Hello Scotty and fellow wrench turners,
I recently inherited a 1966 Ford Mustang GT Convertible with a modified K-Code 271+ hp/289 Cubic inch V8 mated to a C4 Automatic from my grandfather following his passing. The car has under 100k miles and is a weekend cruiser and it's a 20/20 car (Looks good 20 feet away at 20mph...). The engine was modified by my grandfather and I do not know the specifics, but it has a non-stock intake, bigger cam, and set of headers in addition to a Holley carburetor that replaced the Autolite which should be there, my guess is it is a 600/650 cfm Holley. I'm at a loss identifying the exact carburetor CFM and was hoping for advice on it. There isn't a clear part number just a Ford remanufactured sticker and a date code from the early 1980s. I'm looking at simply purchasing a new Holley, with a manual choke and vacuum secondary's as I can't fathom using a stock Autolite carburetor. An Autolite 4100 for a K Code Automatic that "Should" be on it would nearly pay for a semester of my medical school and it's not a stock car anyway, even though it is a real K-code, dealer added GT package car. I am looking forward to enjoying it summer 2022 after the transmission is rebuild as the seals are leaking, as was the carburetor, the downfall of deferred maintenance and sitting for the past few years. I am hoping to be able to take my grandmother for rides and be able to go on weekend road trips of 500 or so miles and have vehicle that is as reliable as can be mechanically. I'd be happy to send pictures as I can't see how to add them here and would appreciate an identification of the Holley Carburetor if possible. I would also appreciate a mechanic's perspective on what it should be replaced by, as the current carburetor needs to be completely rebuilt with new gaskets, jets, and the choke is not in use at all. Many Thanks.
I used to have a '66 Fairlane with 289 V8 many years ago, though much tamer than yours. (The Fairlane shared the same basic Falcon platform as the Mustang.)
Here are suggestions right from the horse on identifying your Holley carb, there should be a list number:
https://www.holley.com/blog/post/how_to_identify_your_holley_or_demon_carburetor/
You could consider adding an electric choke kit. It's a little more convenient than a manual choke, though nothing wrong going manual either. Right now I have cars with both setups and both ways are working fine.
I also recomend an electric choke if it is in the budget.
As for identifying your carb, @ChuckTobias sent a good link for that information.
Electric choke kits are not expensive, I added one to my '71 Ambassador for about $30 earlier this year when I found the heat tube for the original choke had rusted out. I have a manual choke on my '67 Rambler convertible and that works well too, you just have to remember to operate it.
Thank you both for the link and perspective, much appreciated! Unfortunately there's no list number, so I'm now believing it was a Frankenstein-style assembly. I'm a sucker for operating a car, so I'll stick with the manual choke, and wish I had a manual transmission, but too many memories and family members that wouldn't know how to drive it to swap that out. Thanks again!