Duster running rich

lenky1 said

Engine is 340 30 over. Zero decked. Kb pistons. 1.6 Harlan sharp rockers. Cam 292/508. No idea on install and timing as it was built 15 years ago by my uncle who is now deceased. Head have 202 160 valves. Holley electric fuel pump. Engine tuning is not my thing as I'm a body and paint guy. The information I'm giving is the from the stack of invoices he left in a folder. I really do appreciate the help. Thank you all

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You don’t have a carb problem. You have a timing problem. With that cam at a MINIMUM you need to be 10.5:1 and 11 would be better.

You are going to need in the mid to high 20’s for initial timing, maybe more depending on your actual, measured compression ratio.

My best guess is the timing is all wrong. On top of that, to get the engine to idle you have the throttle blades open way too far and you are idling on the T slots or worse.

You are a serious candidate for using manifold vacuum on your vacuum advance (assuming you have a vacuum can on your distributor) to get enough timing at idle. If you ask nicely, @Bewy can post up his standard package of information on how to do it. Read it because most likely you’ll need to do it.

The other thing is you will most likely need to drill small holes in the butterflies to allow more air to the engine without screwing the curb idle screw in so far you are idling on the T slots.

Any idea on what your compression ratio is?