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Posted by: FlacaProductions May 5 2023, 04:06 PM

Just set/confirmed my 2.0 timing.
Vac hose from distributer removed and plugged/2800rpm/28 degrees.

It runs good, how do you how/how can you tell when it's "right" or optimal? That magic balance between power and efficiency.....

Posted by: brant May 5 2023, 04:13 PM

Stock cam
Follow the factory spec for sea level

Higher altitude (like Colorado)
You can advance another 1-2 degrees
But should not if the car is also driven at sea level

Posted by: yeahmag May 5 2023, 07:12 PM

Carbs, change in compression, cam change, type of fuel, etc... all make it a seductive dance of power. I started with 12 degrees BTDC at idle and 28 degrees BTDC above 3K RPM and went from there.

I'm not there now... Keep an eye on AFR and CHT and experiment. Going lean (having to add fuel) typically means you are headed in the right direction.

Posted by: bkrantz May 5 2023, 07:39 PM

Oh, I thought you meant for making a move on your date.

Posted by: FlacaProductions May 5 2023, 08:07 PM

QUOTE(bkrantz @ May 5 2023, 06:39 PM)

Posted by: ClayPerrine May 6 2023, 04:54 PM

While playing with the timing on a Megasquirt injected Type IV, we found that anything over the 28 degrees specified in the manual resulted in a loss of horsepower and torque.

Those German engineers seem to know what they are doing.

Posted by: emerygt350 May 6 2023, 06:54 PM

Interesting. Has anyone else found the same ( 28)? I have kind of suspected it but I do feel perhaps the curve moves a little.

Posted by: Dave_Darling May 6 2023, 11:00 PM

Two ways:

1- Follow the factory specs.
2- Put the car on a dyno and try different settings.

--DD

Posted by: emerygt350 May 7 2023, 04:35 AM

Yes, but wot pulls don't really cover real driving characteristics. On a stock 2.0 there is also idle characteristics as well as partial load response all in the mix.

Posted by: Dave_Darling May 7 2023, 08:11 PM

Yes, that would be part of the "try it on a dyno". The best would be ones where you can vary the load so you can test different load/RPM combinations.

--DD

Posted by: VaccaRabite May 8 2023, 05:38 AM

Without a dyno or a lot of instrumentation it really is best guess.

On a stock setup - set it at 28* and walk away. On anything else... Trial and error.

Back ages ago when I still had carbs, I tried advancing as high as 32 degrees - which idle LOVED but it pinged under load. Immediately backed it down to about 30 and the engine seemed to like that, but ran hotter then I liked. I eventually settled on about 29* for a season before pulling the carbs and starting the EFI journey.

Zach