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Tic toc tach accuracy #1743434 01/31/15 07:48 PM 01/31/15 07:48 PM
Joined: Nov 2014 Posts: 32 Santa Barbara, California E Edahlke OP member
Edahlke OP member E Joined: Nov 2014 Posts: 32 Santa Barbara, California	Hi all, I just installed the tic toc Tach into my 68 charger 440. Install was pretty simple, just power and the negative output from the coil. I have the mopar performance electronic ignition installed as well. With the engine idling, the tach reads 0. It does increase as I give it gas, however the reading is always low. I was under the impression the tach would work fine with the mopar electronic ignition. Is this true? Are these tachs just not very accurate?

Re: Tic toc tach accuracy [Re: Edahlke] #1743435 01/31/15 07:54 PM 01/31/15 07:54 PM
Joined: Jan 2003 Posts: 5,439 So Cal Sinitro master
Sinitro master Joined: Jan 2003 Posts: 5,439 So Cal	Are U running a stepup electronic ignition box? If yes, the OE Mopar tach will not read accurately.. Just my $0.02...

Re: Tic toc tach accuracy [Re: Sinitro] #1743436 01/31/15 09:35 PM 01/31/15 09:35 PM
Joined: Jan 2003 Posts: 10,702 North Dakota 6PakBee I Live Here
6PakBee I Live Here Joined: Jan 2003 Posts: 10,702 North Dakota	Quote: Are U running a stepup electronic ignition box? If yes, the OE Mopar tach will not read accurately.. Just my $0.02... What is a electronic ignition? Mopar electronic? Pertronix? MSD? All of the above? ????? "We live in a time when intelligent people are being silenced so that stupid people won't be offended".

Re: Tic toc tach accuracy [Re: 6PakBee] #1743437 01/31/15 11:33 PM 01/31/15 11:33 PM
Joined: Jan 2003 Posts: 5,439 So Cal Sinitro master
Sinitro master Joined: Jan 2003 Posts: 5,439 So Cal	Quote: Quote: Are U running a stepup electronic ignition box? If yes, the OE Mopar tach will not read accurately.. Just my $0.02... What is a electronic ignition? Mopar electronic? Pertronix? MSD? All of the above? ????? All of the above... Beyond a standard points system.. Just my $0.02..

Re: Tic toc tach accuracy [Re: Edahlke] #1743438 01/31/15 11:49 PM 01/31/15 11:49 PM
Joined: Feb 2012 Posts: 199 NC 1 1970A66 member
1970A66 member 1 Joined: Feb 2012 Posts: 199 NC	The tach will work fine with Mopar electronic ignition. It does on my 70 Challenger. Those factory tach circuit boards are NOT accurate. Also the tach needle is press fit on and should read zero with the ignition key off. Your tach has 2 parts: 1)the meter movement and 2) the circuit board. Either one could cause your problem. This is the best option for new circuit boards: http://rt-eng.com/rte/index.php/Main_Page There are 2 67-74 boards. The more expensive has an on-board calibrator ckt. Is your needle on zero with the car shut off? If so then I think your board is most likely bad. They have capacitors that often fail. But it could be a dirty/sticking meter movement causing the needle to remain on zero until you rev it to get it un-stuck.

Re: Tic toc tach accuracy [Re: Edahlke] #1743439 01/31/15 11:55 PM 01/31/15 11:55 PM
Joined: Feb 2012 Posts: 199 NC 1 1970A66 member
1970A66 member 1 Joined: Feb 2012 Posts: 199 NC	http://www.forbbodiesonly.com/moparforum/showthread.php?61170-Factory-Tach-with-Electronic-Ignition

Re: Tic toc tach accuracy [Re: 1970A66] #1743440 02/01/15 03:17 AM 02/01/15 03:17 AM
Joined: Jun 2008 Posts: 1,822 Colorado D denfireguy top fuel
denfireguy top fuel D Joined: Jun 2008 Posts: 1,822 Colorado	Quote: http://www.forbbodiesonly.com/moparforum/showthread.php?61170-Factory-Tach-with-Electronic-Ignition There is some confusion in that thread and it stems from the different types of electronic ignitions. Mopars ignition system using the black box, orange box, chrome box, etc. uses a reluctor to replace point signaling and a large transistor switch to ground the coil to start the spark sequence. As a result, the switching voltages are the same as the old points system so there is no difference in tach signals. MSD, Mallory and others are what use to be called capacitive discharge systems. They use an inverter to generate around 400 volts to discharge through the coil with a charged capacitor and attaching a tach without the adaptor will destroy the factory tach. IF it did not destroy the tach, it would also be inaccurate as most of them employ multi-spark events on each plug firing at low speeds to insure fuel burn. The adaptor for the tach solves both of those issues. Craig 2014 Ram 1500 Laramie, 73 Cuda Previous mopars: 62 Valiant, 65 Fury III, 68 Fury III, 72 Satellite, 74 Satellite, 89 Acclaim, 98 Caravan, 2003 Durango Only previous Non-Mopar: Schwinn Tornado

