Dual inlet manifold - installation

Today I got my new dual inlet manifold from Fourby.

Asa i'm currently waiting for my turbo rebuild to come back, i'd thought i'd just start off by posting some pics of the manifold adding pics as I fit and test.
I've also fitted a larger intercooler (see here https://www.landyzone.co.uk/land-ro...ort-full-size-intercooler-to-a-300tdi.361322/ ). The dual inlet manifold is designed to give a more balanced flow to the inlet ports on the cylinder head - which makes sense.



The manifold comes with 2 intercooler elbows (part # ESR2730 / PNH102082) and 4 off 40-50mm jubilee clips (not pictured). One of the hoses has been trimmed slightly, no doubt that will become apparent (why) when I offer it up to the head.

Put in and lined up. Not connected as i'm waiting for my turbo rebuild to come back ...

I`m struggling a bit with the logic on this, surely if the standard inlet manifold is pressurized by the turbo as soon as an inlet valve opens that pressure will enter the cylinder regardless of where the turbo feeds in? If we were talking about an non turbo engine then the direct feed will be beneficial, by the way i do really like it and if i ever upgrade my 19j to a 200 i will definitely be making one of those.

From the website .... These manifolds are individually tuned on a flow bench to maximise and balance the flow of air to the inlet ports on the cylinder head.
Each manifold is fine tuned to give a balanced air flow across all ports. When you supply each cylinder with the same precise dose of air, at the same pressure, then you harmonise the torque given to the crankshaft for every power stroke.

Which makes sense although so does your argument that if a volume of pressurised air in a plenum which is larger than the required volume behind the open valve, which can be replensided quickly enough, pressure should be equal whatever the inlet outlet arrangement is. It's going to be awfully turbulent in that plenum though and I think this arrangement makes sense in that it will smooth out the flow so that when 1 or 3 or 4 or 2 suck in they should get a more equal dose of dense, cool air.
There is the likelyhood of a bit more cooling too (I guess), every little helps.

I apologies If i am being cynical here but what else are you doing to the engine? Although what you have said above and the extract from the website may be true for high end race spec engines these landy engines are in such a low state of tune for reliability above all else I am struggling to see how this would give any noticeable improvement. And even if you start messing with things like bigger turbos, more fueling and huge intercoolers to get every last bhp from the engine I am still skeptical that with any set up of a land rover tdi engine this would have an impact.

dag019 said:

I apologies If i am being cynical here but what else are you doing to the engine? <snip>.

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No apologies neccesary
My previous 300tdi 90 was good, a bit rattley (trator like), bit smokey, slightly flat, slow to pick up and easy to bog down. It wasn't really comfortable in the rough and felt cumbersome towing my Ifor twin axle especially when laden with wood coming off the fields.
Over time I reset the valves, checked the compression, tidied up the pipework replacing the radiator and cooling/intercooler pipes etc. I fitted a boost pin and reset the fueling and smoke ring which smoothed out the power delivery, got rid of the rattles and the smoke. It was a bit better, but still a bit flat. I got the injectors refurbed and fitted a Delphi 296 fuel filter. There was a little improvement but nothing really noticable. That changed when I fitted the Alisport, uprated, dual core, intercooler and cleaned up the turbo, setting boost to 1bar (15 psi). More available power, better pickup, less gearchanges, easier to drive and tow etc. Schweet.
I borrowed an EGT guage and spent some time (4 to 6 weeks) driving in all sorts of conditions fettling the fuelling etc to ensure I never went over 630C, typical pootling around on A roads i'm below 350 as a rule and around 400/420 on a motorway. I further improved the drivability by fitting Terrafirma lightweight + 2" springs and shocks, something i've also just done to my 'new' D90.
Fresh rather than tired would be a good way to describe how it feels.
Soundproofing the cab and the tub made a big difference too.... smoother somehow, no more shouting above 55mph

Anyway - back to the engine. What I am doing to this one ? (The Squirrel - occasionally The Fokker, because its been painted grey) is getting all of the above upgrades which will make the car smooth and responsive. This time around I have fiited a full width intercooler, i've got an 'enhanced' turbo core and have a 17psi uplift. I've not fettled the fuelling as yet but have fitted a boost pin and a pump timing spacer. Once i'm up and running i'll go through the same proceedure with EGT as I did before and optimise the fuelling.

My original D90 (which is for sale BTW) has the original 1995 engine with circa 120K miles. My new one has a 2014, LR refurbed engine with just 12K under it's belt. If I can make it comfortable by ensuring it always breaths cool dense air, drinks the right amount of fuel and farts exhaust gas without impediment then it will satisfy my quest for mechanical sympathy and longevity, it won't get raced, rolled or rallied and we'll get along just fine.

I know this is an old thread, but I'm fitting a new head and would like a Tdi Twin Inlet Tuned Manifold. However they do not seem to be available anymore.
I've tested air forced into the manifold and with paper over the ports can measure the flow visually.
The air hits the back and gives more pressure to cyl 3 and caused some scavenging from cyl 1 and 2. Look at pic.
So the Tdi Twin Inlet Tuned Manifold would help a more balanced air supply and not have cylinder 3 doing more work.

Thats technical .
Thing is when the valves are closed to that cylinder where does the air go?
All the forced air would go into the cylinder with the inlet valve open.

