Forum Opinion Please, Weber 44 or 40 on stock 2.0 Options

[Derek Seymour]

Currently have 44's that were just rebuilt, my experience is that 44's are a little big, and you need at least 2200 cc's of displacement to fully utilize the throatsize.

What's your experience/advice/opinion?

[GeorgeRud]

You need the velocity and vacuum for Weber’s to work correctly. If you think of it, a 2.0 liter 914 has the same displacement per cylinder as a 911SC, so most of the tuning should be similar. Red Paul Abbot’s excellent explanation on weber carbs at his Performance Oriented site. It should be required reading before anyone takes on playing with carbs.

BTW, if you’re using a stock cam, the original fuel injection system will probably run better than the carbs (though it doesn’t sound as nice).

[Gatornapper]

GR -

Rebuilding my 44's now, the venturi's are 45's......have yet to start the engine but it was running perfectly when parked in my friend's barn 10 years ago. Local Porsche dealer here put the 44's on.

The PO, who used to race 911's, said the 44's didn't produce any more power than the FI BUT made the engine far more responsive......change was made because dealer could not find ECU for the '76 - or so dealer said - dealer here does NOT have a good reputation.

SO, I guess I need to get the smaller venturi's ASAP.....I ordered the Weber Tech Manual last week and should get it this week.......

Thanks!

GN

You need the velocity and vacuum for Weber’s to work correctly. If you think of it, a 2.0 liter 914 has the same displacement per cylinder as a 911SC, so most of the tuning should be similar. Red Paul Abbot’s excellent explanation on weber carbs at his Performance Oriented site. It should be required reading before anyone takes on playing with carbs.

BTW, if you’re using a stock cam, the original fuel injection system will probably run better than the carbs (though it doesn’t sound as nice).

[porschetub]

GR -

Rebuilding my 44's now, the venturi's are 45's......have yet to start the engine but it was running perfectly when parked in my friend's barn 10 years ago. Local Porsche dealer here put the 44's on.

The PO, who used to race 911's, said the 44's didn't produce any more power than the FI BUT made the engine far more responsive......change was made because dealer could not find ECU for the '76 - or so dealer said - dealer here does NOT have a good reputation.

SO, I guess I need to get the smaller venturi's ASAP.....I ordered the Weber Tech Manual last week and should get it this week.......

Thanks!

GN

You need the velocity and vacuum for Weber’s to work correctly. If you think of it, a 2.0 liter 914 has the same displacement per cylinder as a 911SC, so most of the tuning should be similar. Red Paul Abbot’s excellent explanation on weber carbs at his Performance Oriented site. It should be required reading before anyone takes on playing with carbs.

BTW, if you’re using a stock cam, the original fuel injection system will probably run better than the carbs (though it doesn’t sound as nice).

You won't have 45mm venturies trust me on that ...