Re: Tic toc tach accuracy [Re: denfireguy] #1743441 02/02/15 05:33 PM 02/02/15 05:33 PM
Joined: Jan 2003 Posts: 5,439 So Cal Sinitro master
Sinitro master Joined: Jan 2003 Posts: 5,439 So Cal	Quote: There is some confusion in that thread and it stems from the different types of electronic ignitions. Mopars ignition system using the black box, orange box, chrome box, etc. uses a reluctor to replace point signaling and a large transistor switch to ground the coil to start the spark sequence. As a result, the switching voltages are the same as the old points system so there is no difference in tach signals. Incorrect... An OE Mopar tach (up to 71) will not read accurately with a Mopar electronic ignition, electronic distributor w/orange, chrome or gold box. The tach will indicate some RPM level but it is not accurate. Regarding other aftermarket systems, Mallory, Pertronix, MSD U better check with the respective manufacturer about compatibility with the various tachs be it OE or aftermarket.. As some external dongle adapter may be required. Just my $0.02..

Re: Tic toc tach accuracy [Re: Sinitro] #1743442 02/03/15 12:16 PM 02/03/15 12:16 PM
Joined: Jun 2008 Posts: 1,822 Colorado D denfireguy top fuel
denfireguy top fuel D Joined: Jun 2008 Posts: 1,822 Colorado	My mistake not addressing accuracy. I was only talking about the proper voltages and damage to the tach itself. Just to clarify, the voltages present with capacitive discharge systems are too high for factory tachometers to handle and will result in permanent damage. Conventional Mopar systems, points or electronic, will not damage the tach. It still may not read right as the wave forms are not what the tach expected. Dwell on points systems was usually much longer and adjustable. On electronic systems, while somewhat adjustable by adjusting reluctor gap, it is much shorter and presents a different duty cycle to the tach than it was expecting. Craig 2014 Ram 1500 Laramie, 73 Cuda Previous mopars: 62 Valiant, 65 Fury III, 68 Fury III, 72 Satellite, 74 Satellite, 89 Acclaim, 98 Caravan, 2003 Durango Only previous Non-Mopar: Schwinn Tornado

Re: Tic toc tach accuracy [Re: denfireguy] #1743443 02/03/15 01:31 PM 02/03/15 01:31 PM
Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada D DPelletier I Live Here
DPelletier I Live Here D Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada	OK, for those of us running the Mopar electronic distributor and orange box, can you make the factory tach read accurately? Dave 1970 Super Bee 440 Six Pack 1974 'Cuda 2008 Ram 3500 Diesel 2006 Ram 3500 Diesel 2004.5 Ram 2500 Diesel 2003 Ram 3500 Diesel 2006 Durango Limited [url] http://1970superbee.piczo.com [/url]

Re: Tic toc tach accuracy [Re: DPelletier] #1743444 02/03/15 05:03 PM 02/03/15 05:03 PM
Joined: Jan 2003 Posts: 5,439 So Cal Sinitro master
Sinitro master Joined: Jan 2003 Posts: 5,439 So Cal	Quote: OK, for those of us running the Mopar electronic distributor and orange box, can you make the factory tach read accurately? Dave No... On my 70RR, I swapped out the Tic/Tac for a tach using the VDO insides from RedLine. RedLine custom makes a front plate using the same fonts as the OE Mopar so it matches the other guages. My ignition system is the Mopar electronic distributor and chrome box. I also have run an MSD box without issues except the tach is driven from the MSD box rather than the coil. Just my $0.02...

