409/425 Carbs help

Redmanf1

Member
I am looking for someone that can rebuild the original carbs for a 409/425. I had them rebuilt a few years back and they have never seemed right. The person that did them is no longer with us so I am not even going to mention any names. It seems as soon as the engine warms (190) up it does not run right. I have a DeWitt's direct fit aluminum radiator with factory clutch fan and shroud. I do not know it something in the carb is bad or what. I have taken the top off and checked the floats to see if they were to high. It acts like it is being flooded with gas but I can look down into the carb and no gas is dripping into the body. I was thinking about replacing the carbs want to keep my original air cleaner. I did not see any other carbs that is able to do that. So does anybody know of a reputable carb shop that can rebuild and liquid flow test the carbs before sending them back?

Thanks for any help
Nelson
 

pvs409

Well Known Member
Supporting Member 11
The best is to call them on timing especially now.
At least a month, last winter.
best I can remember for one AFB ( they did my 380 HP Carter AFB for $400.
it had a bad throttle shaft ( vacuum leak) and was running rich.
they were recommended by my well known local professional classic car restoration shop.
 

Blk61409

Well Known Member
Supporting Member 9
Larry Wells in Nebraska.
817-966-7866
Still use him, was here in Ft Worth and moved back to Nebraska.
 

Redmanf1

Member
I replaced the choke coil with an NOS one and it works great. I am just concerned if I have them rebuilt again I will have the same problem. It is strange as soon as they heat up it is like the gas will boil over and cause it to run ruff like it is trying to flood out. It does something like that when going down a hill or a hard turn. I have checked the float and even lowered it as far as I would care too. I just don't want to end up with the same problem. I am leaning towards new carbs any suggestions? Anything that will work with original air cleaner.
Had the engine rebuilt with forged pistons, SS high flow valves, balanced, Z11 cam, ect. It runs great as long as you are on the gas :) :)
Picture of car below.


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409.jpg
 

Redmanf1

Member
Running the pertronix in stock dist with matching coil. Also using stock base carb gasket. I have been thinking about using the Phenolic carb spacer but need to measure to see how thick of one that I can use.
 
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Jim Sullivan

Well Known Member
Supporting Member 10
Edelbrock makes a 3/8" thick insulator/gasket. I am running those on my dual quad set up. It's still cranks for a minutes after it sits while hot. But nothing unacceptable. It runs and idles great. Another possible problem could be the fuel your getting in your area.
 

Redmanf1

Member
Can you tell me what the Edelbrock part number is that you used?
Thanks

Edelbrock makes a 3/8" thick insulator/gasket. I am running those on my dual quad set up. It's still cranks for a minutes after it sits while hot. But nothing unacceptable. It runs and idles great. Another possible problem could be the fuel your getting in your area.
 

Jim Sullivan

Well Known Member
Supporting Member 10
I'm pretty sure the number is 9266. I am using Edelbrock carbs, so I'm not sure now, if the bolt pattern on the insulator will work with the stock AFBs.
 
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