Question on Dual Carb setup

5

53vicki

Junior Member
My Dad has a 53 Ford with a 239 flathead. He's running two 2 barrel carbs (Ford 8BA) on a freshly rebuilt stock engine.

I've read that running 2 carbs (Ford or Holley 94) can cause issues on these engines partly due to the vacuum advance. Also have read some people plug a power valve on 1 of the carbs in a multi-carb setup to help it run better. I'm told the Stromberg 97 carbs are the best to use on a Flathead with multiple carbs due to them having mechanical advance.

Where is the power valve and if we block one does it matter if it's the carb toward the front of the engine or the one closer to the firewall ?

Any other suggestions ? My Dad just got the car back after it was in a paint shop for 2 years. He tells me the car is having trouble accelerating.

Thanks
 
I'd switch to a converted SBC dist beforw he ruins the engine, maybe pill the carbs and use an stock intake until the engine is broken in.
 
You will likely get a "mixture" of responses to the questions.

I don't like the concept of plugging any power valves except for use with a competition engine. However, the PV should be changed to a lower number such as a 3.5 The PV is located in the bottom of the float bowl(main) carb housing. The carbs will have to be removed from the manifold and the throttle base removed to see the PV.

Neither Stromberg or Holley carbs have any ignition advance system in them. But the 8BA carb you have is designed to work with the stock 8BA distributor advance system. You can try to make it work by plugging the port on one carb and attaching a vacuum line to the other carb and to the distributor pancake vacuum housing. This is better than nothing but will not be as good as using a centrifugal advance distributor as mentioned by O'Ron. I am assuming here that the carb linkage is set to directly connect the 2 carbs together and not some kind of progressive linkage??

I do like the idea of using a stock, single carb for engine break-in especially for those who are unfamiliar with multi-carb setups. Many 2 carb intakes can be used with one carb. but you would need to provide more information or do a runner exam to determine the feasibility.

If the car has been sitting for 2 years have the carbs also been sitting on that engine? It is entirely possible the carbs are gunked horribly.
 
Thanks for the replies. To answer a few questions;

It's an Offenhauser 2 x 2 intake on the car now.

The stock distributor has been replaced with another. I'll look at it today and let ya know what kind it is.

The car was started & moved around periodically over the 2 years at the paint shop. Stabil & Seafoam were put into the tank. The carbs are directly connected now rather than progressive linkage.

Thanks again for help/suggestions.
 
Looked at the distributor and it looks to be the original one to the engine.

Tag has "FoMoCo" script, 8BA and part no. 12127

I thought we'd installed another one after having the engine rebuilt prior to the car going to the paint shop 2+ years ago but I'm wrong.

Ron you mentioned using a converted SBC distributor. Please let me know exactly which distributor we should get with a part number. Whats involved with converting it for use on this flathead ?

thanks again-
 
Contact Charlie,ny on the dist issue. He also would have the low# power valves.I have a few left 4.5's and my normal ones 5.5. Talk to Charlie as we differ on leaving PV's out of them or even one. ken ct.I know hes jammed with work as i am and hes leaving tomorrow for the Canfield.ohio i talked to him today. ken ct.Most if not all kits contain PV's of #7.5 they open too quick for a 2x2 and just flood the engine with raw gas it cant use. ken ct.
 
53,
At one time I resisted using PV's on duals because what was available was not
reliable as far as I was concerned.
I now install PV's quite happily and with good results, high quality US made,
correct in/hg that open and close reliably.
Check your email you have my response to the email you sent me.
Gracias,
Charlie ny
 
Charlie ny said:
53,
At one time I resisted using PV's on duals because what was available was not
reliable as far as I was concerned.
I now install PV's quite happily and with good results, high quality US made,
correct in/hg that open and close reliably.
Check your email you have my response to the email you sent me.
Gracias,
Charlie ny
Click to expand...
Thanks for jumping in here.Have a safe trip to canfield. See you at Hershey. ken ct.
 
