Tach accuracy
10-04-2006, 10:37 AM
#1
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Tach accuracy I was browsing through the MadZ28.com and i noticed that he said near desired rev limited:
(Keep in mind that the stock tach may show 300-400 RPM more than actual RPM!)
Is this true?
(Keep in mind that the stock tach may show 300-400 RPM more than actual RPM!)
Is this true?
10-04-2006, 11:34 AM
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knowing in gm that tach accuracy thing is probably intentional because obviously the pcm has to know the exact rpm to operate correctly but the guage doesn't necessarily have to show it
maybe a little error on the safe side for engine reliability especially when i dont even hit the stock rev limiter in my car (5886rpm) until the tach reads about 6100 but in 1st gear you hit it right about 5800 because im sure the tach cant keep up
the inaccuracy of the tach seems kind of intentional to me
maybe a little error on the safe side for engine reliability especially when i dont even hit the stock rev limiter in my car (5886rpm) until the tach reads about 6100 but in 1st gear you hit it right about 5800 because im sure the tach cant keep up
the inaccuracy of the tach seems kind of intentional to me
10-04-2006, 01:34 PM
#5
It's true. The higher you go the further it's off. Evidently the error is percent, not RPM. Most look about 100 high at idle, but when mine was stock I shifted it at 6000, the tach showed almost 6500. I now shift it at 7K, the tach lays on the peg for some time before the shift happens. I shift a local customer's car at 6600, it also pegs the tach.
