Hello from Canada

[Tire guy]

Hi all, I've been lurking on here occasionally. So my goal is to design a new board with 2 canbus, internal O2 and knock control so I can run my...
jk jk no new hardware, there's enough already. Not that I'm capable of designing one either. I'm no EE, also useless in coding But I am looking forward to adding to a list of engines/cars successfully running rusefi.
There's MRE kit on it's way to me so that's where i'm gonna start.

Looking at wiring/pinout at https://github.com/rusefi/rusefi/wiki/Hardware_microRusEfi_wiring
Low side general purpose such as pin 3 or 7 can also drive an injector, right. And GP1 push-pull 5volt pins 13 or 14 can drive an ignition coil? What are the chances that MRE is capable of running a 5 cylinder engine?

Stay at home, be safe ya'll

[AndreyB]

jk jk no new hardware, there's enough already

So you've seen a couple of threads here

Welcome to the forum!

[mck1117]

jk jk no new hardware, there's enough already.

Looking at wiring/pinout at https://github.com/rusefi/rusefi/wiki/Hardware_microRusEfi_wiring
Low side general purpose such as pin 3 or 7 can also drive an injector, right. And GP1 push-pull 5volt pins 13 or 14 can drive an ignition coil? What are the chances that MRE is capable of running a 5 cylinder engine?

Two important questions first:

1. Volvo, Audi, or Mercedes?
2. How many turbos?

The chances of running it are very good! I don't think rusEfi has yet run a real 5 cylinder, but we have run 1, 3, 4, 6, 8 and 12, with bench testing of a 5cyl that looks correct.

You're correct that pins 13/14 can drive an ignition coil - by they're identical to the 4 "normal" ignition outputs (if you don't move a jumper). So ignition is easy to handle.

For fuel, you could use the four injector channels, plus one of the lowsides (pin 3 or 7). The injector connected to the lowside would likely open very slightly faster so it would get the tiniest bit more fuel, but it's probably not enough to cause a problem.

[Tire guy]

Good to hear it's doable!
It's audi 7A 2.3L N/A. Trigger setup is same or similar as 3B, AAN and other 2.2 turbos.
crank VR with 135 teeth on the flywheel.
cam hall with a slit(gap) in a disc inside the distributor.
We're going with audi cops (R8 coils) and of course getting boosted. Only one turbo
will stay with cable throttle for now but, definitely want to experiment with dbw

[mck1117]

It's audi 7A 2.3L N/A. Trigger setup is same or similar as 3B, AAN and other 2.2 turbos.
crank VR with 135 teeth on the flywheel.
cam hall with a slit(gap) in a disc inside the distributor.

I assume that 135 teeth is the starter ring, and the trigger is a normal 60-2 like every other Bosch setup on the planet. That setup should work fine - have MRE tested on BMWs, Volvos, and Audis with the standard Bosch 60-2 VR setup, and it works great.

We're going with audi cops (R8 coils) and of course getting boosted. Only one turbo
will stay with cable throttle for now but, definitely want to experiment with dbw

Sounds great!

[Tire guy]

I assume that 135 teeth is the starter ring

yes

trigger is a normal 60-2 like every other Bosch setup on the planet.

no unfortunately, I wish it was normal. The flywheel also has a dowel pin in it (some versions have two), and its own vr sensor next to bellhousing. So yes, 2 sensors just for the crank. One reads starter ring teeth, and because they're all evenly spaced, there's a second sensor triggered by the pin once per revolution.
I wish to do without the stupid pin sensor; vr reading 135 teeth and hall on the cam. I sense it hasn't been done yet


picture borrowed from https://www.audiworld.com/forums/audi-original-s-cars-25/g4-crank-position-sensor-g28-engine-speed-sensor-maintenance-2864533/

[mck1117]

no unfortunately, I wish it was normal. The flywheel also has a dowel pin in it (some versions have two), and its own vr sensor next to bellhousing. So yes, 2 sensors just for the crank. One reads starter ring teeth, and because they're all evenly spaced, there's a second sensor triggered by the pin once per revolution.
I wish to do without the stupid pin sensor; vr reading 135 teeth and hall on the cam. I sense it hasn't been done yet

Agh - that's a hassle then. Adding that trigger pattern is likely possible, but some care would need to be taken as that's over double the most teeth ever run on rusEfi. Are there other trigger options for your engine? How hard would it be to add a 36-1 or 60-2 to the front with a hall or VR sensor?

[Tire guy]

I've been looking into options already. Some people have had mixed results with front trigger setups, some of them custom diy, some were offered by companies. Other option is rear main seal with trigger wheel and sensor built in. They came on some older 4 cyl gas and diesel engines in europe. They're 60-2 hall. probably my best bet

[puff]

afaik, these also fit audi's 5-cyl engines from late 80-s - early 90-s? but! people say, there are some problems with mounting the sensor (cutting the bell?) + how easy would it be to replace that sensor in case it fails? anyways, would be nice to see pictures of how you coped with it.

[mck1117]

They're 60-2 hall. probably my best bet

I agree - that's a good bet. 60-2 is very well supported. If you're already going to have the engine out, seems like an easy option to put in place.

[Tire guy]

afaik, these also fit audi's 5-cyl engines from late 80-s - early 90-s? but! people say, there are some problems with mounting the sensor (cutting the bell?) + how easy would it be to replace that sensor in case it fails? anyways, would be nice to see pictures of how you coped with it.

from what I read, the sensor is impossible to remove/install while seal is in place. You have to install sensor into seal housing, then install that onto the engine. Of course it's a pain in the back to get to it so I hope it doesn't fail . When I get closer, I'll create a thread and keep you updated.

newb question: can MRE handle 2 injectors and 2 coils per channel in wasted/batch mode to run 6 or 8 cylinder engine? Or is that too much current draw for this unit?

[AndreyB]

Smart coils are not a concern but 6-8 injectors are at the edge for current for current schematics.