FE 2X4 Opinions

[larryar]

I love carbs! I know there are more efficeint meathods out there, but a Cobra is from the 60's. When my rice burner neighbor first saw the 428 fe with 2x4's on it, he was amazed! He had never seen a 'real' motor before. I could see he still wasn't grasping it, so I asked him the size of his engine. 1,6 liters he replied proudly. When I told him mine was 7 liters, his jaw hit the floor, The final touch was firing it up in the garage........no fart pipe will ever sound like an FE!
Larry

[KobraKarl]

Well ,Gosh , Sizzler,

I guess if most of us were worried about joining the 21'st century we wouldnt be driving these raw little ball busters around any way,

Also my car dosnt float as well as yours and my family wont fit in the passenger seat..... but you got me on the road trip argument though

KK

[wilf leek]

Turk told me he loves his 2x4s.

Anytime he gets a power outage, he just goes into the garage, attempts to start the car, and voila! instant illumination.

Works as a barbeque, too.

On a serious note, is there any (properly) documented information about power output 2x4 vs 1x4 on an FE? Or torque curves?

Simplistic view would have it that 2 x 650cfm carbies are way too much cfm?

[KobraKarl]

Wilf ,

I think of it this way; I am running a four barrell with mechanical secondaries (primary 2 on each carb with progressive link) each of those 2 bbl's has its own filter, this is fine for most driving.

THEN if at higher throttle openings (wot) my engine says "how bout a little more " those precisly tuned vaccuum secondaries open just the correct amount to accommodate breathing and fuel charge at high rpms, I doubt the effective cfm used at 6000rpm exeeds 850.

and they are really shiney

KK

[Sizzler]

You're right about the sound of an FE.
I took my car to a local cruise night and it was the sound that turned heads more than anything. I don't know how many people looked me up due to the sound. Personally, I think it has to do with the length of exhaust runner exposed outside the bulk of the head.

BUT THEN, the younger ones got interested in the 2 4-barrel throttle bodies and the efi system so I was appealing to a multi-generational group.

I guess I'm younger than most here, carbs to me must be like generators to some of you. Chokes, heat crossovers, magneto's, all distant past and pretty much of interest to me at about the same level as tubes in tires. Sorry.

But 8 barrels, be they venturi or just plates, are definitely cool to me. These cars are about individual expression and desire, so please don't think I'm advocating any sort of restraint or restriction in what you do to your cars. Have fun. Be safe. Sunny day tomorrow, top down.

CFM requirements depend also on whether you're using a dual-plane 2x4 or a single plane manifold, and if a dual-plane, whether the divider is cut down or missing or whatever. Dual planes require more cfm is the short theory.

[edwhite7]

Sizzler is correct as to the carb size. A dual plane will need more carb than a single plane. If you take a close look at the runners on a dual plane you can see that only a portion of each carb is available to each cylinder. I had a dual plane with two 650 vac secondries and a single plane with two 450 mech's and I like the 450's best. I tried both progressive and non linkage and the non progressive setup is much more responsive on my car. Watch the power valves, the 450's come with 85's and the 650's come with 65's. With any cam the 85 power valves will probably be open at idle.

[Lew Ledyard]

Are there any advantages, other than cost and possibly easier tuning, to a single four as opposed to dual quads for a well built Shelby BB FE motor?

[SCOBRAC]

Yes.. less horse power (better mileage ) Of course without dual quads you will be less likely to open your hood.. But then you will keep the dust off by going that route.

[FE Specialties]

Hi Clois,

2X4s are no problem as long as both carbs are in good shape, and your careful on the initial set-up. I built a 454(428 crank) with a tunnel wedge and 2 750s. Yes 2 750's!!! I jetted down to 68 on the primaries and built 646hp on 10.4 to 1 compression!!!
One thing though, DONT Run Edelbrock carbs. I like everything that Edelbrock makes except their carbs. All they are are old AFBs that all of us used to laugh at in the 70's. They are junk!! Every motor that I have replace a Edelbrock carb with a Holley or Demon has picked up 5 to 7 tenths in the 1/4 mile. If you are running good heads with a cam over 245 .050 duration(Solid) then use 600s, if smaller, use the mechanical 450s.
Hope this helps!!!!!!!!
Tom

[Lew Ledyard]

2X4s definitely look great. Is there any driving or performance difference between a single quad and a dual quad set-up on a BB stroker motor? Are looks the only reason to chose dual quads over a single with a turkey pan set-up?

[wtcobra]

I have tried about every manifold for an FE, or my friends have tried the ones I haven't and the best intake for the FE in my opinion is the Victor for all around use. Of course I am assuming the use of a good carb on the manifold. It will be smoother and will make more power thru out the rpm range. The 58 IDAs are great but require much attention, and are quite expensive.

[Clois Harlan]

Wayne good to see you're back and doing well I assume.

Just a follow-up. I have had my 2X4 set up on my 428 for about two weeks now and I absolutely love them. Great power and there is not much else to be said about the look of 2X4's. I did need to lean my carbs out a little bit but they are running great!

Clois

[Traveller]

427 S/O,

I want to hear more about those Autolite, inline carbs!

[427 S/O]

Whatdayawannaknow........

[Traveller]

....can I have em?

[tim]

427 S/O,
My wife said she saw you last week. Said your cobra was running REALLY RICH!!! Is that the results of to much CFM? HA HA
Tim

[427 S/O]

That was tire smoke............

[tim]

I'm sorry, but my wife is a lot smarter than that. It was fuel not rubber she smelled.

[427 S/O]

Them 450 mech. are doing just fine with 61's, besides, the in-lines won't be going on for a couple more weeks. Gotta finish the air filters.

[Carnut427]

I've had 600 vacuum secondary carbs, and they ran great. Changed to a 2X4 Tunnel Wedge (single plane) with 660 cfm center squirters (had to add power valves), and they were noticeably faster on the track, with excellent driveability. Just change your oil after racing, and of course, use Mobil 1.
Good Luck,

Dan