Running WAY too rich.

So I just did a leakdown on my 79 Mustang 17 (302 V4) and it came back that all of my cylinders are between 60-70% @ 100psi with 30-40% basically just getting past the rings. When I took my plugs out they were blacker than the night sky, so obviously I have an over-fueling issue. I was wondering if somebody could tell me if this is the correct carb for my boat, then we'll go from there.

Holley 4bbl

When was your carb last re-built? Call Vince at www.skidim.com and he can get you the proper carb re-build kit. In your top picture you captured the the carb numbers stamped on the air horn. Before replacing the carb, I would try this option.

JQ

Duane in Indy wrote: Per the Holley manual: List 7159 is a model #4160 450cfm rebuild kit #703-33 Google "d4jl f"   several sites show that carb for a 302

Just to add a little to what Duane said 302's came with a 450 CFM Holley and my Holley manual agrees with his.

Also if you rebuild it, do yourself a favor and get some new bowl screws for the front float bowl cause those style are just terrible for a lack of any better words. You'll see why when you take them out

The secondary bowl screws look like they've been replaced (they appear to be a hex head) but the front look original

The front are longer than the rear so make sure you get the right ones.

And 450 CFM is plenty for a stock 302