Congrats on buying old number 84

The place to start with jets is by ID'ing the venturis. Jets are sized to the venturi. You want the proper air/fuel ratio for a gasoline engine, which on a DCOE is 4 times the venturi size. So for 32 mm venturis, fit 128 jets. Next, the air jets are related to the jet size, so go with air jets = main jet + 50. See Weber DCOE carburetor for more tuning information.

All gasoline engines want the same air/fuel ratio, but you will need to fine-tune it if you want power without wasting fuel. Tune it for 14:1 cruising with 12:1 full throttle (via power valve). You could go leaner on the jetting (14.7 is frequently used to average out emissions or even leaner 16:1 for max fuel economy) but it won't run as smooth.

And then tune it for quirks of the engine such as high overlap camshaft and accelaration characteristics which are best served by air jet correction and accelerator pump selection.

Hello all,
I recently purchased a race only 72 1200 with dual dcoe 40's. Previous owner got into and found out he didnt really know anything about how to get it running right.

So I pulled all the jets and found a totally random assortment. 4 different idle jets, mains, etc. No wonder it barely runs at idle and through the mid range. On the top end it hauls ass though. I havent measured the chokes yet.

So i found this thread: http://datsun1200.com/modules/newbb/viewtopic.php?topic_id=6945

I have 2 other cars with dual dcoe's so I have some experience in getting them working, but between all my cars i dont have the jets listed in that thread. The motor is race built a12, unknown cam, but cosworth pistons, high compression, header, and a good oil system with a boxed oil pan, oil tank, etc. The motor revs up to 7500 with no issues or noises. I dont even want to start trying to tune it until I buy matching sets of jets. So I just want to check with anyone thats running a dcoe setup to see if the b210 jets in that thread would be a good place to start? Buying jets is no issue I just dont want to start too far off.

Economy is no issue as this car is race only. Road tracks, mainly sonoma.

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