Dual inlet manifold - installation

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
this is going to cost me money - i can feel it
there is a fairly recent thread on someone fitting a gas flowed head from Turners i think
a quieter motor and more low down grunt was the takeaway i got from the thread

here in saffer land some get the exhaust manifold powder coated and seem impressed with the results
 
Wagon Loon said:
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.
View attachment 313082View attachment 313083View attachment 313084
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! View attachment 313085
Still lots of polishing to do before lapping the valves.
Bit like fishing really
Click to expand...
I fitted the turner engineering performance head to my 200 recently, it only adds 8-10hp but drive ability is much nicer with quicker pick up and stronger mid range.
 
johnlad said:
I fitted the turner engineering performance head to my 200 recently, it only adds 8-10hp but drive ability is much nicer with quicker pick up and stronger mid range.
Click to expand...
I bought a replacement head and sold the original.
It made sense to start afresh, 27 years slightly pitted valve seats and leaky stems; the original would have cost as much to have to have a head shop refurbish the old one. Also the crud from EGR was just nasty on the back of inlet valves.
However DPD managed to drop the new head twice, slightly damaging each end of the mating surface!it was still very serviceable with some very careful removal of material but this would nolo ger have any warranty, so they very kindly sent me another, specially packed tor the careful handling of DPD people 🤣
PXL_20240218_152839947.jpg
PXL_20240218_152823790.jpg
PXL_20240218_152905319.jpg

So having two new heads and looking at the turner engineering head, and having a chat on the phone with them thought what's to loose!
Turner buy them standard and gas flow them themselves, but they're professionals and probably have a flow bench. I'm a DIY'r with the tools and the time. A professional job takes 10 hours, so if I can avoiid removing too much and do it in 40 hours; that's fine. If I Completely f it up, I have another and only need more gaskets and a lesson in humility.
I love the way Peggy the farmy girl pick-up drives compared to Gigi, my 1975 88" S3 Station Wagon anyway; but a little more drivability would be awesome.
I'm still driving my S3 every week she's just great fun
PXL_20220731_134521904.jpg
PXL_20220807_161952490.jpg
 
Last edited:
johnlad said:
I fitted the turner engineering performance head to my 200 recently, it only adds 8-10hp but drive ability is much nicer with quicker pick up and stronger mid range.
Click to expand...

Snap. I too have a TE engine with gas flow head. Our Tdi engines are never going to be flying machines but they do trundle along nicely with the TE treatment.
 
marjon said:
I have no issue with the different performance of inlet manifold design. But there is stuff that needs sorting before that.


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
Click to expand...
What do you think needs sorting?

To give another example. I have a Chevy Camaro with the LS1 5.7 V8 engine. Swapping a later manifold on gives an easy dyno proven 20hp. Same pipe work, same throttle body. Same size inlet hole on the manifold. But a slightly different internal design. The two manifolds almost look identical on the outside. So just a change in manifold can produce results.

And while this dual inlet Tdi mod is just a modification to the existing manifold. It essentially makes the manifold quite a different design.

I can’t vouch for flow testing. But I can say fitting it made an instant change to the engine. It felt smoother and slightly more peppy. Doing some timed performance runs I also saw an improvement, which would suggest a power increase.
 
300bhp/ton said:
What do you think needs sorting?

To give another example. I have a Chevy Camaro with the LS1 5.7 V8 engine. Swapping a later manifold on gives an easy dyno proven 20hp. Same pipe work, same throttle body. Same size inlet hole on the manifold. But a slightly different internal design. The two manifolds almost look identical on the outside. So just a change in manifold can produce results.

And while this dual inlet Tdi mod is just a modification to the existing manifold. It essentially makes the manifold quite a different design.

I can’t vouch for flow testing. But I can say fitting it made an instant change to the engine. It felt smoother and slightly more peppy. Doing some timed performance runs I also saw an improvement, which would suggest a power increase.
Click to expand...
I gave them a shout but they have not come back to me, so they may not be making them anymore 😭.
Maybe I buy old ones and make my own, if I can get my TIG working properly 🤣
 
300bhp/ton said:
What do you think needs sorting?

To give another example. I have a Chevy Camaro with the LS1 5.7 V8 engine. Swapping a later manifold on gives an easy dyno proven 20hp. Same pipe work, same throttle body. Same size inlet hole on the manifold. But a slightly different internal design. The two manifolds almost look identical on the outside. So just a change in manifold can produce results.

And while this dual inlet Tdi mod is just a modification to the existing manifold. It essentially makes the manifold quite a different design.

