Verifying Tachometer reading. FINAL REPORT

Boomyal

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Aug 16, 2003
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Are there any inexpensive tools to verify the rpm of an engine.(actually verifying tach reading) Maybe something like a laser aimed at the crank pulley or something that senses pulses.<br /><br />I know the local Vehicle inspection station just tosses some kind of doo-dad on your hood and your rpm displays on a monitor.
 

Boomyal

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Re: Verifying Tachometer reading. FINAL REPORT

Thanks QC. I just installed an MSD 6A ignition with an MSD Blaster 2 coil on my 5.0L. There is a lot of to do about tachs working or not using the built in tach lead. If the tach fails to function you are supposed to get a seperate tach adaptor.<br /><br />My tach works but I think it might be reading high. I need to verify it before I go very far.<br /><br />EDIT: One should never fail to check ebay for anything you are looking for. I keep reminding myself to keep it on the top of my search list but I often forget. They have bunches of them starting at $35.00.
 

QC

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Re: Verifying Tachometer reading. FINAL REPORT

Originally posted by Boomyal:<br />EDIT: One should never fail to check ebay for anything you are looking for. I keep reminding myself to keep it on the top of my search list but I often forget. They have bunches of them starting at $35.00.
Some will argue with me I am sure, but I believe that Ebay sets (or will set) pricing for everything on the planet. Shame on me for not looking there. I may just have to get me one . . .
 

f_inscreenname

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Re: Verifying Tachometer reading. FINAL REPORT

Get a $35.00 tach from Pep Boys or any other auto parts outlet. Then compare the readings from each.
 

Boomyal

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Re: Verifying Tachometer reading. FINAL REPORT

Originally posted by f_inscreenname:<br /> Get a $35.00 tach from Pep Boys or any other auto parts outlet. Then compare the readings from each.
If you mean a guage type tach f-i, it would be affected by the same ignition that my current tach may be affected by or it may not even work at all without an MSD tach adaptor. This is why I am looking for a tach that does not operate off the ignition system.
 

Ralph 123

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Re: Verifying Tachometer reading. FINAL REPORT

Boom, be sure to let us know how it works...
 

Boomyal

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Re: Verifying Tachometer reading. FINAL REPORT

Originally posted by Ralph:<br /> Boom, be sure to let us know how it works...
Uh Huh! I see! Well it won't be the first time I've been the Guinea Pig. :D <br /><br />Will do!
 

Dunaruna

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Re: Verifying Tachometer reading. FINAL REPORT

Just this morning, my tool rep called in and showed me one of those (it looks EXACTLY the same as the ebay pic). You place reflective tape on the harmonic balancer, the unit reads each revolution of the tape. Accuracy is within 1 (one) RPM, the unit will read up to 10,000 RPM.<br /><br />I can see it being very handy for outboard repairs etc.<br /><br />Care to take a guess at what price us Aussie suckers are asked to pay for that little toy?
 

whywhyzed

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Re: Verifying Tachometer reading. FINAL REPORT

they are handy.. try this when you get it:<br />aim it at a flourescent light.. It should read 7200<br />That's how they calibrate them.<br />60 HZ x 60 seconds x 2 ignitors in the lamp = 7200
 

Boomyal

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Re: Verifying Tachometer reading. FINAL REPORT

Originally posted by Dunaruna:<br /> Care to take a guess at what price us Aussie suckers are asked to pay for that little toy?
Ok Aldo. How about 150 Aussie Smackers. How'd I do, huh?<br /><br />EDIT: Try this one on for size Aldo. I don't know why it showed up on ebay US. They say they only ship to Australia.<br /><br /> http://cgi.ebay.com/NON-CONTACT-PRO...oryZ1504QQssPageNameZWDVWQQrdZ1QQcmdZViewItem <br /><br />I'll try that little trick Hystat. Thanks
 

Dunaruna

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Re: Verifying Tachometer reading. FINAL REPORT

That's a Sydney based company. Current bid $26.76. Down at the bottom of the page it says "will ship worldwide".<br /><br />My tool rep wanted $162.00. Me thinks he's dreamin'.<br /><br />Aldo
 

Boomyal

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Re: Verifying Tachometer reading. FINAL REPORT

Originally posted by Dunaruna:<br /> That's a Sydney based company. Current bid $26.76. Down at the bottom of the page it says "will ship worldwide".<br /><br />My tool rep wanted $162.00. Me thinks he's dreamin'.<br /><br />Aldo
If that is a good example how he's treating you on the rest of the stuff you buy from him, it might be time to find a new 'tool guy'! :eek:
 

deputydawg

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Re: Verifying Tachometer reading. FINAL REPORT

I used to have one that could not be wrong. It was the tach guage with a tube coming from the back. Inside this tube there was a shaft. At the other end of the shaft there was a rubber cone shaped peice. <br /><br />Place the rubber peice on the shaft into of against the center of the crankshaft. Usually wasy to find center by teh machining dimple, balancer bolt, or pulley. It would obviously measure the rotation of the shaft itself giving an accurate reading.
 

harrisg

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Re: Verifying Tachometer reading. FINAL REPORT

Boomyal... Please let us know how your laser tach works. I live up the road from you in Kalama and might take it off your hands when your through with it. That's of course if you want to get rid of it.
 

Boomyal

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Re: Verifying Tachometer reading. FINAL REPORT

Just received my laser tach. It was just as advertised.<br /><br /> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=ADME:B:EOIBSAA:US:11&Item=7545715159 <br /><br />I haven't tried it on my motor yet but I did aim it at a flourescent bulb, like hystat said to do and it measured 7197 rpm. I'd say, so far so good.<br /><br />However, my reasons for getting it may have just diminished as I called MSD regarding the high tach reading and they suggested that I take the tach lead off of the tach output terminal and hook it to the connection point of the MSD white wire and the Pertronix black wire. I did just that and now the tach shows 600 rpm at idle instead of 1000 rpm.<br /><br />It will still be fun to verify it. I will post when I have done that.
 

Peter J Fraser

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Jun 22, 2003
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Re: Verifying Tachometer reading. FINAL REPORT

Hi guys,<br />I've just been into my local engineers supply shop and they have the same photo tach with ABW / STANLEY branding on it for NZ$216.oo (US$150.oo).<br />Boomyal you're gonna need welders gloves to hold onto that so your fingers dont get burnt at that price.<br />I think the laser is a sighting aid to aim the tacho.<br />I paid over NZ$700.oo for the SHIMPO digital photo tach I bought about 15 years back.<br />But it is a good unit and has had a lot of use.<br />Mine also has 6 memories with recall for the highest and lowest speeds for each session.<br />You wont regret buying that at all.<br /><br />Regards<br />Peter
 
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