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Exactly.

Lots of room behind the crank pulley for rotational sensors (CAS). The one below is the sensor from the RX8 to keep the tach, IAC, cruise, and traction control working.

Are you still using the stock PCM from the 13B-MSP? Last I knew my 04 had cruise/iac/DSC-TC integrated in the main PCM, but I'll be honest and say I haven't looked at the wiring diagrams in-depth yet.

_________________
Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.

The RX8 ECU drives the canbus cluster (tach, gauges, lights), the fuel pump, the radiator fans, and the climate control (AC relay). I'm using the RX8's drive-by-wire throttle body. To keep the RX8 ECU out of limp mode, the oil metering pump has to be connected and tucked away, and the ECU needs to see a CAS signal. That's all. The DBW throttle also controls the engine's idle. Cruise and traction control should work as well. To test the theory, I created the waveform of the RX8 CAS in an audio editing program then connected my laptop's headphone output to the RX8 CAS input. And had a little fun sequencing a song... https://www.youtube.com/watch?v=R1xj_gbQA58

The Isuzu ECU uses the Isuzu crank and cam sensors. It controls fuel, ignition, and emission control systems (OBDII). The OBDII signal from this ECU is wired to the 8's OBDII port.

An AEM FIC piggy-back ECU will be wired into the Isuzu ECU to manage the larger injectors and lock the O2s when under boost conditions.

Ah, informative!

I know of the OMP issue, but I assumed that the stock PCM would also throw a CEL if the fuel trims were outside expected/secondary air injecttion/etc was disabled. But a copy of MazdaEdit would likely turn those off.
Are you copying the stock Eccentric reluctor plate pattern to the Isuzu pulley?

If you have Mazde Edit, you may want to look into adjusting the throttle body positioning maps to more closely resemble a 1:1 pedal:throttlebody relationship, and let the Isuzu PCM sort out the rest.

_________________
Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.

The CEL lamp or LED is likely low side switched by the cluster electronics. I just have to open the cluster and cut the ground trace and route it outside of the cluster to the Isuzu ECU. I don't care about codes or lights on the RX8 ECU because I'm only using it as an interface to the canbus and for idle and throttle. I machined the Isuzu pulley to accept the RX8 reluctor wheel.

Another little tidbit. If you use the 2wd 98+ Isuzu automatic companion flange (from the 4L30E) it'll bolt up to the Solstice trans. Then use a Rodeo/Amigo/Trooper/ect driveshaft (both steel and aluminum available) you'll wind up with 1310 u-joints that you can couple to just about any differential. Cut to lenght and waalaa. If you use a Miata diff, use an RX7 flange (from the RX7 replacement drive shaft) and you'll have a Detroit 7260 yoke. Now use a '90 Dodge Datona front driveshaft u-joint, and you can couple the 7260 yoke to the 1310 Isuzu driveshaft.

I can't make this any easier for you guys!

Now that is one hell of a jigsaw puzzle. I'll give you a pass on having GM stuff in there, because it really does tend to be the glue of the car world.

_________________
Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.

Ended up going with '95 Rodeo parts. It's 1/2 of the 2 piece rear drive shaft off the Rodeo. This can now be changed to any length and contains a slip-joint.

That sounds like my front end...

For those ever considering the Solstice trans... 95 Rodeo 4x2 automatic hub. Cut 14.5mm off the end. Use Rodeo flange to adapt to 1310 ujoints.

I had considered buying a turbo Solstice engine package because they are so cheap, but I found the transmissions were the weak link. The gearing is improperly spaced and there's a large drop in revs plus many complain about how tough it is to shift. Not a snick, snick transmission like the Miata or S2000.

To me the transmission is more important than the engine. After driving multiple cars this summer if the transmission wasn't easy to use and came with the proper gear ratios it could turn a car that's good on paper into an also ran.

I like your idea in concept, but little things like this could ruin all the other work.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

I punched the numbers into the ratio calculator and liked how it looked. 1 2 and 3 are evenly spaced with a little wider gap to 4 and 5. If there's a large drop in revs, great! Let the torque do the work like a boosted car should. I hear they shift ok but I haven't actually driven a Solstice to know. As for power. It's based on the R154, which is a strong trans, but the 1 2 and 3 synchros are tripple-cone. There's also some treatment done to some gears but I forget which ones or what the treatment was. Maybe shot peened? This trans is also used in the Colorado and H3 hummer. In the Solstice they're bolting up LSx engines pushing 400hp through it without issues. Having been inside mine to correct a machining flaw with the shift forks, it looks pretty beefy in there compared to a Miata trans.

I finally got to drive another one today and it feels more like a V8 box than an import box. I didn't get to drive it terribly hard, but the rpm drops would lose you a lot of power. There's no replacement for revs, torque alone just simply won't do it.

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

That's the same misconception I hear again and again. If your torque curve is wider then your gear changes your fine. My torque curve should have more then 300 ft lbs over a 3000rpm spread. Wide gears are exactly what I want. As for the transmission. You can't expect a strong transmission to shift like a Civic. Strong transmissions have stronger gears that are physically larger and heavier (and well as the clutch disc) so you can't expect synchros to spin it all up as fast as they can smaller gears and clutches in little 4 banger cars. From what I've read, it's shifts well compared to a T5 or T56. The same trans was in my Amigo (AR5) and it felt pretty good for being an SUV. Let's just say I was expecting much less from it.