repoman

Jetting for Weber 38DGES

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Hello all....

Long time 02 owner, first time poster.

I am just wandering if the Weber downdraft database ever got created ('02 FAQs).

I have a 74 02 with the stock cam and tii exhaust and would like to add the 38/38. If anyone has some experience with this setup, I would appreciate it.

Or if you have the 38/38, what jetting/cam/exhaust are you running?

If I need to swap cams or exhaust to better suit the 38/38, I can do that as well. Just looking for a good daily driver with some performance, and who knows, maybe some future track days....

TIA

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Stock cam, Tii exhaust, Cannon intake and rebuilt long block at 4000' above sea level.

50 idle

150 main

185 air

Average Air/Fuel throughout of 13.5 (+/-) though it's bit richer to 2500rpm.

I find the DGES like to be rich to run smooth. With some tweaking of the air and main jets can give decent mpg on the highway (4000rpm). You could hot up the cam to improve the top end as there is lots of umph in the bottom but you'll lose some to gain the other.

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Average Air/Fuel throughout of 13.5 (+/-) though it's bit richer to 2500rpm.

What are you using to measure the A/F Mixture? I have a A/F meter for my E23 & E28, however, it utilizes the 02 sensor

FYI...I am at about sea level and plan on "hogging out" my existing intake manifold.

Thanks again

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Western Motorsport wideband A/F Meter with an o2 sensor on the down tube just below the exhaust manifold. Lot's of other choices out there - just happened to be what was available locally. Helps judge how much to change the jet sizes (given what a pain it is on the DGES) but I still look at the plugs to confirm after I think it's dialed. Very light tan.

WMS unit gone. Here's another alternative http://www.sdsefi.com/mmm.htm

The Cannon intake comes hogged.

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Yeah they like to run rich. I dialed mine back to a 700 idle and have to give it a little to turn her over but once going it runs very smooth.

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