13B timing question
Why? Emissions, combustion chamber shape (compression dish), spark plug location etc.
You can do a 10 degree split. I tend to do that on my stuff. Or try 15 degrees. Whatever works best for you.
You can do a 10 degree split. I tend to do that on my stuff. Or try 15 degrees. Whatever works best for you.
Joined: Mar 2001
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Jeff is correct, as emissions standards change, timing does as well.
i tested an FC, and with timing +10, nox was higher, but HC and co were the same. the cat may mask a change in HC or CO. a healthy rotary with a cat will have HC's in the 20's, and without the cat it will be around 1900.... removing the airpump adds another 1000
anyways, at idle you want timing to be -5 BTDC L or at TDC, up to you, what ever the engine likes. at WOT you're also looking for what the engine wants, somewhere between 18BTDC L and about 26BTDC L.
once you're in the sweet spot (^^^) more timing isn't going to make much more power
i tested an FC, and with timing +10, nox was higher, but HC and co were the same. the cat may mask a change in HC or CO. a healthy rotary with a cat will have HC's in the 20's, and without the cat it will be around 1900.... removing the airpump adds another 1000
anyways, at idle you want timing to be -5 BTDC L or at TDC, up to you, what ever the engine likes. at WOT you're also looking for what the engine wants, somewhere between 18BTDC L and about 26BTDC L.
once you're in the sweet spot (^^^) more timing isn't going to make much more power
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