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Greetings,

I'm a collector of Jaguar E-Types and this is my first Alfa. I recently purchased a 1973 GTV with dual Webers. It's a nice, driver condition car and runs pretty well overall. The problem is that the car seems to run out of breath above 3500 rpm. I've been in other GTV's and they all pulled much better in the higher revs than mine.

Appears to have a stock type exhaust except for stinger rear pipe. Another item worth mentioning is that I end up with a black puddle under the exhaust while warming up.

Any suggestions of where to start would be much appreciated. I can solve most E-Type issues in my sleep, but this is all new to me. On a side note; I can't believe that it took me so long to buy an Alfa and I am looking forward to driving and learning about these fantastic cars.
 

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I can't tell you exactly what is wrong. But I doubt it has anything to do with your stinger exhaust, or the pool of black condensation that comes out of the tail pipe.

Most likely the Webers aren't jetted properly. How much do you know about Webers? They are more complicated than SU's but more flexible as well. Either take the car to a Weber guru, or pull the jets, record their part numbers, post the list here on the BB, and get peoples' comments.

Another possibility might be that the ignition isn't advancing. You can use a a simple timing light to verify that it gets to the "M" mark at high rpms.
 

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I think I would take a timing light to this engine before messing with the Webers.
Gutless above 3500ish indicates a stuck ignition advance mechanism.
 

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If it were me, I'd take a systematic approach to making sure the engine is tuned properly from A-Z.

As Jay notes, make sure the carbs are set up for your motor. You have a 1973 car that originally came with fuel injection, right? Here's a link to a lot of good Weber tuning info, including a simple DOS-based calculator to determine choke size and jetting: Alfa 105 Technical Info Remember DOS? The calculator still works with Win 7 and has proven to be an excellent starting point for Weber tuning.

After making sure the carbs are jetted properly, the rubber carb mounts are not cracked, loose or otherwise leaking air, and the linkage is opening the chokes all the way (It probably has after-market linkage), I'd use George Willet's very clear guide to synchronizing the two carbs by looking through the inspection covers. If you can't find George's instructions on the BB, write me at [email protected] and I'll send a copy.

Then I'd pull off the cam cover and check the cam timing, the adjustment of the timing chain (just because the cover is off) and look for unusual wear in the valve train (also just because the cover is off). I'd also check valve gaps, but that can probably wait unless the motor was unusually noisy.

Next, I'd check the ignition system, from distributor to plugs -- cap, rotor, plug and coil wires, plug condition and gap, ignition timing (for a carbureted 2L - not the same as FI or other engine sizes), ignition advance, etc. If the car has a front pulley from a fuel injected car, the marks are not appropriate for timing a Weber-carbureted car. You may need to make a new mark in the pulley to time at maximum advance, which should occur at about 4500-5,000 rpm.

Also, because Webers are sensitive to fuel pressure, I'd make sure the fuel pump provides 2-4 pounds of fuel pressure to the carbs. Some electric fuel pumps are set in the right range, some are not.

After you've done all that, if the car still isn't pulling like it should, it might be time to find a local specialist. Putting where you live on your heading will allow BB members steer you to the best help in your area.
 

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One ALWAYS starts a carb tune by checking the ignition -point condition, dwell angle, then timing- use a dial back to zero timing light. If any other ignition faults appear (Plugs, HT leads etc etc) attend to them first before you even touch the carburettors. If converted from Spica then you need to verify the carbs you have fitted are specced right. I also check float levels and verification the float needle and valve are working as they should before actually touching carb settings.
 
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