914-6 Weber Jetting Question
 

I have a 1970 914/6 which has the original 2.0 Stock Engine
It appears to be running rich ( high fuel consumption ~18mpg (european gallon)
It has 110 mains and 55 Idles
THe Haynes Weber book and elsewhere lists 105 Mains
SHould I switrch to these 105's??
THanks
Brian Doody

The mains are only used when the throttle gets more than about 1/3 of the way open, so the car actually runs on the idle jets most of the time.

I don't know what kind of jetting is recommended for 2.0 "T" motors, but I seem to recall Jim Pasha talking about going up a size in the venturis and possibly the idles as well to get more power out of the motor. Probably not that good for economy, though.

I'd think about going down on the idle jet size... But try the adjustments and such first!

--DD

When was the last time the carbs were cleaned and rebuilt? With the crappy gas we have in California the carbs tend to get goop much faster now than before so rebuilds are more necessary. How do the plugs look? Are they sooty or just nice and brown? If sooty then the engine could be too rich.

I think your best bet is to return to stock 914-6 jetting if your engine is basically stock and in good condition, and you live close to sea level (quite likely in Ireland ;) ).

If you need expert jetting advice or parts, Richard Parr at PMO here in California is one of the real Weber gurus left. He can provide any jets you might need, although I suspect you could source them locally or from Italy as well.

FWIW my car had too-large venturies and other carb issues when I bought it. Don't take anything for granted! Your car should have come with 27mm primaries/chokes.

Original Settings

Choke 27mm
Aux Vin 4.5
Main Jet 1.05
Idle Jet 0.50
Air Idle 1.45
Emulsion Tube F1
Air Corr 2.00
Acc Pump 0.50
Needle valve 1.75

Folks, Thanks
Yes the carbs are in good condition and clean, I completely rebuilt them last summer - Everything is running very well with the current jetting
nice smooth tickover and power delivery - But I cannot get more than about 18mpg + the exhaust is a bit sooty
Yes Im only about 50 feet above sea level on the West Coast Of Ireland
regards
Brian