In need of a Repro Tach

[CudaJon]

I have come to the conclusion that my 73 Cuda Tach  for a Rallye gauage is a basket case and I don't have the skill set to clean or redo the spring mechanism.  Can the group recommend manufacturers who sell Repro Tachs or at least ones to stay away from.   This would help tremendously since there seems to be a lot out there. Big Thanks!!!

[jason340]

Dave@ Performance Graphics rebuilds, restores gauges, speedos and tachs. He did great work on my rallye clock with a quick turnaround.

[CudaJon]

Thanks but I'm looking for a turn key repro to replace my.

[jason340]

Year One had them.

[CudaJon]

There are a number of companies that have repro's I'm just looking for any recommendation from anyone that had previous purchased one and was happy or NOT!

[dodj]

rt.eng has a kit
http://rt-eng.com/rte/index.php/Main_Page

[CudaJon]

Yes I did purchase the RT eng board in fact it works great but that's when I learned my movement - shaft and jewel are shot so I'm turning to a repro as opposed for a rebuilt.

[Mpdlawdog]

Year one and put ebody in the coupon part...saved 15%...ended up being about $200

[tman]

Don't forget Dave at Roseville.  He offers discounts and meets or beats others pricing.

[CudaJon]

Yep! Ordered Tach from Roseville couple of days ago, coming in next week.  Using a signal generator I can now simulate the signal from the coil.  Thanks!

[Mpdlawdog]

Yep! Ordered Tach from Roseville couple of days ago, coming in next week.  Using a signal generator I can now simulate the signal from the coil.  Thanks!

I'd much rather order from dave...what did he charge you for the tach??  I have to ask what is a signal generator and how does it work??

[CudaJon]

So the total cost plus shipping was about 225. I have my original to compare cosmically and was told if I don't like it I can send it back for a full refund as long as it's not installed.  So a signal generator can produce or generate a signal that replicates the signal from the coil so I can verify functionality on the bench. All I need is 12 Volts and the generator.    The generator can produce with the user pushing buttons on the front panel any sort of signal at any freq at any amplitude within the specs of the SG.  So I know that the signal is a pulse so that looks like a square wave and the amplitude is 5-6 volts with the duty cycle (on/off of the pulse) at 50%. So it pulses 'on' for the same time it pulses 'off'.  The freq determines the rate of duty cycle or in our case the simulated RPM. I don't have my notes in front of me but for say 267Hz which is cycle per sec, one times that by 60 for minutes than divide by 8 for number of cylinders and  then multiply by 4 for stroke fired on 1 firing stroke and divide by 2 for 1 firing stroke for 2 cycles.  I'm rereading  and I hope this makes sense.

Thanks for all the input!!!

[Mpdlawdog]

So the total cost plus shipping was about 225. I have my original to compare cosmically and was told if I don't like it I can send it back for a full refund as long as it's not installed.  So a signal generator can produce or generate a signal that replicates the signal from the coil so I can verify functionality on the bench. All I need is 12 Volts and the generator.    The generator can produce with the user pushing buttons on the front panel any sort of signal at any freq at any amplitude within the specs of the SG.  So I know that the signal is a pulse so that looks like a square wave and the amplitude is 5-6 volts with the duty cycle (on/off of the pulse) at 50%. So it pulses 'on' for the same time it pulses 'off'.  The freq determines the rate of duty cycle or in our case the simulated RPM. I don't have my notes in front of me but for say 267Hz which is cycle per sec, one times that by 60 for minutes than divide by 8 for number of cylinders and  then multiply by 4 for stroke fired on 1 firing stroke and divide by 2 for 1 firing stroke for 2 cycles.  I'm rereading  and I hope this makes sense.

Thanks for all the input!!

interesting...that some complicated stuff there!  Im amazed you could find the rate of cycle to match our RPM's and the break down from there!  I always wondered how they calibrated a tach while it was out of the car