Carburetor recommendation

Lots of Ford 4100-A assemblies would bolt on. They will:

1. not have the same air fuel ratio curves under all conditions as a factory HP289 specific assembly. Ford created different balance tube orifice sizes and different economy valve channel jet sizes as part of the customization for each application. Some of the auxiliary venturi assemblies for HP289 applications are very hard to come up with. Main jets are cheap and readily available.

1. not have timing and opening rate of secondary throttle the same as a stock HP289 specific assembly unless somebody has already worked on the timing of events. Most 1.12 size units I have tested open the secondary way too soon and way too fast for even a hot rodded 289 c.i.d. engine. The timing can be changed but without some kind of test procedure each attempt would be a guess to go driving and test. A common complaint for any 289 c.i.d. engine with any 1.12 sized unit is the secondary working too soon and bogging the engine. That includes models that Ford installed some kind of flow control in that are now missing the part or parts, which is very common. I had one 1963 model with a pressed in 0.044” brass orifice, a small flow check ball, a copper-bronze compression spring, and a spring retainer pressed in. It was the slowest to open 1.12 sized unit I ever tested and Ford used them on two engines and one was a semi-production High Performance 260 engine. I had one and have seen one other.

Ford 4100-A models can be tuned, requires parts changes sometimes or requires part modifications sometimes, to work on just about any engine between 260 c.i.d. and 428 c.i.d. and Ford did just that. That is why there are many pages of carburetor assemblies for different engine and vehicle applications. I no idea who commercially does complete conversions of every functional detail to HP289 specifications. Henry in Portland Oregon might be someone to ask what he can or will do.

Quote from nadalin

Dan, thank you for the response.

You are welcome. If you do not know Henry's contact information,contact me through the message feature in this site if you want it. He has lots or cores and can do some custom work.