As for flow of the double, well yeah maybe.

J

Have you ever wondered why it's always cylinder no 3 that blows the head gasket.
I would like to make one of these or buy one, but cannot find any available. So may buy a couple of old inlet manifolds and see if my Aluminium welding is good enough
Have a new head and gas flowing and polishing the ports and bowls, for a slightly better all-round driving experience.

I fitted a go faster stripe to my 110 200tdi. Starts to peel off at speeds above 106 mph though.
Before you all take the pizz, I've got +20 thou pistons so it's a 4.3 litre or there abouts .

Wagon Loon said:

Have you ever wondered why it's always cylinder no 3 that blows the head gasket.
I would like to make one of these or buy one, but cannot find any available. So may buy a couple of old inlet manifolds and see if my Aluminium welding is good enough
Have a new head and gas flowing and polishing the ports and bowls, for a slightly better all-round driving experience.

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I don't know the reason for the head gasket issue.
Flowing ports from the manifold to the cylinder will improve flow of air (so more can get in) It means the volume of air available might be lower as the pressure drop will be more maybe. But with a turbo should be plenty.

I am by no means an eggsquirt on the engine but shirley there are mods to do between the turbo and the engine that restrict it more than the inlet manifold? Its never gonna be a performance car.

J

I need some of those

Wagon Loon said:

Have you ever wondered why it's always cylinder no 3 that blows the head gasket.
I would like to make one of these or buy one, but cannot find any available. So may buy a couple of old inlet manifolds and see if my Aluminium welding is good enough
Have a new head and gas flowing and polishing the ports and bowls, for a slightly better all-round driving experience.

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I thought it blows between 2 & 3 as it’s the smallest part of the gasket?

Wagon Loon said:

I know this is an old thread, but I'm fitting a new head and would like a Tdi Twin Inlet Tuned Manifold. However they do not seem to be available anymore.

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Have you tried contacting Fourby? I think they only make them to order, so a phone call might sort one out for you.

marjon said:

I don't know the reason for the head gasket issue.
Flowing ports from the manifold to the cylinder will improve flow of air (so more can get in) It means the volume of air available might be lower as the pressure drop will be more maybe. But with a turbo should be plenty.

I am by no means an eggsquirt on the engine but shirley there are mods to do between the turbo and the engine that restrict it more than the inlet manifold? Its never gonna be a performance car.

J

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Performance is relative, as is efficiency, not sure why you'd prefer a less efficient engine or one that potentially makes less power???

Intake manifolds come in all sorts of shapes and sizes and can seriously impact performance. Lots and lots of documented tests in written articles and videos. Why are you so adamant that a Tdi engine won't respond to a different manifold design?

When I seen all the craggy intrusions from casting on the otherwise shiny new head, I figured it was the perfect opportunity to remove the intrusions into and smooth out the ports. Since it's direct injection the fuel mixing in the piston, allows for the inlet ports to be polished too.
I have not changed the shape or made exhaust ports bigger as indeed this can slow the airspeed down and loose low down torque. it's more tractor than hi revving engine.
But some sensitive cleaning of the airways is just like blowing your nose, and polishing which is taking me a very long time because I'm no pro, is free horses and could improve economy and responsiveness.

I'll also lap the valves with 300then 600 grit paste for a better than factory cut seal. There's often some chatter in the seats from factory and lapping can quickly show this and with a very fine finish of 600,get a better seal.
I know she's just an old truck, but she drives really nice, off roading in my small woods several times a week.
The too of the inlet spiral air path was particularly cruddy ant this is where the air is moving fastest, and this is actually them cleaned up quite a bit!
Still lots of polishing to do before lapping the valves.
Bit like fishing really

300bhp/ton said:

Have you tried contacting Fourby? I think they only make them to order, so a phone call might sort one out for you.

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That's a great idea,
Thanks I'll contact them and ask

300bhp/ton said:

Performance is relative, as is efficiency, not sure why you'd prefer a less efficient engine or one that potentially makes less power???

Intake manifolds come in all sorts of shapes and sizes and can seriously impact performance. Lots and lots of documented tests in written articles and videos. Why are you so adamant that a Tdi engine won't respond to a different manifold design?

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I have no issue with the different performance of inlet manifold design. But there is stuff that needs sorting before that.

300bhp/ton said:

Why are you so adamant that a Tdi engine won't respond to a different manifold design?

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I am not...
But air in, air out. So lets start at the air in first. How does it get to those inlet ports (and they look lovely in those pics) before we even think about getting it out.

J

@Wagon Loon , you may like to scuff up those inlet ports, they're too smooth/too polished. Too smooth an inlet port causes larger fuel droplets to form which is not what's wanted. Ideally, all heads [petrol and diesel] need some level of coarseness to enable constant air-fuel mix.

v8250 said:

@Wagon Loon , you may like to scuff up those inlet ports, they're too smooth/too polished. Too smooth an inlet port causes larger fuel droplets to form which is not what's wanted. Ideally, all heads [petrol and diesel] need some level of coarseness to enable constant air-fuel mix.
View attachment 313106

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The 300 TDI is a direct injection engine, so there is no fuel in the inlet ports and the directly injected diesel mixes inside a small bowl inside the piston.