RX7Club.com - Mazda RX7 Forum - 13BREW half-bridge RX-8 build thread

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13BREW half-bridge RX-8 build thread

Hello everybody,
I am Alexander from beautiful town Vladivostok - the closest Russian town to Hiroshima.

In this thread i want tell you how to put this:
https://img-fotki.yandex.ru/get/5279...749a9719_L.jpg
IMG_20160922_184417.jpg

into this:
https://cimg8.ibsrv.net/gimg/www.rx7...fc6edd114e.jpg

I know i am not the first in the worl who put 13bREW into RX-8, but i did it my own way, and sure nobody else did it that way.

This is half-bridge ported REW, with original REW front cover, oil pan, REW oil metering pump, 6 fuel injectors, GTX35 TIAL turbo, and it is controlled by stock RENESIS ECU.

I just fit loom from renny to rew and adopt some sensors. No piggyback ECU, no standalone ecu. just openport+ME. Stock drivability fully kept.

Here is first start video:

Project was started year ago, and it is almost finished. I'll keep this thread with more info and updates day by day.
Bye!
Alexander.

Cool build. Always like turbo rx8's.

I had no idea that the stock renesis ecu could do so much. Also, never knew that Russia came so far south towards China, the Koreas, and Japan. I must have slept through geography class. Now I know!

Atkins rebuild kit with solid corner seals, OEM side seals.
+ RA Classic apex seals:

https://cimg0.ibsrv.net/gimg/www.rx7...5c5d0f925d.jpg

https://cimg1.ibsrv.net/gimg/www.rx7...c02c981efd.jpg

https://cimg2.ibsrv.net/gimg/www.rx7...66e881564d.jpg

https://cimg3.ibsrv.net/gimg/www.rx7...bc7c080f3c.jpg

https://cimg4.ibsrv.net/gimg/www.rx7...40fb531d2c.jpg

OS-giken single disc ceramic clutch

https://cimg9.ibsrv.net/gimg/www.rx7...e7851109ca.jpg

Nicon rotary REW->Renny trigger kit:

https://cimg7.ibsrv.net/gimg/www.rx7...de06acba39.jpg

This kit include mount for relocating eccentric shaft position sensor a little bit forward, and trigger disk that has similar shape as stock renesis, but holes drilled with offset, to match RX-7 sensor location.

Engine management.

So. how to control REW with REW OMP by renny ECU? I have no idea why nobody did it before, but this is very easy. Much more easy than put whole front cover with OMP from renny to REW.

The advantages of renny ECU and loom:
- Coil on the plug ignition system
- Full integration to body electronic: ESP, traction control, Gauge cluster - everything works perfect including MIL indicators. You can even pass the emissions in some countries where they use only OBD tools.

With only one possible problem - elemination of MAF sensor can be not very easy (but i can, this will be next story)

Everybody see the difference between renny and REW OMP. but difference not very big.

https://cimg9.ibsrv.net/gimg/www.rx7...16aeeab117.jpg
Top - REW '99 spec OMP. Bottom - renny

Any OMP since '89 till 2008 almost identical. It consist of stepper motor and position sensor. Controlling of stepper motor is absolutely the same over the years - it has 6 wires (2 for power, 4 for control) and even wire colors did not change never. So connecting stepper from '99 to '03 loom is easy - you just connect red wire to red. black to black, yellow to yellow, etc.

The only difference is position sensor. Rew sensor located inside OMP, and use 3 wires analog design (Like TPS) - one wire feed constant 5v, one for ground, and third wire linear output voltage according to actual OMP position. Renny sensor has switch-type design, and it is short almost everything. Except moments, when stepper turns more than 50 step.

To connect REW sensor to Renny loom simply use this:

https://cimg9.ibsrv.net/gimg/www.rx7...8b7909b746.png

https://cimg5.ibsrv.net/gimg/www.rx7...375cf3ffec.jpg

The most hard part can be - is adjusting variable resistor. there you can use Forscan or MazdaEdit tool, and look at OMP behavior at first start up after reconnecting battery:

https://cimg8.ibsrv.net/gimg/www.rx7...6a68cc623a.png

https://cimg9.ibsrv.net/gimg/www.rx7...486c129ffe.png

MAF sensor finally eliminated:

Also, i put all needed external sensors + tuning interface inside screen on the dash:

Now i am sure, that this is the only one RX-8 in the world running Speed density (MAP sensor) on stock ECU, with REW on stock REW front cover.