Cobra Carter dual quad question

[shelbydoug]

The 3300/3301's are for my 428. They needed setting up so I just ran them in on the 347. Not exact but close enough to break the new 428 in with.

My 1850's are -1s from 67 or 68. They're ok and simple enough. I can get them to idle down to 700+ or so and that's with a 236@.050 cam, so that isn't bad.

I had to go with an electric choke on them. The stock hot air Holley was being somewhat erratic.


I have a pair of matching '60s 1848's but haven't gone through them yet and probably won't bother with them at this point.


No. I don't like the 4118's. It may just be that I don't care for single 4's with vacuum secondaries? Dual 4's have my attention.

The C6OA apparently was set up with 1850's 652's on the T/A cars and there was an issue under race conditions of the secondaries not wanting to shut.

That's where those new concept "mechanical secondary" carbs Randy has stemmed from. "Necessity is the mother of invention" thing.


One of the Ford mags did a dyno of duals v single 4's and thought that they proved it was a 15hp difference. The issue was that they had an RV cam in their dyno engine which really doesn't show the possibilities. It might have been with an Edelbrock 2x4 so I'm not sure that equates either?

I'm sure that the difference on mine is much more then 15. Maybe closer to 100? The difficulty in that is the cam selection becomes really critical and even the headers are joining in with the party.


I've run the 69 Boss 302 3310, the 68 428 Holley, and a 3259 (S2MS) with all the same disappointment.

The Holley double pumpers are good. A 4776 was a little small and a 4779 about right but maybe a little large for sudden WOT?


No matter now. My 68 GT350 is the dual 1850's on the C6OA. The 67 GT500 is the 3300/3301 on the C7ZX and my Pantera is 48ida's on a high port Hall Weber manifold.

I don't foresee any more experimentation in my future with the possibility of  substituting two S8MS-9510-C center sections for the 1850's but dual 600 double pumpers, that I could talk myself into trying? Unfortunately that series of carbs can't even be altered to fit a 2x4 intake. There are no side hung bowls available for that kind of a set up.


Then again, I was always my own worst enemy and why should that change now? What else do I have to do but throw fouled spark plugs at a Motorcraft sign on the wall?

[TA Coupe]

A good article concerning 2x4 setups.

https://www.motortrend.com/how-to/5-tips-dual-quad-carburetion-success/

          Roy

[shelbydoug]

A good article concerning 2x4 setups.

https://www.motortrend.com/how-to/5-tips-dual-quad-carburetion-success/

          Roy

A very helpful article for a start. Nice catch.


It does mention Carl's Ford Parts as a carburetor source.

I have a question about that for someone in the know? I can't get i touch with them. They don't answer the phone or reply to my messages. I haven't been able to figure that out?

My best guess is Carl is avoiding me and my NY addresses? Any ideas on this?

[gt350hr]

"Small block" carbs should face FORWARD. That is the way Ford intended them to be run.

   BTW The carbs actually used on the '67 T/A cars were BJ/BK (2804/2805) there are several period pictures of the Titus car in the Peterson Engine Annual showing the ink stamped numbers. It was Jerry who complained about the erratic nature of the vacuum carbs in a road race situation prompting Harold Droste (rip) to create the mechanical secondary versions. The '67 John McComb car (#33) has an original pair of these first design , non center squirt , mechnical secondary 2804/5 (SK) carbs. I have some too as well as the second and third designs.
    Randy

[shelbydoug]

"Small block" carbs should face FORWARD. That is the way Ford intended them to be run.

   BTW The carbs actually used on the '67 T/A cars were BJ/BK (2804/2805) there are several period pictures of the Titus car in the Peterson Engine Annual showing the ink stamped numbers. It was Jerry who complained about the erratic nature of the vacuum carbs in a road race situation prompting Harold Droste (rip) to create the mechanical secondary versions. The '67 John McComb car (#33) has an original pair of these first design , non center squirt , mechnical secondary 2804/5 (SK) carbs. I have some too as well as the second and third designs.
    Randy

Oh yes great and gifted wise one! Ahoom, ahoom! Shush, I'm in Temple. 


I actually tried to buy a set of the Holley continuation 2804/2805 carbs from Branda, who was out of stock and then Carl's who I could never get in contact with (still to this day).

I tried three sets of carbs. The first were two '94 Mustang GT 4180's converted to 4150 bowls. Initially, I liked the idea of the 14.6 idle. Those were ok but when I tried to richen the idle by installing 4-40 set screws into the idle well I killed the idle.

They just don't take that modification like a 1850 does.


