can't find one that I don't have to pay a monthly fee (I'm a cheap ass lol). I read something before about guys using an Arduino for that, so you reminded me of that with your project.


I believe I know how to make such a device, I think I can make it operate for free if you just want a location that updates like every minute or so. If it did go over on data it would be like $0.60 per month. But we could always add time between updates until it didn't go over.

speedjunkie wrote:Are you planning on eventually swapping to Bosch knock sensors or stick with stock? I'm really hoping I don't need to actually change, but unfortunately I can't read the logs to see for myself if they're actually working well.


I already got some Bosch wide band sensors, I am just waiting on the connectors and I have to get some shielded twisted pair wiring for them. I am hoping to do all my wiring at once so I will build the final OMP drive circuitry and install that along with my knock sensors, My Seq/non-Seq switch, oil pressure, fuel pressure, and traction control.

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speedjunkie
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Re: The Ẽfini 7

Postby speedjunkie » Tue Jun 18, 2019 9:14

Oh gotcha. I carry bottles in the car with me even when I had the external tank, so it's no change for me haha. I keep the full bottles in the car and I use the little funnel piece that screws right onto the top of the bottle and I just ballpark it. I used to try to use a funnel and measuring cup, but I realized it really doesn't matter if it's exact lol.

That would be awesome, thanks! I'll need to talk to you quite a bit more about this, I have so many questions lol.

Oh ok cool. I wonder if you got the same ones I'm using. I don't know for sure if Chris used shielding on my harness though. Hmmmm
That will be awesome having everything wired into one harness. Are you going to use the stock ABS sensors for traction control? Do you have ABS?


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