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Discussion Starter #1
All the articles I see talk about the timing marks, but nothing says the actual advance in degrees.
Anybody know what they have set their ignition to in degrees? I'm especially interested in lightly modified engines running California 91 octane pump gas.
I seem to remember somebody saying they were running 34 degrees of advance on their modified 2 liter with pump gas.
I'm running 27 degrees (if I measured it right) and getting occasional pinging on steep hills / low rpm.
Soon I'm going to check the timing and the advance mechanism, springs etc. But I'm very curious what other people are running for ignition advance...?
Carl
 

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Discussion Starter #3
Thats a great centerline chart! But whats the / in the timing numbers mean? Like "27 /33"? I thought that might be indicating a range, like "27 to 33" but I'm not so sure...
C
 

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Yup, it's a range.
The 'Timing F' is the at idle range while the 'Maximum Advance M' is the range it should fall into when advanced at the given RPM. (not sooner mind you, but from that RPM upwards)
 

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Discussion Starter #5
Interesting how different all the two liter variants are. Ranges from 26 degrees all the way to 42!
So where are people with thier modified 2 liter engines? Anybody else as low as my 27 degrees or lower?
C
 

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Define 'modified', or at least what your modifications are.
There's a world of difference between a 2l that's just had a hot intake cam and header put to it vs a high compression, big valve, over bored, forced induction 2l.

I got 11mm cams, stock compression, free flow exhaust and programmable EFI feeding through ITBs and run right around 35-37 degrees on 89 octane.
 

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Here's info from Wes Ingram: Ideal timing should be approx: 5 degrees at 800, and about 36 to 37 degrees at 4000 rpm.

Interesting how different all the two liter variants are. Ranges from 26 degrees all the way to 42!
So where are people with thier modified 2 liter engines? Anybody else as low as my 27 degrees or lower?
C
 

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Discussion Starter #8
Marks

Ok, the marks on my 2 liter engine (origin unknown) are in this order:
F P M
Note the F mark (Fissa, static timing) is AFTER TDC on this pulley.
By measurement with my strobe, the P (Punto, TDC) is 27 degrees from the M (Massimo, full advance) marks.

This looks like the "1972-1975 2000 Spider,GTV, Berlina fuel injected for the USA" line on the Centerline chart.

Can anyone explain the variances in that chart for me? I'm really curious why the marks moved around relative to TDC...

(Waiting for the white paint to dry on the timing marks so I can see this stuff better when I try again)
C
 

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Vintage Veloce (do you have a name?) The retard dial timing lights are notoriously innacurate unless you bought a professional one, and they all are not really designed to operate at the 3000 plus rpm that it takes for the distributor to become fully advanced.

And you have not told us what year of engine you are working with so we could possible tell you what the M mark is BTDC on your pulley.

Use the BB search feature to find the several posts that describe how to find the optimum advance for YOUR engine combination.
 

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Discussion Starter #10
Hi George. Sorry old habit has me signing "C". I'm Carl.
I don't know the source/year of the 2 liter engine. Does an index by engine number exist?
My digital timing light is pretty good, but the pulley could have been changed on the engine as well. So who knows! Guess if I get serious I'll have to check TDC manually and check the pulley marks if I really want to know my degree setting. Maybe I'll buy a dial gauge.
At any rate I retarded the beast about 3 degrees and it seemed better on a short test drive. But the pinging was very intermittent, weather fuel and driver dependent. So I'll see over the next month or so.
Oh, and I did see your old thread, saying you can't hear Alfa's pinging anyway! Hah!
But your comment was interesting an max advance not necessarily being max performance. We will see next time I bump into a dyno test.... ;-)
Carl
Vintage Veloce
 

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Carl, although this method is not completely fool proof, you may be able to get an idea of your engine's origin and production year by comparing the engine number with Fusi's production numbers.
 

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If you post the engine number, or send it to me in a private message if you prefer, I may be able to get a bit closer than 'later than 1972'.
 

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Discussion Starter #14
Thanks to all, the centerline chart did give me a good basis to understand the baseline settings. Now my question is one of curiousity, as in why did some models have the fixed timing well after TDC and the others before TDC. And yes, I know its probably compression, fuel and cam timing related!
I'm guessing its related to USA emissions from the period, and that drove some cam timing changes that made the whole ignition curve to be retarded?
I'm surprised after my raising the compression and changing the cams that my engine still seems to be best with this retarded ignition curve. Either I'm just too hot rodded and need this retarded curve, or there is something else about the engine that sets those timing marks differently relative to TDC. I just can't imagine what that would be!
I should say the engine runs great and dyno's well. Peak of 115HP at 6200 RPM the rear wheels on a Dynojet, Max torque of 114 ft-lbs at 4000RPM. This is before I just retarded it about 3 degrees.
Carl
 
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