Weber 38/38 DGV Jetting Thread.

[eurotrash]

So, after searching 16 pages deep in the GD, and using the search function to file older posts, it seems we need a 38/38 tuning thread similar to the Stance thread. This, for those coming after to find more easily.

If you have a 38/38, please contribute and post:

Motor specs. Compression Ratio, Cam, etc.

Your altitude.

Final jetting sizes. Main, Idle, etc.

Tuning tips

Lets build a good one here.

[doug73cs]

1976 2002 with 38/38 and Canon manifold. Not positive on the engine specs as nothing was provided by the PO but apparently stock rebuild with less than 10,000 miles on and a very good runner. Petronix and a mechanical dist are the only upgrades.

Altitude is 4000'

Idle 145

Main 145

Air 185

Idle should be tuned using Best Lean Idle outline explicitly and exactly as stated in http://www.redlineweber.com/html/Tech/38_dgas_tunning.htm and the trick is to get the jet that produces the least (preferably no) stumble when it transitions to the main jets around 2500rpm. You should be no more than 1 turn on the idle screw adjustment. All of your part throttle driving around town is done on the idle and the mains don't get involved unless your right foot tells them to.

Mains and Air are best set with a Air/Fuel ratio wideband sensor which means installing an oxygen sensor in the exhaust down pipe. In my simplistic experience the main jets are 2500 - 4500 and the air is for tweaking 4500 to redline. So set the main jets to give about 13.0 AF on the meter for the 2500 - 4500 range and the Air jets to maintain that 13.0 target to redline.

Of course, then you don't need the AF meter anymore but it is cool watching the numbers in the display. Because it's largely a set and forget proposition, a group of weber guys could share one meter and your permanent investment is just the sensor bung.

My 2 cents worth.

Doug