Cobra Carter dual quad question

[livetoride60]

Not sure if this is the correct forum, but looking at a Cobra dual quad for sale, but don't think it has the correct Carter carbs.  It has j2-9400s but reading correct ones should be 3258S and 3259S. 

Also, was the Cobra Carter dual quad intake ever reproduced?  I read the Holley version was.

If anyone can confirm, or provide more info on how to authenticate, it would be appreciated.

Thanks,
Rich

[shelbydoug]

Blue Thunder is the one reproducing the Ford SB 2x4. The Carter 2x4 was a very early introduction and seen offered on SB Cobras.

It is not a particularly high performance design. It is similar to the 2x4's offered on GM's of the time.

It's a low riser design and you shouldn't expect anything spectacular out of it.


The Carters that you mentioned are the original list numbers but probably aren't of interest to anyone but a 289 Cobra owner that had them new on the car?

They're more of a curiosity. The Holley set up is a better concept offer 3x2's and 2x4's.


Randy (GT350R) calls it the "slug" but it just needs a little port matching to wake it up. Having run it I can tell you that it makes nice power and is a bit unique to drive.


...but no. No reproductions of the 2x4 Carter COBRA that I am aware of.

[427heaven]

This topic comes up once in a while and the general consensus is that they are not reproduced. As with anything from almost 60 years ago there has been major performance improvements but if you are looking for a good boost of performance and a totally cool look under your hood run it. I run one and have over the last 40 years and couldnt be happier. They run good , look good, and have that wow factor when you pop the hood. You will be the only one on your block with one as I have been in my neck of the woods. Same with the early VETTE or HEMI or COBRA.... Old is Gold, modern parts- are your true go fast friends.

[livetoride60]

Thanks for the feedback.  I'm considering it even if it doesn't have the correct carbs, obviously the price has to reflect that. 

As you said 427heaven, it will look cool under the hood and add some pop to my 289 hipo.

Thanks,
Rich

[Bob Gaines]

Not sure if this is the correct forum, but looking at a Cobra dual quad for sale, but don't think it has the correct Carter carbs.  It has j2-9400s but reading correct ones should be 3258S and 3259S. 

Also, was the Cobra Carter dual quad intake ever reproduced?  I read the Holley version was.

If anyone can confirm, or provide more info on how to authenticate, it would be appreciated.

Thanks,
Rich

My advice is to resist the urge. If you want duel fours get the later Ford intake/intakes designed for the Holley carbs. There is a reason/reasons that the carter set up went extinct . Best of luck what ever you decide.

[shelbydoug]

This is a better and more impressive set up I think then the Carters? Likely cheaper as well.

I agree with Bob on this. IF you're gonna' take a plunge, if you insist, do it right!
It is kinda' like a plunge. Like you plunged off a cliff when you open them up.

Green Peace is gonna' hate you. Don't let them see it. 


You have to hear the secondaries when they open up? It's like a racing sail boat when you open the big sail. There's this big "WHOMP" !

These are the List 3300/3301's. You would think it was drastically over carb'd wouldn't you? You'd be drastically wrong! I was shocked. My whiplash will heal soon I think?

2 1850's work nicely also. There is no room left to fit carbs. The back one is right up against the firewall and the front about 1/2" from touching the distributor cap.


Think of this set up as a double pumper (of your choice of size) with vacuum controlled after burners like a fighter jet has. The only thing is that they will feed into your narcissism and if you didn't have any before, you will after.

I don't know who originally conceived of this but they are very dangerous individuals?

[Side-Oilers]

Dual fours plus A/C is Cool Squared.

[shelbydoug]

Dual fours plus A/C is Cool Squared.

Well I'm just too cool to stand myself. 

Next time I have a stuck float, flooding, can't get the fuel level right, and burn myself on the headers again, remind me how cool I am, 'cause I forget that kinda' stuff real fast and maybe I'll believe you, ok?

It's my coolness that always has me in trouble but foolishness is a more accurate term?

[427heaven]

Same couple guys talking about this for years... Nice looking Doug, just lacking the early Cobra heritage 62- 63 - 64.

[shelbydoug]

Same couple guys talking about this for years... Nice looking Doug, just lacking the early Cobra heritage 62- 63 - 64.

True. This is the C60A "Trans Am" intake. That was for the Cobra's little brothers.

The Carter preceded even the over the counter "High Riser" by at least two years.

A 289 Cobra would be more correct with the Carters admittedly. You might want to look at that linkage though to verify that it is progressive. As I saw it, they were tied together and ran on both carbs all the time?


The Ford 3x2 Holley's that Jeff Burgy ran all of the time is a very nice set up as well on a 289. I'm cheating here a bit with a 347 kit stuffed in, so the cubes do help.

I'm just showing off the wares here like the Devil. Just attempting to corrupt another poor soul to a lifetime of "Holy sh it skis". Me bad.

[Dan Case]

Shelby American started installing 2-4V induction as a new Cobra factory option in September 1963 based on new car invoices. The first well known COBRA high rise intakes came out in 1965 MUSTANG GT350s in late 1964.

