Differences in 2.9 Twin Throttle Body Intakes

[PetroleumJunkie412]

Had two European intake manifolds for the 2.9 shipped over from the UK. Just a photo thread showing differences in three different twin throttle body 2.9 upper manifolds - two generations of Euro manifolds versus the American version.

Have a Merkur lower on the way (very different port shape). Will update with photos of lower intake differences as well.

Biggest differences at a glance:

No EGR port on the UK throttle body

No IAT sensor port in UK manifolds

Missing center rear vacuum port in both UK manifolds. The Merkur Scorpio intake has a drilled and tapped port in the back that allows both sides of the manifold to equalize pressure. This is for the MAP sensor. This port is blank on both UK manifolds. Guessing this is due to most European cars using vane air meters versus the American cars using MAP sensors.

Black UK manifold has a different PCV port

Euro throttle body missing cruise control cam and return spring.

The gaskets on one if the European manifolds contain two extra holes that are not present in the Ranger lower. Still searching for the lower that gasket fits.




More to come

 

[mnewman]

Interesting. I'm still learning the 2.9. Back in one after 21 years.

 

[DavisRanger]

Had two European intake manifolds for the 2.9 shipped over from the UK. Just a photo thread showing differences in three different twin throttle body 2.9 upper manifolds - two generations of Euro manifolds versus the American version.

Have a Merkur lower on the way (very different port shape). Will update with photos of lower intake differences as well.

Biggest differences at a glance:

No EGR port on the UK throttle body

No IAT sensor port in UK manifolds

Missing center rear vacuum port in both UK manifolds. The Merkur Scorpio intake has a drilled and tapped port in the back that allows both sides of the manifold to equalize pressure. This is for the MAP sensor. This port is blank on both UK manifolds. Guessing this is due to most European cars using vane air meters versus the American cars using MAP sensors.

Black UK manifold has a different PCV port

Euro throttle body missing cruise control cam and return spring.

The gaskets on one if the European manifolds contain two extra holes that are not present in the Ranger lower. Still searching for the lower that gasket fits.




More to come



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Did you throw one on your truck? If so, what did you do for the IAT and EGR? I need one of these. Lol

 

[RonD]

I wanna know why there are TWO intake ports and throttle plates for ONE engine???

I get dual and triple carbs, but this is fuel injection at the intake valves

It can't just be for looks, so whats the science for it?

 

[Dirtman]

Because there's twice as many! More is always better.

 

[DavisRanger]

I wanna know why there are TWO intake ports and throttle plates for ONE engine???

I get dual and triple carbs, but this is fuel injection at the intake valves

It can't just be for looks, so whats the science for it?

I would assume to allow the engine to breathe more? From my understanding, these breathe better than the American 2.9 upper manifolds.

 

[Dirtman]

I would assume to allow the engine to breathe more? From my understanding, these breathe better than the American 2.9 upper manifolds.

Still doesn't explain the need for TWO. If the single throttle body bore was restrictive, that problem can be solved by just using a larger single throttle body.

 

[RonD]

Gasoline engines "suck", lol, they don't breath, they are more like fish, air passes thru, comes in one opening and goes out another

So one larger opening with one throttle plate is not as good as two smaller ones

I guess a case could be made for less turbulence or building up a pressure wave

 

[Dirtman]

Then why not 6 individual throttle bodies? Eh?

 

[RonD]

Then why not 6 individual throttle bodies? Eh?

oh, I like that one, velocity stacks for V6's with 6 throttle plates, like you said, if one is good, and two is better then SIX is WOW

There is a simple but not altogether easy test to see if you have restricted air flow on any normally aspirated gasoline engine
A Vacuum gauge, I know duh
But you have to mount it in the cab or someplace you can see it at high speed
Then find a place with no cops and get to top speed WOT, you want to see about 1" of vacuum before valves float, if its 2" or more air is restricted, from something, may not be throttle opening, but can be
If it drops to 0" before valves float your exhaust flow is the issue

 

[Ranger101]

Had two European intake manifolds for the 2.9 shipped over from the UK. Just a photo thread showing differences in three different twin throttle body 2.9 upper manifolds - two generations of Euro manifolds versus the American version.

Have a Merkur lower on the way (very different port shape). Will update with photos of lower intake differences as well.

Biggest differences at a glance:

No EGR port on the UK throttle body

No IAT sensor port in UK manifolds

Missing center rear vacuum port in both UK manifolds. The Merkur Scorpio intake has a drilled and tapped port in the back that allows both sides of the manifold to equalize pressure. This is for the MAP sensor. This port is blank on both UK manifolds. Guessing this is due to most European cars using vane air meters versus the American cars using MAP sensors.

Black UK manifold has a different PCV port

Euro throttle body missing cruise control cam and return spring.

The gaskets on one if the European manifolds contain two extra holes that are not present in the Ranger lower. Still searching for the lower that gasket fits.




More to come



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View attachment 35466

Would the Merkur manifold with the twin throttle body fit on a 2.9l in an 89 Ranger?

 

[PetroleumJunkie412]

Would the Merkur manifold with the twin throttle body fit on a 2.9l in an 89 Ranger?

all euro/Merkur intakes fit all 2.9l 12 valve engines. The hard parts are the bolts, throttle linkage, and gasket sets.

Did you throw one on your truck? If so, what did you do for the IAT and EGR? I need one of these. Lol

No EGR on mine, and standard 2.9l IAC fits. TPS sensor is difficult, but is a volvo sensor anyways. Merkur Midwest and Merkur Depot both carry them.

I wanna know why there are TWO intake ports and throttle plates for ONE engine???

I get dual and triple carbs, but this is fuel injection at the intake valves

It can't just be for looks, so whats the science for it?

Has to do with intake scavenging at high RPMS. The Ranger intake falls on its face after 3500 RPM or so according to the VE maps from mine.

I would assume to allow the engine to breathe more? From my understanding, these breathe better than the American 2.9 upper manifolds.

Yep. Tested both, ported and unported. Merkur one needs nearly no porting.

Still doesn't explain the need for TWO. If the single throttle body bore was restrictive, that problem can be solved by just using a larger single throttle body.

Scavenging.

Gasoline engines "suck", lol, they don't breath, they are more like fish, air passes thru, comes in one opening and goes out another

So one larger opening with one throttle plate is not as good as two smaller ones

I guess a case could be made for less turbulence or building up a pressure wave

Yep.

Then why not 6 individual throttle bodies? Eh?

Hillclimb n/a versions do use 6 throttle bodies. The intake port runners on the heads are high velocity ports, so they tend to function best with the shortest runner possible.

There is a simple but not altogether easy test to see if you have restricted air flow on any normally aspirated gasoline engine
A Vacuum gauge, I know duh
But you have to mount it in the cab or someplace you can see it at high speed
Then find a place with no cops and get to top speed WOT, you want to see about 1" of vacuum before valves float, if its 2" or more air is restricted, from something, may not be throttle opening, but can be
If it drops to 0" before valves float your exhaust flow is the issue

Has been done. Engine vacuum shows back up at 3500 rpm or so with the truck intake (on a bad cam as well). Tb size on the truck intake makes no difference.

 

[RonD]

OK, well that makes sense

 

[Dirtman]

NOTHING MAKES SENSE!

 

[sheep herder]

NOTHING MAKES SENSE!

Pennies make cents.