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The Buchka 242 Daily Driver

Some of it is very simple, other parts are more complicated.

The warning lights, indicators, and backlight are all just piped out to the back connector, so making them work is just a case of connecting the correct wires in the car. I designed a circuit board that makes it plug-and-play:
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We modified the thermostat housing to accept a CBR1000RR coolant temperature sensor. That is wired straight to the cluster to show coolant temp:
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The speedo and tach are a bit more convoluted. The tach expects 2 pulses per engine revolution to show the correct RPM. The megasquirt can only output either 1.5 or 3 pulses per revolution with this engine. The speedometer shows 10KPH per 100Hz, which translates in to a ~70.4 tooth tone ring on the rear diff. Obviously neither of these things are even close to lining up.

I was hoping to hack the firmware on the cluster to re-calibrate it, but that proved to be beyond my patience. Instead we opted to put a frequency multiplier/divider in line with both signals. It's just a small circuit board with a microcontroller that lives inside the instrument cluster and correctly re-scales the input signals.

Many thanks! I suspect most ECUs expect a simple square wave for the speedo? Probably fairly simple to grab ye olde function generator and work out the calibration. Regardless, very cool idea and execution.
 
The new MS firmware can scale the tach output as needed (at least on my MS3x).

That's a good point, but it's only an MS3 feature. MS2 still only offers half speed or full speed output. I know Alex wants to go MS3 down the line for this car, so that would be a good time to move that function in to the ECU.

Many thanks! I suspect most ECUs expect a simple square wave for the speedo? Probably fairly simple to grab ye olde function generator and work out the calibration. Regardless, very cool idea and execution.

It's hard to make a general statement about which speedos require what. 240/740/940 speedos all take a VR input straight from the sensor in the rear axle. We bought a hall-effect sensor for Alex's car that will be triggered off the bolts holding the rear drive-shaft to the pinion.

Either way, any decent function generator will be able to generate both square waves and sine waves, so finding the calibration is simple. That's how we determined what the CBR cluster looks for.
 
You guys are insane.

Seriously.

I see build threads on other forums where guys do unconventional engine swaps and everybody loses thier ****. If they saw this stuff, I don't even think they'd be able to comprehend it. You guys made some badass custom wheels, put in a badass engine, made your own wiring harness, and make your own circuit boards ffs.

This is consistiently one of the most technically amazing builds I read. Consistiently.
 
You guys are insane.

Seriously.

I see build threads on other forums where guys do unconventional engine swaps and everybody loses thier ****. If they saw this stuff, I don't even think they'd be able to comprehend it. You guys made some badass custom wheels, put in a badass engine, made your own wiring harness, and make your own circuit boards ffs.

This is consistiently one of the most technically amazing builds I read. Consistiently.

Thanks man, I really appreciate it. Both Karl and I have really put in quite a bit of effort on the car. Having access to the right tools definitely helps.

Nice work. One small word of advice I have been given after doing a similar brake setup, make vent holes in the hat between the bolts.

Thanks for the heads up. I perused some AP Racing data sheets and they do recommend additional slots in the hats to provide cooling air to the outside face of the rotor. I put the hats back on the mill and machined some channels between the bobbin holes.

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If I had these tools at my disposal, I would be doing pretty much everything you are. Seriously, it sometimes feels like you're in my head. Kudos for not only making it happen, but taking the time and money to make it happen the right way.
 
If I had these tools at my disposal, I would be doing pretty much everything you are. Seriously, it sometimes feels like you're in my head. Kudos for not only making it happen, but taking the time and money to make it happen the right way.

I think you're forgetting two major components here... talent and skill.

Tools aren't what make this project(and their other projects) great--it's the people behind them.
 
I think you're forgetting two major components here... talent and skill.

Tools aren't what make this project(and their other projects) great--it's the people behind them.
The talent and skill are implied with these guys, those two factors are blatantly obvious. I've been on a few projects where I did the designing but had to farm out the machine work; it's... frustrating.
 
The talent and skill are implied with these guys, those two factors are blatantly obvious. I've been on a few projects where I did the designing but had to farm out the machine work; it's... frustrating.

I've seen people build really impressive stuff with ancient machines and people build mediocre crap with the latest and greatest stuff.

Not saying you don't have talent by any means, just saying that in my experience, skill trums tools. Because if you know what you're trying to do and how to do it, you can figure out an alternative. Whereas if you don't know what processes or tools you need to get to your end result, you're probably gonna make crap.

Case in point, the Buchka 240 to CBR dash adapter... I would not in a million years think up a way to make that a PCB that nicely plugs everything together. Best I could probably come up with would be to get a pinout of each and try to figure out how to splice them together -- and what I'd end up with is probably a huge nasty mess of wires and a burnt out cluster.

Inversely I'm sure even if these two didn't have the tools to make the stuff they do, they could still produce a lot higher quality stuff than most of TB.
 
I'll just leave this here.

<iframe width="640" height="360" src="https://www.youtube.com/embed/4bkb7QlJbYg?rel=0" frameborder="0" allowfullscreen></iframe>
 
I've been to their shared shop in CA where this car was mostly built. They didn't have anything I was impressed with tool wise. A lift and an old small lathe were probably the 2 biggest things that most people don't have. They seem to make due with whatever they have and use of friend hook ups for tools/machines they don't, just like the majority of us.
 
All good guesses. I haven't opened the axle yet but I'm pretty sure I shredded the spiders in the stock open diff. Going to install a G80 I have laying around as an interim just to get the car mobile again. I just got a decent condition powerlok that will go into a freshened and re-geared stock axle, I'll be building that up over the next few months or so.
 
All good guesses. I haven't opened the axle yet but I'm pretty sure I shredded the spiders in the stock open diff. Going to install a G80 I have laying around as an interim just to get the car mobile again. I just got a decent condition powerlok that will go into a freshened and re-geared stock axle, I'll be building that up over the next few months or so.

I thought a lsd was already installed. That sounds just like one of the open diffs ive shreded. Any material through the cover?
 
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