What would be the best replacement carb for my stock 401. There is the stock Rochester on it now and I do not like it at all. I do not plan on doing anything internally to the motor to enhance power but I think if the carb that is on it now were a horse it would have been shot a long time ago. I am a new owner of the nailhead so any advice would be grealy appreciated. Thanks
Prats63, I have heard that the Edelbrock AFB replacement works well on the Nailhead in the 750 or 800 CFM version, but I am not sure if it would hook up to your throttle linkage. I recall that the Dynaflow equipped cars had two rods on the throttle linkage. The rod on the top rotates backward with the pedal, and the one on the bottom rotates forward. They can bind in the wide open position if not positioned correctly. This happened to me using a Holley 750 with an adapter plate on a 63 Nailhead. I jiggled the throttle, but to no avail. I had to turn the key off and coast to a stop. It was a very scary moment as I was already moving along pretty well when I hit it. I was able to adjust the linkage better, but it would still stick a little occasionally. Cheryl :eek2:
Help with this.... Has anyone here ever connected a Edelbrock 1411/electric choke to a 63 401. I'm in the processes but have heard mixed answers on how to hook up correctly with the Dynaflow. If needed I'll find a nos carter carb (600 - 750)?? and just use it. My rochester carb leaks everywhere and I don't want to rebuild it. Any insights or sugestions would be great!!! Tom
I would recommend you find a Carter AFB for a Buick, '61? to '63. It's a direct replacement for your Rochester. The throttle linkage is correct for the Dynaflow, your air cleaner will fit and you can put an electric choke (aftermarket) on them. They are easier to work on too! Just my .02, hope it helps, Frank P. :beer
Tom, The Nailhead Carter AFBs only flowed in the 500 CFM range. There is more information concerning that in this thread. The small cfm significantly increases the velocity of the fuel at a lower rpm. This improves low-end performance, but at the cost of reaching the carburetor's maximum flow capacity at a lower rpm, and reducing the maximum rpm. That is why it will go like stink up to 50 mph as Russ suggested on the Nailhead site. If you want your Nailhead to spin to at least 5500 rpm it will need at least 650 cfm using the following formula: The intake valve opens every other engine revolution. This means the engine requires 1/2 of its total displacement in any given revolution to fill with air. Multiply 1/2 of the CID times the maximum rpm to get the maximum cubic inch flow needed per minute. Divide that number by 1728 (cubic inch per foot) to get the maximum cubic feet per minute (CFM) needed for your engine. Small intake and head volumes increases the velocity of the air through them and produce a pseudo-supercharging effect. This will produce a need for even greater CFM then the calculated value. The nailhead has very small intake runners. That explains why the calculated value for the 401 at 5500 rpm would be 650 cfm, but it may benefit even more from a 750 or 800 CFM carburetor. If you can not get the hard linkages to work without binding or producing the right ratios between them, I liked the suggestion Russ had about using a chain in his answer on the Nailhead site. I think you will be happy with a 750 CFM carburetor when it is all said and done. I really liked the 750 Holley on my 63 Nailhead, and it was a huge improvement over the original Rodchester. Keep at it! - Cheryl
I've got a 63 wildcat that's being parted. 401 4V I'll check the carb numbers in a day or too. Work is keeping me really busy.
I am also looking for a decent driver side tail light assembly for a '63 Wildcat as well as a few odds and ends.
Yep it's a carter AFB. Here's all of the numbers I could find on it. I have no idea what any of them are. Passenger side of carb 2 6 1585 Drivers side of carb 0 - |72| Choke plate 7-235 If I remeber correctly the drivers side light assembly has been hit. I'll check into it the next time I go over. Let me know what else your looking for and I'll get some pictures. The car is 4 door BTW. You can seen a couple pictures of it in the cars for sale section, I'll bring it to the top again.
Mike, Did you ever get a chance to pull that carburetor? I'm still looking.... Hope to hear from you, Taylor