[shelbydoug]

Shelby American started installing 2-4V induction as a new Cobra factory option in September 1963 based on new car invoices. The first well known COBRA high rise intakes came out in 1965 MUSTANG GT350s in late 1964.

Yes. No argument but the 2x4 SB Holley set up was only over the counter. In SOME catalogs that intake manifold is referred to as a 2x4 "High Rise". That is what I was referring to. Not the single 4v COBRA high rise.
They don't even show up until around '66.



Back in the day I only saw one 289 Cobra with the dual Carters and he would run against 427 Cobras neck and neck. So I wouldn't call it all looks.

It had the American Racing wheels on it as well so we always thought it might be one of the Dragonsnakes at the time. Legends and speculation always abounded around Cobras then.


Holleys have got their problems. They just became popular because of their tuning ability. I will admit that two Holleys on the same set up are probably four times as difficult to deal with when something is wrong as only one is?

So far for me most of the issues focus on linkage issues.


The OP did not state what he was considering the setup for.

[Drew Pojedinec]

Good.... So I guess you can stop telling people that a single 715 is way too big for a 289 eh Doug? 😂😂😂😂

715 is a great size in a Holley due to venturi/throttle bore relationship.
For a driver, I'm more of a fan of the 3x2 setup, but for all out power, it is hard to beat 2x4.
If you want a hybrid, building two 1848s is a worthy venture.

Oh and regarding the float issue, remember the carbs are backwards and probably not level. Most backwards 2x4s run way better with the secondaries a hair lower than normal. (Yes the float level can richen the a/f ratio even at idle)

[shelbydoug]

Good.... So I guess you can stop telling people that a single 715 is way too big for a 289 eh Doug? 😂😂😂😂

715 is a great size in a Holley due to venturi/throttle bore relationship.
For a driver, I'm more of a fan of the 3x2 setup, but for all out power, it is hard to beat 2x4.
If you want a hybrid, building two 1848s is a worthy venture.

Oh and regarding the float issue, remember the carbs are backwards and probably not level. Most backwards 2x4s run way better with the secondaries a hair lower than normal. (Yes the float level can richen the a/f ratio even at idle)

Yes I do still think a 715 is too big on a 289 in a single 4 on the street. Even on the track I find them flat and lacking crispness. I'm constantly waiting for the power to come on. I feel like I can be checking my email?

If I might quote Ford on that subject here, "a 600cfm carb on your small block Ford is all you need except if you are intending to run at Lemans". That's the horses mouth if you ask me.



Two 600's on a Ford 2x4 intake is not to big at all. It has to do with the throttle opening progression and the throttle crispness that is maintained. I'm not running a 289 though. It's a 347 with AFR heads. A bit of a different animal.

To me, a 4776, 600cfm double pumper is way more responsive then a 715 ever was or ever will be.

Just two 1850's with progressive linkages are similar to a single 4776 response wise but with after burners opened by engine demand and a way better intake manifold then the S2MS Cobra.



In all fairness to Holley though, what has to be considered here is the intake manifold design. All of the Ford 2x4 intakes have better fuel distribution then even the COBRA S2MS intake does.

What is now run in "Vintage" is a Blue Thunder S2MS which has additional runner volume cast in and even those manifolds are internally reworked but don't say anything that is a secret no one is supposed to know?



The two small block 2x4 Holley intakes both have wide open throttle characteristics of an individual runner intakes, particularly the C6OA "Trans AM" intake and it's variants. That affects throttle crispness and fuel distribution. As cast it has nearly identical runner lengths of around 4.5 inches. A number that the Weber intake manifold design people claim is about optimum.

I only have one FE intake, that's my C7ZX "mediumn riser". It could be a lot better but I think the main issue with that one is lack of "line of sight" to the valves and runner lengths being too long?

So while you are talking about optimum throttle venturi ratios of the carburetors, I'm talking about the complete package results.



So what's it to you about which carb is "good" and which is "not so good"? You're gonna' get 'em all to restore anyway. And you should. I can't think of anyone who does better work on Holleys then you. The only problem with your carbs are they are too pretty to get dirty! 


Here is what the '66 289 Ford High Rise looks like.

[Drew Pojedinec]

Eh, venturi to throttle bore relations truly help with even, clean fuel draw.
Running a 3300 vs a 3259 is a different animal. Not to mention there are several distinct 3259s that act waaay differently. Sadly the list 4118 and later 3259 reproductions mimic the calibration of what I consider to be the worst and most unusable 3259 variant.
3300/3301 also have a different booster, booster pin and notches make a difference.
If you like the 715s for 2x4, you'd love the 652s. They are pretty neat, probably why they saw so much use as factory race gear.

I understand intake differences, I often make small adjustments depending on what the carb is being bolted to.

Two reasons your single 715 experience is weak.
You are running a particular variant. If it lacks the proper idle feed your a/f ratio goes rich/lean/really really rich/ lean again.
Carb lacks vac secondary amplifier and doesn't open secondaries fully. The longer vs diaphragm causes that to happen as well. Cracking the secondaries and them not opening often gives a super dead feeling. Anyway, could ramble about this forever.