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Re: Mk1 MG hill climb racer
Posted: Fri Jun 09, 2017 12:13 pm
by Artstu
DotMatrix wrote: ↑Fri Jun 09, 2017 10:47 am
that looks good. its a much more modern dash in such a car I see
do you have a link to that speedo?
Yes it's a slightly reworked Midas mk2 dash. here's the speedo thread
http://midasownersclub.co.uk/forums/vie ... eedo#p4338
Re: Mk1 MG hill climb racer
Posted: Fri Jun 09, 2017 9:01 pm
by DotMatrix
a bit expensive those digital speedometers, but nice that you can get them in 100mm which is the diameter of the hole in the instrument panel so you don't need to make a mounting plate as I did because my tachometer is 80mm in diameter. I like his solution as it gives him an odometer and a speedometer where a simple gps wouldn't.
I can read that the speedo gets its reading from two magnets and a sensor attached to the drive shaft, it would be nice to see how he did that.
When ever I have looked for a digital speedo I have been looking to get a sensor that would mount in the standard hole in the gearbox because I like the idea of the standard position and mounting on something that doesn't rotate, but I have found that this will almost certainly mean that I would have to do some electronics calculating and soldering which will be more expensive and more time consuming.
Re: Mk1 MG hill climb racer
Posted: Sat Jun 10, 2017 6:19 pm
by KLAS
digital speedo is quite easy with the A-series. just put a sensor where the cable is usually screwed on. most sensors use metric M18x1.5 threads so you have to change the thread of the gearbox.
VDO used to make a couple of types, direct screw on with cable output and without cable output, and remote to fit anywhere to the cable. you cut the cable, put on some adaptors, and refit all together. the last one was mostly used for aftermarket navigation systems when the car didn't had a digital speedo signal.
as you don't need a cable you may look at the Rover 200 and 400 sensor, they can be found quite cheap.
or even simpler, use
http://minispares.com/product/Classic/G ... D1001.aspx
just have to check if the square drive pin has the correct size
Re: Mk1 MG hill climb racer
Posted: Sat Jun 10, 2017 9:45 pm
by DotMatrix
KLAS wrote: ↑Sat Jun 10, 2017 6:19 pm
digital speedo is quite easy with the A-series. just put a sensor where the cable is usually screwed on. most sensors use metric M18x1.5 threads so you have to change the thread of the gearbox.
VDO used to make a couple of types, direct screw on with cable output and without cable output, and remote to fit anywhere to the cable. you cut the cable, put on some adaptors, and refit all together. the last one was mostly used for aftermarket navigation systems when the car didn't had a digital speedo signal.
as you don't need a cable you may look at the Rover 200 and 400 sensor, they can be found quite cheap.
or even simpler, use
http://minispares.com/product/Classic/G ... D1001.aspx
just have to check if the square drive pin has the correct size
great info klas! and either of those two speedo drives gives the right kind of pulses for a digital speedo?
Re: Mk1 MG hill climb racer
Posted: Sun Jun 11, 2017 12:32 pm
by KLAS
they give out a square wave signal, basically what all Hall effect sensors give out. they may have differend numbers of inpulses per revolution, but most aftermarket speeedos are programmable to show the correct speed with whatever number of impulses.
so if the speedo you would like to use requires a Hall effect sensor and doesn't specify a specific number of impulses per kilometer/mile it should work
Re: Mk1 MG hill climb racer
Posted: Mon Jun 19, 2017 11:21 pm
by DotMatrix
I spent all week last week fixing and checking all sorts of things with this car in order to get it ready for the race this last weekend. I had a lot of strange new troubles, but I managed to get it kind-of fixed. in this picture I am measuring the cam timing for the 10'th time and it turned out that it was set right, so the 3 hp I am missing and the nm I have gained must be a result of the lower compression somehow.
I spent a lot of time trying to get the engine to rev to 7500rpm like it used to do, checked the dizzy (mechanically), coil, leads and electrical connections and everything seems fine, I managed to fix the rev problem by setting the timing to 26 degrees of total timing instead of 29 where it actually makes the most power, but wont rev higher than about 6000-6500rpm. Its funny how every problem I fix seems to reveal a new one I haven't tried before

Re: Mk1 MG hill climb racer
Posted: Mon Jun 19, 2017 11:22 pm
by DotMatrix
KLAS wrote: ↑Sun Jun 11, 2017 12:32 pm
they give out a square wave signal, basically what all Hall effect sensors give out. they may have differend numbers of inpulses per revolution, but most aftermarket speeedos are programmable to show the correct speed with whatever number of impulses.
so if the speedo you would like to use requires a Hall effect sensor and doesn't specify a specific number of impulses per kilometer/mile it should work
thanks for the info. this makes looking for a speedo a lot easier.
Re: Mk1 MG hill climb racer
Posted: Mon Aug 07, 2017 10:26 pm
by DotMatrix
Re: Mk1 MG hill climb racer
Posted: Mon Aug 14, 2017 9:03 pm
by DotMatrix
no pictures right now, but I had a very nice weekend with racing both saturday and sunday and apart from me changing a leaking waterpump gasket saturday no problems at all and the switch to turn on the electric fan I made was also great.
we had a lot of rain during the afternoon saturday so that ofcourse meant lots of water in the bottom of this car as it comes through the bulkhead somewhere, anyway it wasn't a problem as I haven't removed the heater and fan yet (no water running through the heater though, but the air was enough to clear the fog on the windshield. I was considering removing the fan motor and ducting inside the car but wont remove the fan now af this. might remove the heater and do some ducting my self though.
anyway I didn't make any mistakes this time

but I did remember to take some video that I will be uploading as soon as I have edited them.
Re: Mk1 MG hill climb racer
Posted: Sat Aug 26, 2017 8:35 pm
by DotMatrix
came first in my class at todays race! very pleased with that

the car drove great and it was a real tight twisty track which suits me and the car great
