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larry8200

eBay tach not so hot.

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larry8200
I guess I dont know what a low idle is, what I thought to be 800-1000 was actually close to 1500. This is at warm no-load idle, and warm no-load full throttle. Digital dash tach is set to "Engine fires every other revolution". When set to "Engine fires every revolution" it reads from 600-3100 RPM. Test Tach is a Lab grade Calibrated, Certified MIL STD16049C spec. The BGB's 1:1 and the output shaft turns at engine speed. The new tach reads in 60 rpm increments (blah) so I'll give it the 1440 when the actual speed is 1491.9. 1500 would have been better... When the engine speed is actually 3148, no way I can accept (or believe) 5520. I haven't checked to see if the hour meter function is any more accurate than the tach yet.








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donmoore1904
quote:
Originally posted by larry8200
I guess I dont know what a low idle is, what I thought to be 800-1000 was actually close to 1500. The new tach reads in 60 rpm increments (blah) so I'll give it the 1440 when the actual speed is 1491.9. 1500 would have been better... When the engine speed is actually 3148, no way I can accept (or believe) 5520.
Larry, I think you are being too critical here. You just need to dial in a correction. Try this: RO = RI * .4059 + 907.4, where RI is the reading and RO is the actual speed. You just have to mount a calculator to the dash in addition to the tach. Cheers! Don ps I got my 7010 idle so low you wouldn't believe it. It is like tap tap tap tap tap. Sounds like it is just barely running, and nice and smooth. I never got the mixture perfect, I have to admit. When I accelerate from idle I get an occasional slight stumble.

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