[Cyril_G 85]

Hello everyone, I haven't seen a "present yourself" forum, so I'll present myself and my project right here :

My name's Cyril, I'm 25 living in France near Nantes.
Currently owning a 205 Rallye that I completely rebuilt within 4 years.
I've also owned a NBFL Miata, that I sold for a TVR Wedge the reason of my subscription.

I bought this TVR in UK 3 years ago, in the middle of COVID and Brexit. This was quite the journey !!

Sadly after check-up in our workshop, the car is a mess. Frame is split in half at some parts. Coil-over and silentbloc are completely shot. The wiring is a fire hasard... But ! It had a race engine, a Rover V8 from an SD1, originally a 3.5l, now a 4.4 high compression, big valve, high flow head. Making around 300bhp.

I'm currently rebuilding the whole car, and looking to ditch the 14CUX, landRover original ECU. And replace it with an Speeduino of some sort.

And after watching the work of "@Ric355" which did an amazing job in its Chimaera, I'm looking to for some information and start guidelines to make this door stopper of a car a tru 80' spaceship !!

Thanks all in advance for your help !

P.S sorry if my English is not that great...

[jonbill]

Hi, sounds a fun project.
First thing, read the manual/wiki, it'll give you a sense of things you need to know and what questions you need answers to.

[Cyril_G 85]

Hi, sounds a fun project.

Already a lot of work done in term of engine, so adding a fully customisable ECU will surely be quite fun !

I'm currently looking at the DropBear board, but I can't seems to find why it's not available anymore, and if it will be ??

If it's caused by some components shortage I might be able to help as I'm working in the electronic industry.

Why the DropBear and not an 0.4.4 board ?
I'm looking to make this car upgradable as I go, maybe a supercharger, maybe methanol injection, surely FlexFuel... So starting with the most capable board I'm sure I won't be limited by hardware later.

[jonbill]

Yes, I believe dropbear is currently limited by teensy 3.5 availability. In the meantime, I think there are some other 8+8 boards available from others.

[Cyril_G 85]

Yes, I believe dropbear is currently limited by teensy 3.5 availability. In the meantime, I think there are some other 8+8 boards available from others.

That's what I thought, and if I understand correctly 4.0/4.1 board aren't compatible.

"Weirdly" an electronic shop in France seems to have more than 80pcs Teensy 3.5 board in stock !!
I'll call them to be sure, but maybe this can help the creator build new board if I can get them to him !

[Shuggy]

The Dropbear with Teensy 4.1 is about to be released.

I have a 4.6 TVR Chimera engine that I plan to use in a car I am building.

I plan to use Dropbear with new injectors later wasted spark coils Bosch EV14 injectors DIY EFI wideband 36-1 trigger with a cam sensor in the distributor.

Not sure about the trigger disc sensor or the idle control valve.

Happy to share ideas.

[PSIG]

Not sure about the trigger disc sensor or the idle control valve.

General response - the sensor should be chosen as one with ability to read small teeth on a small wheel at lower speeds. I would look for a sensor that can "see" the target well. Probably one rated as a "cam sensor". There are many examples on the forums of Hall types, but you may want to explore the newer xMR/GMR technology sensors becoming available. Some of them are very 'smart'. Oversimplified, they function similar to a Hall, but with potentially higher resolution.

VR typically require larger teeth, and while there may be some candidates, most will not qualify based on the size of your targets (teeth and gaps) combined with lower wheel speeds (½ crank speed).

The choices of IAC valve are many, but the original Rover V8 stepper IAC (effectively a traditional GM type) is a good candidate, and steppers generally tend to be more stable and predictable than floating-pintle PWM types. If it is not a choice, then more info of what type for what reasons would be helpful, to provide suggestions addressing your needs or concerns.

[Shuggy]

Thanks PSIG,

For the trigger sensor, my previous expreience was with a GT101 hall sensor (it was Motec recommended sensor for many years) https://uk.rs-online.com/web/p/hall-eff ... rs/2132762 is one source that is reliable and easy to obtain.

I was not aware of xMR/GMR technology sensors, a quick google thew a few options up, also TMR, but hard to be sure what the practical advantages are and of course there are no wiring schematics or details on the mating plugs that are easy to find.

I have attached an image of the 36-1 trigger wheel that I went with.

Do you have a recommended xMR/GMR sensor that also has wiring and connector details?

Interesting about the original Rover V8 stepper idle control valve being a good option, easy enough to stick with the standard option.

[PSIG]

I was not aware of xMR/GMR … but hard to be sure what the practical advantages are and of course there are no wiring schematics or details on the mating plugs that are easy to find.
Do you have a recommended xMR/GMR sensor that also has wiring and connector details?

No, I don't have any, as most of the options for a custom distributor setup will include a custom sensor element (making a sensor mount or housing). Examples of these are on these forums, and include threaded housings, sensors on PCB mounts, etc, as appropriate constructed sensor assemblies to fit and function well inside the distributor housing. I of one where they simply glued a tiny sensor element to a points set to read a tiny wheel.

Although it is obsolete and not produced anymore, the GT101 could be suitable if you can find one, but tends to need larger tooth profiles to read correctly... Check this in their datasheets. Likewise, other built sensor assemblies such as the ZF/Cherry GS100701 are very popular in-general, but again are generally intended for larger crank wheels and bigger target teeth and angles, perhaps larger than yours. Again, check the spec's against your wheel with the datasheets.

This was why I mentioned GMR, as little transistor-size units are available for you to make a suitable mount for, and many of them can read much smaller teeth at lower speeds. I'm not saying it's the answer - just an option for a possible solution to mount in your distributor housing and read the teeth you have. No one has done exactly what you are doing with exactly the parts you have, so packaged solutions may be very limited that fit the application. It's not difficult, but it will take some effort. Good luck!

Creating a simple mount for a tiny device such as this, that meets all your other spec's, may be easier than looking for a pre-packaged unit:

3-pin_SIP_sensor.jpg (3.62 KiB) Viewed 2412 times

[PSIG]

Why the DropBear and not an 0.4.4 board ?
I'm looking to make this car upgradable as I go, maybe a supercharger, maybe methanol injection, surely FlexFuel... So starting with the most capable board I'm sure I won't be limited by hardware later.

Just a passing alternative comment on this line of thought. My suggestion is to use what you know you can use today or very soon. There are many power-adder engines running great on 2x4 and 4x4 boards, and most users never tune or use the per-channel functions anyway. You know it will do what you need, today, and for lower cost.

But more than that - by the time you get around to requiring more than that capability, and know exactly what that is, newer versions and new capabilities for 8x8 boards will be available. Do you want to jump so soon towards today's versions and miss or double-spend that opportunity? I only mention this as I have several ECMs here that I never used, as by the time I could use them, I needed or wanted something better or different. Just sharing my expensive experience.