Speedo @ Tach drive gear ratio's?
Posted: Sun May 09, 2010 12:13 pm
by nortnlvr
I have a tach drive for my 69 Mark 3 when I turn the gear that connects to the cam unit twice it spins the cable end once. I assume that is a 2:1 gear ratio, there for a 2:1 tachometer would work? Is this correct? What are the gear ratios for the Speedometer and tachometer? Veglia? SMith? Trying to find an aftermarket tachometer for the time being, until I can fix my Veglia.
Re: Speedo @ Tach drive gear ratio's?
Posted: Sun May 09, 2010 1:23 pm
by DewCatTea-Bob
" I have a tach drive for my 69 Mark 3 when I turn the gear that connects to the cam unit twice it spins the cable end once. I assume that is a 2:1 gear ratio, there for a 2:1 tachometer would work? "
____ Since the camshaft turns at half-speed of the crankshaft, then a tach.dial is needed which should be preset to indicate 4-times as many revs as it's drive-cable spins.
" Trying to find an aftermarket tachometer for the time being, "
____ I recall that old Suzuki models are said to have a 4:1 ratio.
__ Let us know if you've found any other tach-dials with the correct ratio !
Hopeful-Cheers,
DCT-Bob