I can’t vouch for flow testing. But I can say fitting it made an instant change to the engine. It felt smoother and slightly more peppy. Doing some timed performance runs I also saw an improvement, which would suggest a power increase.
Click to expand...

You are comparing Apples to Oranges and you know it.

Normally aspirated to Turbo, Totally different.

J
 
So Fourby folk got ack to me and said there is a waiting list I can Join.
Here's the link for anybody interested in getting one too.

Tdi Twin Inlet Tuned Manifold - www.Fourby.co.uk

fourby.co.uk fourby.co.uk
Meantime and app 50 hours of work later, possibly more! I've polished my ports and done some work on my valves too.
I found a cheap air pencil di-grinder and a Dremel with Flexi extension extremely useful tools and worth every penny. Being a scotsman this is most important lol
IMG-20240327-WA0002.jpeg

The £15 air di-grinder is completely amazing, and was really the tool to finish some tiny difficult to reach parts like at the top of the swirl of the inlet ports, where the finish of the cast left much to be desired. I imagine the air will be flowing at it's fastest here. So rough casting imperfections causing turbulence would not be helpful.
PXL_20240330_130615769.MP.jpg
PXL_20240330_130619317.jpg
 
I forgot to mention, I was using a very small grinding stone on the pencil air die grinder, with wd 409 which stopped the stone clogging with Alu.
1712825271474.png

You can see all the ****e sticking oot better in this pic.
There is also minimal machining from the fitting of valve seat inserts, and the most basic transition from hardened steel to cast Alu.
I believe many new engines have more optimized castings and ports from the factory, but oor auld tractors have scope for improvement as they come.

The exhaust bowl behind the valve has some basic machining too, but again it's quite rudimentary, with lots of scope to improve the flow.
1712825733999.png

I find it really hard to get a good picture of shiny bits, but the finish in this picture is much smoother than it appears
1712826164123.png

Likewise, the inlet and exhaust ports
1712826237451.png
 
marjon said:
You are comparing Apples to Oranges and you know it.

Normally aspirated to Turbo, Totally different.

J
Click to expand...
Yes they are different, but intake design still matters and will still make a similar difference. Again there is loads and loads of info and vids out there proving this if you want to go and look. :) I'll try and dig one out later.
 
300bhp/ton said:
Yes they are different, but intake design still matters and will still make a similar difference. Again there is loads and loads of info and vids out there proving this if you want to go and look. :) I'll try and dig one out later.
Click to expand...

I am absolutely not taking anything away from what @Wagon Loon is doing, and it will help, will it be noticeable? If its only his labour then that's fine.


Don't waste your time digging stuff out. I don't need it. I understand tuning an engine.
If you want to discuss then start a thread.

But back to the original Q is it worth it on its own as a noticeable improvement without other stuff?

J
 
Peggy the farmy pick-up did seem a little quicker than I was expecting. Out accelerating a 2018 transit to 80 up a hill on the duel carriageway. I believe it has the same engine as the last Defenders, and they may have had some load, so it means nothing really.
I attributed this to her being the lightest Defender 300tdi, bar the military lightweight 90's.
An experienced head builder would have achieved all this in ten hours most likely. But although I used to work on new XJ6's in the seventies, at a garage were we specialised in tuning Jags to more than double their power. I'm Just learning what will help make my wee farmy truck a bit more drivable, and having some fun on the way. I'm retired so the day spent out in my workshop is a good day 😎
I modified the intake valves to reduce turbulence by tried and tested means. Swirl Polishing them behind the stem and because there is no fuel mixing happening, being direct injection.
The EGR has been removed previously which should things to stay clean on the intake side.
I took out the sharp edge at the bottom of the exhaust valves to reduce turbulence of escaping glasses wrapping round the edge
PXL_20240327_171737252.jpg
PXL_20240327_171744389.MP.jpg
PXL_20240406_175443067.jpg

It's quite subtle and not easy to see. But if you can feel a huge difference when you run your fingers over the path taken, it's so much smoother to the touch.
 
You must log in or register to reply here.

Similar threads

N
MG6 engine (non turbo) in 1.8 Freelander - inlet & exhaust manifold issues
Replies
9
Views
2K
niccage
N
K
What money should I be asking?
2
Replies
27
Views
4K
Karls
K
miktdish
Inlet manifold threads dead and revised.
Replies
5
Views
1K
payydg
payydg
Nardo90
200 TDI engine rebuilt and collected!!!!!!!!!!!!!!!! (plus back story, short version.)
Replies
14
Views
3K
Nardo90
Nardo90
Saltlick
Inlet port gunge cleaning - how the hell?!
Replies
4
Views
2K
Blackburn
Blackburn
Back
Top