Then I needed to set up my 3300 and 3301 that I am going to use on my GT500, so I installed them expecting them to be disastrously too big. Guess what? No they aren't too big and the engine kind'a loves them. That worked out since I had the 427 linkage to mount them backwards like the FE's do. Who knew that was going to be sacrilege?

Then I rebuilt a pair of 1850-1's and find them about the same as the 3300 and 3301's.


I had them installed forward but 1) didn't like the proximity (closeness) to the distributor cap and 2) the reproduction linkage for the forward mount, needs some considerable modification to make it work right. So backwards they are.

Years ago when I was young, handsome and foolish I had my Olds 442 burn to the ground because of a short from the distributor to the carb line. So I'm naturally apprehensive about anything that volitile close to something like a distributor cap which can crack and short out to a carb? Color me needlessly worrisome?

Now I'm older and can't run as fast (45/400) to get far enough away from the fire in time.



Who knows, in the future in a fit of righteous indignation, I may decide to flip them around again? I wouldn't want to be ostracized at the next SAAC meeting and called impure, have my buttons cut off,  forced to turn in my CS insignias and drummed out of the Corps? Ya' never know!

I still have a pair of 1848's sitting here expecting that to be the right carbs but at this point I don't think that I will bother with them at all?

[gt350hr]

   The 1848 was used as a basis for the C6OF AA and AB which were slightly different calibration and of course different choke ( and lack of) as well as the special secondary "lids" for linking the vacuum diaphrams , plus the linkage studs.
   Doug , no surprise the 715s (3300/3301) are better. The BJ/BKs were used to limit upper HP and keep the rods from exiting.
   Run your 347 carbs backwards. You were never a conformist. Watch #1 cylinder as it might run lean without a primary on top of it.
   Your constant source of irritation from Commifornia. Have a happy New Year.

[shelbydoug]

   The 1848 was used as a basis for the C6OF AA and AB which were slightly different calibration and of course different choke ( and lack of) as well as the special secondary "lids" for linking the vacuum diaphrams , plus the linkage studs.
   Doug , no surprise the 715s (3300/3301) are better. The BJ/BKs were used to limit upper HP and keep the rods from exiting.
   Run your 347 carbs backwards. You were never a conformist. Watch #1 cylinder as it might run lean without a primary on top of it.
   Your constant source of irritation from Commifornia. Have a happy New Year.

irritation = enlightenment 

[TA Coupe]

I was bored and felt like stirring up this pot. Always works when Doug is around. Here's a little carb and intake porn to add to the mix.

      Roy

[TA Coupe]

Some more

        Roy

[shelbydoug]

Some more

        Roy

You always have great porn. You are the only one that I know that puts intake manifolds out as Christmas decorations?

Doesn't the wife tell you to keep them off of the Dining Room table?

Is there an dual Dominator for inline valve heads?

[TA Coupe]

No dual dominators for inlines.
My wife doesn't mind where I have things as long as I sell something every once in a while.. She even puts up some of my car posters around the house and occasionally rotates some of my models around various rooms. She has some of my car stuff in the dining room, front room, family room, kitchen and even in one of the bathrooms. She even helps with cleaning the mancave in the house and the garage🤩

        Roy

[427heaven]

I think it boils down to the haves and the have nots. Some have some, some dont, but all want them!

[shelbydoug]

I was bored and felt like stirring up this pot. Always works when Doug is around. Here's a little carb and intake porn to add to the mix.

      Roy

On that Shelby 2x4 Boss 302 manifold, the rear overhang appears to be more then on the C60A? My rear carb is pretty close to the firewall.
Does that even fit in a Mustang?

[Drew Pojedinec]

That article didn't really tell you anything other than "buy new carbs, and have them installed and tuned by professionals."

Pros that couldn't tell their dual 600s aren't 600s 😂

[shelbydoug]

That article didn't really tell you anything other than "buy new carbs, and have them installed and tuned by professionals."

Pros that couldn't tell their dual 600s aren't 600s 😂

I don't think there was enough time in investigating the variations for the article? It grasped some of the significance but missed some that I've already realized. Of course so far for me it's two years worth. There is probably more that I haven't investigated too?

There is some discovery necessary on the 2x4's. So far it's taking me where I didn't expect to go?


I was kicking around two 4776 double pumpers but don't know how to do a secondary side hung bowl with an accelerator pump to get them to fit the manifold? That MIGHT be interesting...maybe?
See. This is why I never get done. 


In assembly of my 428, I went with the best aftermarket rods now available. That's a nice block. Wouldn't want to hurt it.