Re: Tic toc tach accuracy [Re: Sinitro] #1743445 02/03/15 06:48 PM 02/03/15 06:48 PM
Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada D DPelletier I Live Here
DPelletier I Live Here D Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada	Quote: Quote: OK, for those of us running the Mopar electronic distributor and orange box, can you make the factory tach read accurately? Dave No... On my 70RR, I swapped out the Tic/Tac for a tach using the VDO insides from RedLine. RedLine custom makes a front plate using the same fonts as the OE Mopar so it matches the other guages. My ignition system is the Mopar electronic distributor and chrome box. I also have run an MSD box without issues except the tach is driven from the MSD box rather than the coil. Just my $0.02... Thanks but I already paid $425 for the tach from Charger Specialties (plus duty, shipping and exchange so probably really about $750.00). I can't see ripping it apart and paying another $300 - $400 so I guess I'll just go by ear for now. ....maybe a hidden rev limiter for safety.. Dave 1970 Super Bee 440 Six Pack 1974 'Cuda 2008 Ram 3500 Diesel 2006 Ram 3500 Diesel 2004.5 Ram 2500 Diesel 2003 Ram 3500 Diesel 2006 Durango Limited [url] http://1970superbee.piczo.com [/url]

Re: Tic toc tach accuracy [Re: DPelletier] #1743446 02/03/15 08:04 PM 02/03/15 08:04 PM
Joined: Jan 2003 Posts: 5,439 So Cal Sinitro master
Sinitro master Joined: Jan 2003 Posts: 5,439 So Cal	Quote: Quote: Quote: OK, for those of us running the Mopar electronic distributor and orange box, can you make the factory tach read accurately? Dave No... On my 70RR, I swapped out the Tic/Tac for a tach using the VDO insides from RedLine. RedLine custom makes a front plate using the same fonts as the OE Mopar so it matches the other guages. My ignition system is the Mopar electronic distributor and chrome box. I also have run an MSD box without issues except the tach is driven from the MSD box rather than the coil. Just my $0.02... Thanks but I already paid $425 for the tach from Charger Specialties (plus duty, shipping and exchange so probably really about $750.00). I can't see ripping it apart and paying another $300 - $400 so I guess I'll just go by ear for now. ....maybe a hidden rev limiter for safety.. Dave Dave.. The tachs from Charger Specialties have later internal electronics in them, so they are compatible with the older point systems, Mopar electronic systems, MSD and most aftermarket ignition systems. Just my $0.02...

Re: Tic toc tach accuracy [Re: Sinitro] #1743447 02/03/15 09:40 PM 02/03/15 09:40 PM
Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada D DPelletier I Live Here
DPelletier I Live Here D Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada	Quote: Quote: Quote: Quote: OK, for those of us running the Mopar electronic distributor and orange box, can you make the factory tach read accurately? Dave No... On my 70RR, I swapped out the Tic/Tac for a tach using the VDO insides from RedLine. RedLine custom makes a front plate using the same fonts as the OE Mopar so it matches the other guages. My ignition system is the Mopar electronic distributor and chrome box. I also have run an MSD box without issues except the tach is driven from the MSD box rather than the coil. Just my $0.02... Thanks but I already paid $425 for the tach from Charger Specialties (plus duty, shipping and exchange so probably really about $750.00). I can't see ripping it apart and paying another $300 - $400 so I guess I'll just go by ear for now. ....maybe a hidden rev limiter for safety.. Dave Dave.. The tachs from Charger Specialties have later internal electronics in them, so they are compatible with the older point systems, Mopar electronic systems, MSD and most aftermarket ignition systems. Just my $0.02... Thanks, I was wondering about it's accuracy and I ASSuMEd that it was an accurate repop of the originals...I'll maybe check it with a friends spare from his racecar but sounds like I may be good to go! Dave 1970 Super Bee 440 Six Pack 1974 'Cuda 2008 Ram 3500 Diesel 2006 Ram 3500 Diesel 2004.5 Ram 2500 Diesel 2003 Ram 3500 Diesel 2006 Durango Limited [url] http://1970superbee.piczo.com [/url]

Re: Tic toc tach accuracy [Re: Edahlke] #1743448 02/03/15 10:06 PM 02/03/15 10:06 PM
Joined: May 2008 Posts: 452 new york usa P pattyboy 572 mopar
pattyboy 572 mopar P Joined: May 2008 Posts: 452 new york usa	This kit will convert any tic toc tach...I had a 1970 original, install a original mopar dist w/orange box accuracy was destroyed,this corrected it...easy to install...but if you purchased one of the newer repos this is not required..as mentioned http://premiumdashdecals.com/support/instructions_exact_reproduction_TB-OEM.pdf Last edited by pattyboy 572; 02/03/15 10:07 PM.

