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But Mad North-Northwest
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Discussion Starter #1 (Edited)
Anyone know stock cam timing for a 2L carb'd engine out of an Alfetta? This is what I have currently in my 1974 GTV. All the tables I've found only have US fuel injected timing for the 2L.

Doing some estimating in the car it looks to be 102/104, which would appear to match the +1/-1 timing from the earlier 1750 cars listed in TSB 77.03.01 Does that sound reasonable, and does anyone have documentation?
 

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Premium Member
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AFAIK all Alfetta's sold in the US were SPICA. Do you think that you have a converted US motor or a European one? The front timing cover will tell you which one it is. If it is US then the timing marks will be the same as for a Spider of the same year. I can give you the timing for any of them.
 

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Richard Jemison
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7,394 Posts
It`s cam dependent. What cams are in the motor? (casting #s) and what are the LC positions on your front cam caps? If the cams are 10548-01 the spider`s LCs were 99.5 / 99.5 which is far to small a LSA for any Alfa engine. Likely the 102/104 would be better with these cams, but drivability (torque) will be better at 104/104.

There was a TSB suggesting 104/104 back in "the day" for all the pre VVT cams.
 

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But Mad North-Northwest
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Discussion Starter #4
It's actually a European Alfetta motor. Per Alfa it was originally sold in Belgium as a US-spec GTV, and at some point it appears to have gotten a carb'd Alfetta engine (mechanical fuel pump and all.) I've got the US specs for cam timing but can't find the Euro Alfetta data.

It's actually an odd mix of US and Euro parts which has made sorting things out challenging sometimes. It's got Euro front turn signals and doesn't have the US rear license plate light assembly, but it's got mounting points/wiring for the SPICA electric fuel pump and vapor system. It's even got remnants of the 1974-only US seat belt interlock system. No idea on the full history.

Cams are currently the 10548-01 but those are recent, they are timed to the marks. Cap marks are definitely not 99.5/99.5, per my measurement they look more like 102/104, but tell me what you think.

I estimated by taking a photo down the cam, leveling the photo using the base of the cam cap as a reference, and then scaling & leveling the image of the Centerline scale. Did this a few times and I'm getting consistent results. It runs well so I'm not really inclined to take the cams out to measure properly, I'd just like to know where the marks should be per Alfa documentation.

1620652


1620653
 

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Premium Member
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According to the Shankle book all Euro 2L motors had 105480320001 cams timed at 99.5/99.5. I agree that yours look like 102/105. 3 degrees shift is unlikely to produce a seat of the pants change in performance, maybe 2 or 3 HP if my dyno testing is any guide.
 

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But Mad North-Northwest
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Discussion Starter #6
Mongo dunno. It definitely ain't 99.5/99.5, and it hasn't been re-scribed. Maybe it's an engine from an 80s Alfetta or something...didn't Alfa give up on the 99.5 timing at some point?

When I got it, if memory serves it had L-jet Nord cams, but the intake had been reground. So that wasn't much help.

Anyway, it runs really good, I was mostly just curious.
 

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The early Euro 1750's had timing marks at 102/102 for the 105020320001 cams. They switched to 99.5/99.5 with the 10548 camshaft that went into late Euro 1750's and all 2000's. Only the US got Bosch L-jet on NORD motors. ROW stayed with carbs until Motronic. The Shankle book was printed in 1986 and there is no mention of alternative cam timing for Euro 2L motors. It is of course possible that there was a change that Shankle did not pick up on.
 
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