Tiny Tach Setup

I installed a tt on my new Suzuki 20 hp. Trying to figure out the correct setting from chart. In playing with it 720 was the only one where the readings seemed legit. Does anyone know?

Here are the options.

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No clue, but I had problems with one once, and their customer support was very quick and helpful.

suzuki wrote:

I installed a tt on my new Suzuki 20 hp. Trying to figure out the correct setting from chart. In playing with it 720 was the only one where the readings seemed legit. Does anyone know?

I guessing here,
the 20hp Suzuki is 4 stroke ?
if so one spark per two revolutions

Yes it is a 4 stroke 2 cylinder. Thanks a lot man! I got it to keep track of my break-in hours and to prop it correctly

I could be completely wrong but if its a two cylinder wouldn’t you want one spark per one revolution?

I’m thinking along the line of igotone. My memory of high school shop class was 4 stroke was 1 spark per 4 revolutions per cylinder x 2 cylinders equals 1 spark per 2 revolutions. Could have bad memory though.

CBMN wrote:

I’m thinking along the line of igotone. My memory of high school shop class was 4 stroke was 1 spark per 4 revolutions per cylinder x 2 cylinders equals 1 spark per 2 revolutions. Could have bad memory though.

Nope. Intake, compression,power and exhaust are the strokes that happen. In a 4 stroke engine those happens in 2 revolutions of the crank.

Go with the one that seems reasonable. Some setups have a “wasted spark” and fire every or every other revolution. https://forums.iboats.com/forum/engine-repair-and-maintenance/mercury-mariner-outboards/581325-silly-short-question-how-many-sparks