Re: Tic toc tach accuracy [Re: DPelletier] #1743449 02/03/15 10:06 PM 02/03/15 10:06 PM
Joined: Nov 2007 Posts: 21,819 Kirkland, Washington Pacnorthcuda Too Many Posts
Pacnorthcuda Too Many Posts Joined: Nov 2007 Posts: 21,819 Kirkland, Washington	i upgraded a factory Cuda ralley tach with the modern digital board only to find out that the factory movements from the period are very heavy (slow) compared to the aftermarket or modern techs we're used too. They can be fine for reading steady state cruise rpms but upon fast acceleration they can be brutally slow, lagging behind the true RPM by hundreds. Not good for getting an idea on shift points. I ended up mounting an aftermarket tach right in front of it.

Re: Tic toc tach accuracy [Re: 1970A66] #1743450 02/04/15 01:17 AM 02/04/15 01:17 AM
Joined: Nov 2008 Posts: 1,491 Lethbridge, AB, Canada dangina pro stock
dangina pro stock Joined: Nov 2008 Posts: 1,491 Lethbridge, AB, Canada	Quote: The tach will work fine with Mopar electronic ignition. It does on my 70 Challenger. Those factory tach circuit boards are NOT accurate. Also the tach needle is press fit on and should read zero with the ignition key off. Your tach has 2 parts: 1)the meter movement and 2) the circuit board. Either one could cause your problem. This is the best option for new circuit boards: http://rt-eng.com/rte/index.php/Main_Page There are 2 67-74 boards. The more expensive has an on-board calibrator ckt. Is your needle on zero with the car shut off? If so then I think your board is most likely bad. They have capacitors that often fail. But it could be a dirty/sticking meter movement causing the needle to remain on zero until you rev it to get it un-stuck. this is awesome! I didn't even know about these guys! now I know where to buy the stuff when I have problems - props to you!

Re: Tic toc tach accuracy [Re: Edahlke] #1839949 06/02/15 07:44 PM 06/02/15 07:44 PM
Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada D DPelletier I Live Here
DPelletier I Live Here D Joined: Apr 2005 Posts: 15,134 Kelowna, B.C. Canada	Well to update; my Charger Specialties tach is apparently NFG. they used some sort of composite/graphite body when I bought mine and there are grounding issues. I bought the tach probably 8 years ago but the car has less than 20 miles on it...didn't last long! Sooooo, I can rip it out, take it apart and attempt to add proper ground wires.....or I can buy a new one somewhere and replace it......or I can give up and bolt a tach to the steering column like people used to do back in 1969. Dave 1970 Super Bee 440 Six Pack 1974 'Cuda 2008 Ram 3500 Diesel 2006 Ram 3500 Diesel 2004.5 Ram 2500 Diesel 2003 Ram 3500 Diesel 2006 Durango Limited [url] http://1970superbee.piczo.com [/url]

Re: Tic toc tach accuracy [Re: DPelletier] #1840182 06/03/15 12:21 AM 06/03/15 12:21 AM
Joined: Jan 2007 Posts: 7,664 IN A ahy master
ahy master A Joined: Jan 2007 Posts: 7,664 IN	I had my '70 Rally tach rebuilt and run it with MSD + the correct signal converter. It works in the sense it moves to the right as revs increase. Is it accurate? No +/- 300 RPM... mostly plus. I measure against the EFI computer that counts crank pulses and should be accurate. Think I'll add a tach on the column...

Re: Tic toc tach accuracy [Re: Edahlke] #1840198 06/03/15 12:51 AM 06/03/15 12:51 AM
Joined: Jul 2007 Posts: 11,836 Florida M mopar346 Let me tell ya about fat chicks!
mopar346 Let me tell ya about fat chicks! M Joined: Jul 2007 Posts: 11,836 Florida	Not to hijack but............is there a fix for the tach in my AAR readign roughly double the RPMS. I'm running and undercap conversion from Accel, essentially a Unilite module. Been running it for 7k+ miles now, no damage just double. Thanks in advance, Kevin Careful, your character's showing!

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