Author Topic: Cheap tach for tuning?  (Read 1269 times)

Offline Katfish

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Cheap tach for tuning?
« on: October 05, 2008 - 10:06:00 PM »
What kind of tachs do you use for tuning?  I'm going to try and tune my Edlebrock carb, thing has overly rich smell at idle.  Manual goes through a proceedure that requires a tach.  I'll only probably use the tach this 1 time, so I just want something cheap.

This is the only thing I've found so far.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95670

Any other suggestions?

Thx




Offline 422STROKER

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Re: Cheap tach for tuning?
« Reply #1 on: October 05, 2008 - 10:30:22 PM »
I use a Sears Engine Analyzer that I got a bunch of years ago.  It has a very low scale on it for fine tuning(0-1000rpm).  I would suggest a nice cheap Vacuum Guage to do fine tuning on a carb too.  I got a Guage for 10 bucks at the zone.  Has been invaluable with my engine tuning. :2cents:

Tom :2thumbs:
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Offline Aussie Challenger

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Re: Cheap tach for tuning?
« Reply #2 on: October 05, 2008 - 11:26:28 PM »
  Cheap tachs are not very accurate so don't rely on what rpm it might tell you, having said that you can still at least tell when the engine speed rises slightly as you adjust the idle.   :money:
  A vac. guage is probably a better investment, if your cam is radical place a restrictor in the tube connecting it to stop the needle fluctuating as much.   :2thumbs:
Dave

Offline RaptorF229

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Re: Cheap tach for tuning?
« Reply #3 on: October 06, 2008 - 12:23:48 AM »
actron has a auto multimeter that has a tach. I have used the thing for many other electrical stuff too.

Offline 71chally416

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Re: Cheap tach for tuning?
« Reply #4 on: October 06, 2008 - 12:41:47 AM »
A digital meter like that just counts pulses. It's much more accurate than an analog meter with a dial.  Stuff like that is dirt cheap anymore and the price doesn't detract from it's accuracy. For setting a steady state RPM like an idle speed it's fine. I would even use it to verify an analog tach's accuracy at different RPM's.  :2cents:   
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Offline Chryco Psycho

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Re: Cheap tach for tuning?
« Reply #5 on: October 06, 2008 - 01:04:24 AM »
If your cam has some Duration & overlap to it so it lopes even slightly at idle it will smell rich as the cylinder that do not fire are pushing raw fuel into the exhaust

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Offline Katfish

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Re: Cheap tach for tuning?
« Reply #6 on: October 06, 2008 - 06:46:39 PM »
Thanks for the replies.  My cam is not "loppy", probably not stock, but doesn't idle rough.  I guess I'll get the tach and give it a try.
The stinky rich exhaust smell is a major pain.  Plugs look good but it smells like raw fuel at idle.