53 and Ken,
I would be remiss not to mention Jim Lindner aka Bubba......I sell a lot of
sbc/8ba dists each year, Jim sells 10 times that. It is a great unit and easily spins
a Flathead to 5 grand plus with no float. Yep single set of points, 6v or 12v and
infinately tunable without removing it from the motor...what is not to love....except
the ugly cap. Can no can your choice.
We leave for Canfield in the AM....time to hook up with the PA, Ohio and
W. Va boys.
Charlie ny
 
Glad I ran across this thread. We have dual Stromberg 97 carbs on a Fenton intake manifold. We also have standard, not progressive, linkage. It seems to be running rich.

Questions:
1. Is this an ok 2 carb setup?
2. On the aft carburetor, the spring for the accelerator pump lever is not in play. It is either broken or has been cut off. Should it be in place?
3. I have a replacement spring but I'll be darn is I can figure out how to install. (I have tried looking at the spring on the "lead" carb but not much help. I know that one end of the spring goes into the carb body and the other attaches to the lever, but can't figure out how. I'm assuming that the spring is meant to raise/lift up the accel. lever, that the "straighter" end of the spring goes into the carb and the "looped" end goes under the lever. But I can't make that work. Help!!
4. When driving and coming to a stop sign, the engine revs too much. I have to pump the gas pedal to get the rpms to go down. I have lubricated silicone) all of the linkage, to no avail. What is the remedy?
5. Will anyof these fixes address our running rich condition?

Thanks in advance...
 
I dont know why you cant figure out how it goes on.Look at the other one. The "L" shaped end goes in the slot just below the top of the clamping area for the air cleaner.// the other end "U" shaped goes over the fulcrum arm upside down. You do this end while installing the arm and shoulder screw all at the same time. Easy as pie. Can be done in approx.3 seconds. LOL ken ct. Bring the carb to Hershey,i'll install it for you,andyou can see how it goes on. Second thought dont even bring it i will show you how on 1 of mine. ken ct. GDF-4-6 In front of the Giant Center.
 
ken ct said:
I dont know why you cant figure out how it goes on.Look at the other one. The "L" shaped end goes in the slot just below the top of the clamping area for the air cleaner.// the other end "U" shaped goes over the fulcrum arm upside down. You do this end while installing the arm and shoulder screw all at the same time. Easy as pie. Can be done in approx.3 seconds. LOL ken ct. Bring the carb to Hershey,i'll install it for you,andyou can see how it goes on. Second thought dont even bring it i will show you how on 1 of mine. ken ct. GDF-4-6 In front of the Giant Center.
Click to expand...


Ken, What a dummy I am!!! I was trying to connect the spring on the plunger-side of the pump lever. Of course, it should go on the other side of the fulcrum. My bad. Thanks for the help.

Any comments on my other questions?

Thanks, Joe
 
Tough job trying to fix a ignition issue and a fuel problem at the same time. However thats how most end up doing it...
The dual carbs and the adjustment is a issue and there is a specific fix for the balance , jetting and adjustments on the dual carbs. Study the internet and hang out with some of the forums as to the exact procedures used to get this balance correct.

The ignition side of the coin is pretty simple , if you are trying to run a vacuum controlled distributor you need to switch to a full mechanical advance based on loss of a useable vacuum signal.
This can be done a number of ways, using either a Mallory or converted chevrolet that uses full mechanical advance units.
We do the chevrolet conversions as well as machine the mallorys to fit the flathead engine.
Be glad to help in any way possible.
 
Sounds like you may have an alimement problem with the linkage.Loosen one or both carbs from the manifold and twist them one way or another it may be a binding in the linkage. In other words not straight in line with each other. What kind of linkage do you have on the drivers side or pass side?? Drivers side is much better setup. ken ct.
 
ken ct said:
Sounds like you may have an alimement problem with the linkage.Loosen one or both carbs from the manifold and twist them one way or another it may be a binding in the linkage. In other words not straight in line with each other. What kind of linkage do you have on the drivers side or pass side?? Drivers side is much better setup. ken ct.
Click to expand...

Hi Ken,

Have pass side linkage. Will check to see if binding anywhere.

Would either of these (linkage and missing accel lever spring) be the cause of running rich?

Thanks, Joe
 
Drivers side is much simpler, 2 arms clamp to shafts and a straight pc of rod to connect together. Original throttle rod from firewall to rear carb and your done. OMO ken ct. Usually i recomend .043 jets and #67 or #68 power valves in them. ken ct. The drivers side linkage cannot be used on 8BA carbs or later ones with out changing to extended shafts.
 
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