[Cruisin63]

On the tripower intakes, how are the runners separated? In other words, which barrels of which carbs feed which cylinders? Man, lots of whiches! I'm under the impression that the center carb feeds all the cylinders, but the outer ones add to it.

 

[KULTULZ]

On the tripower intakes, how are the runners separated? In other words, which barrels of which carbs feed which cylinders? Man, lots of whiches! I'm under the impression that the center carb feeds all the cylinders, but the outer ones add to it.

Usually, it is a dual plane. All carbs dump into a split common intake plenum. Now there are (were) single plane options but I doubt if you will ever see one.

 

[Cruisin63]

So it acts like a 4bbl dual plane? That's what I figured, but I was hoping for more specifics, like the driver's side of the center carb feeds cylinders_ _ _ and _. The driver's side of the front carbs feeds, blah blah, you get the idea. You can't quite tell by looking as some of the paths flow under the carbs. I guess I could pull them all off and look inside better.

 

[one37tudor]

Yes it is a dual plane low riser manifold and should have a 330 cfm center crab and two 300 cfm carbs. Good low RPM set up but drops off a lot after about 5000 rpm.
Because 2V carbs are rated at 3 inch vacuum drop rather than the 1.5 used for 4V carbs they only flow about 70 percent of their rated value when using the 4V vacuum test numbers. This means that if you are using the stock ford carbs you have approximately the same flow as a 650 cfm 4V carb. Under carbed for anything over 5000 rpm.

Scott...

 

[Cruisin63]

I can get flow out of them, just interested in the runner configuration.

 

[KULTULZ]

So it acts like a 4bbl dual plane? That's what I figured, but I was hoping for more specifics, like the driver's side of the center carb feeds cylinders_ _ _ and _. The driver's side of the front carbs feeds, blah blah, you get the idea. You can't quite tell by looking as some of the paths flow under the carbs. I guess I could pull them all off and look inside better.

Yes, same theory. The 4 X 2 dual plane intake is also the same theory.

Let me try and explain. Hopefully this will not open a fifty-plus post diatribe.

Picture below is an early BIRD 3 X 2 dual plane intake. As you can see by the casting detail(s), all three carb pad plenums are joined. This is necessary for all cylinders to be able to draw from the center carb while cruising.

You should also be able to see (barely) how the carb(s) plenum floors in the intake are divided, one side(s) low, and the other side(s) high. The runners are connected to these split plenums, i.e. cylinders # 1,4, 5 and 8 to the high port(s) and cylinders # 2, 3, 6 and 7 to the low plenum (attempting to equalize runner length(s).

The fuel is dawn into the plenums by air flow (or vacuum if you wish) and hopefully becomes fully suspended into that air flow and then each cylinder draws from the plenum(s) as each cylinder intake valve opens.

Does this help and/or confuse?

Also shown is a single plane 3 X 2 intake that will show the differences in intake types.

 

[Cruisin63]

Perfect! Thanks, no confusion at all. I am VERY picky about carb tuning. I have restricted the outer carbs IRF's a lot in hopes to add just enough additional flow from them to help balance out idle mixture. I pulled the center one down a bit too, but not as much. I can verify even idle distribution at the header primaries with a laser thermometer, but will probably hold off on major specialized tuning until after I hook up the wideband.

 

[one37tudor]

Kultulz, can you tell me what that single plane is? I don't recall ever seeing one before for an FE?

Scott...

 

[KULTULZ]

Kultulz, can you tell me what that single plane is? I don't recall ever seeing one before for an FE?

Scott...

Sure... I can try.

A single plane intake does not have the split carb plenum and the runners go directly to the cylinders (via the heads). There is no over and under flow to hopefully produce low end torque and keep the fuel in suspension.

It is meant for a HI-RPM engine (race or hot street) as it will give drive-ability problems on an everyday car including one that is mildly modified.

Two types, wet and dry. Wet (flow) refers to the fuel being suspended in the incoming air flow (CARB-TBI) and dry (flow) refers to EFI as the fuel is introduced @ the intake valve and fuel suspension is of little concern,

Does that explain it or do I (and/or others) need to go deeper? I am sure you can GOOGLE and there will be much tech info available.

 

[Cruisin63]

I don't think he was asking what a single plane does, but rather who makes that one. I'm curious too.

 

[KULTULZ]

I don't think he was asking what a single plane does, but rather who makes that one. I'm curious too.

:frown: ...sheesh...

Reading comprehension was not one of my strong points.

The intake shown (3 X 2) was FORD XE and not released for service to the general public (you had to know someone who knew someone).

You would have to go to TUNNEL PORT (4V intake shown) (good luck) to find an actual FE single plane.
_____________

LOOK HERE- Carl's Ford Parts

This is a TUNNEL WEDGE W CARBS. They also offer the bare intake.

 

[one37tudor]

Thanks for the explanation and yes I was just wondering who made the manifold.
It reminded me somewhat of the old PSE base manifold that was made for the FE's but I could not see any attachment points in the photo shown?

I have been looking for a single plane FE medium riser multi-carb manifold that has exposed runners and good flow numbers that I could install my fuel injection system on and that one looked like a possible candidate.

But as it is not in production I will likely wait to see if Jay Brown is successful in reproducing the PSE base.

Thanks,

Scott...

 

[Cruisin63]

Yeah, that thing is pretty wicked. Thanks for the info. Looks like the 3 duece will have to do for me.

 

[PSIG]

On the tripower intakes, how are the runners separated? In other words, which barrels of which carbs feed which cylinders? Man, lots of whiches! I'm under the impression that the center carb feeds all the cylinders, but the outer ones add to it.

To be clear, most 3x2 intakes are dual-plane (also known as 180°). All the carbs feed all the cylinders, but all of the left barrels are connected to 4 cylinders with one plenum, and all the right barrels are connected to the other 4 by the second plenum. While there are rare exceptions, the vast majority of even-fire 90° V8 engines (everything 1960's and up, including the FE) are divided with one side of the barrels feeding cylinders 1-4-6-7, and the other barrels feeding 2-3-5-8. Other brands use the same layout, but the cylinders are numbered differently.

See the modified pic KULTULZ originally posted below. Remember, it's the bottom. The area highlighted in RED is the exhaust heat crossover section between the heads. The runners highlighted in BLUE are the lower plenum feeding cylinders 2-3-5-8. The GREEN runners feed cylinders 1-4-6-7. The plenums are called upper and lower, as it would be difficult to cross the runners if they were all on the same level.

This is often known as the "W" runner pattern, and is used universally on all brands of American V8 engines due to the cylinder layout and crank geometry. Likewise, modern EFI versions use something more like a single-plane manifold, yet the injectors of batch-fire engines are wired to fire in the same "W" order as a dual-plane, and also the 'limp home' mode of sequential injection engines when firing injectors in batch mode.

David

The bottom of a typical dual-plane manifold, showing the two planes feeding which cylinders:

 

[PSIG]

Here's a better overhead to show the runner routing each barrel set feeds.

David

 

[Cruisin63]

Look at all the pretty colors! Lol. Thanks guys, that helps a lot. I never really thought about it being the same as a typical dual plane, but it makes a lot of sense. That will be especially helpful for someone super anal like me when it comes to AFR and even fuel distribution.