Smoother running Tdi engine

[Chicken Drumstick]

2 hours ago, Snagger said:

Because proper testing produces quantifiable data that undermines placebo effect and BS sales claims!

I know you are having a personal dig at me because you have some personal grudge against me. But there is no placebo effect. 
 

When I let someone else drive the vehicle. The first thing they said was it was running much smoother than any Tdi they’d driven. I’d said nothing at all to them prior. 

[Chicken Drumstick]

36 minutes ago, FridgeFreezer said:

Now, not to judge whether this thing is helping or hindering or doing nothing, but my 2p's worth;

It's fairly well known that humans are terrible at judging performance upgrades like this - often you can make changes that hurt performance but actually make the thing feel (or sound) "better" or sportier and people will be absolutely convinced it's made an improvement.

Loud exhausts are the classic, a lot of them hurt performance as many of them are just thrown together to look shiny and sound sporty and it's a huge factor in how drivers perceive the performance.

I've seen it 1st hand and done some moderately non-scientific experiments many moons ago working at a kart track - with 50+ identical karts all with computer timing transponders being driven almost constantly by a huge mix of drivers you could pick out particular karts that, due to age/wear/damage would be faster or slower than the fleet, but they were often the ones that subjectively felt the opposite.

The common example was karts with a cracked chassis felt faster because they hugged the corners better (flex!) but were demonstrably slower, while karts with a damaged exhaust felt faster because they were louder but actually ran slower.

Personally I can believe that a change to the induction system that softens the cacophony of clattering from under a 200TDi bonnet would make the vehicle feel a lot smoother and could result in a subtle driving style change that ends up being reflected on the GPS-dyno.

I haven’t been to the location to run the timing gear as per my earlier post. But I have done some GPS measurements. Top speed has increased by about 5% and on a fixed distance from a rolling start it is now trapping 78mph were previously it was only pulling about 70mph. 

[ThreePointFive]

19 minutes ago, Chicken Drumstick said:

I know you are having a personal dig at me because you have some personal grudge against me. But there is no placebo effect. 
 

When I let someone else drive the vehicle. The first thing they said was it was running much smoother than any Tdi they’d driven. I’d said nothing at all to them prior. 

I don't think anyone in the thread is having a dig at you. If anything Snagger is digging at the sellers of untested 'performance' equipment.

There's clearly a lot of skepticism around this product, the only/best way to prove what your seat is telling you is for the rolling road test. That said, no one is denying that the car may feel better and, if anything, that's more important than peak power on a day to day basis. If the car is appreciably smoother, then you're onto a winner - I think most people's objection is that these are sold on the basis of unsubstantiated performance claims.

If I have learnt anything about this lot it is that they are annoying, anal, highly knowledgable and usually right.

I'm just waiting for measurable data as I am really interested to see how the collective's engineering knowledge bears up against the numbers.

Now, if we were to measure before and after NVH.... well, there's a different thread.

[monkie]

I think this is an interesting thread to see people's thoughts on the subject. I don't think there are any personal attacks here. It's your Land Rover and if you like a modification plus think it drives better then great. I like to annoy purists by daring to have the white lettering facing the OUTSIDE of my tyres 

As an entirely separate point, I would be interested to see some data just out of idle curiosity. 

 

[geoffbeaumont]

Certainly no dig on my part - if you're happier with the vehicle post fitting it, then money well spent.

Just saying that if it does work as advertised then the manufacturer should be in a position to publish evidence of that - if they aren't, then they've no way to be sure they are advertising honestly, and also if they did test properly it's quite likely they'd be able to improve the product!

[Mo Murphy]

3 hours ago, monkie said:

I like to annoy purists by daring to have the white lettering facing the OUTSIDE of my tyres 

 

Dear God, Monkie, have you no shame ?

Mo

[monkie]

4 hours ago, Mo Murphy said:

Dear God, Monkie, have you no shame ?

Mo

Nope, none. 

[Snagger]

9 hours ago, Chicken Drumstick said:

I know you are having a personal dig at me because you have some personal grudge against me. But there is no placebo effect. 
 

When I let someone else drive the vehicle. The first thing they said was it was running much smoother than any Tdi they’d driven. I’d said nothing at all to them prior. 

No, I’m not.  There are a multitude of products in all fields, not just automotive, that rely on placebo effect, contrary to claims by their manufacturer, but their users swear by them.  Homeopathy and alternative medicine is a good example.  A lot of people swore how well the wire pyramid of their razor kept the blade sharp for longer.  The malpractice is everywhere, and I’m not having a pop at any single person over it.

For what it’s worth, a few people have told me that the fuel pump spacer ring you installed works well for smother engine running at higher rpm.  I can see how that works, and it was fitted by Bosch on similar pumps for other vehicles.  I have no reason to doubt that your engine may be smoother than before.  I just doubt it’s because of the manifold, but I’m not saying that is impossible, just that I doubt it.

[Jon W]

@Chicken Drumstick I am not into the engineering or science of which a lot of people are arguing, but am also sceptical about the improvement it can provide in term of power.

However  I do believe in what you are saying about improvement in engine smoothness. When I refined some of the pipe work and fitted a bitter intercooler into my 200tdi disco engined 90, apart from more power, it definitely felt better low down and smoother running. Yes supposedly more turbo lag, but I didn't find this either on this or my vw tdi which I had in a van and put loads more pipework and a silly big intercooler into, and again this smoothed the engine out.

The argument about air flow and having to change direction 90 degrees, being a smoother curve is probably better, as in the standard manifold it has enters the plenum and then goes 90 degrees anyway or hit the back of the engine if it reaches it. 

It would be good to see real world test figures as you say you are hoping to do. Also anything to smooth out a 200tdi in my eyes is a winner 

 

Jon 

 

[Nonimouse]

11 hours ago, Chicken Drumstick said:

You could say the same about bigger inter coolers. Or a Defender 200Tdi vs a 300Tdi (200 is further back with longer pipes to the IC). 
 

Im not sure anyone ever really complains about more lag in these circumstances. 
 

And I can attest, it doesn’t feel more laggy now. If anything less, but as it is smoother it does also pull better off boost too. 

I wonder if, like the removal of a centre box, the manifold allows the turbo to spool up sooner...  That is one of the most significant simple mods to a turbo diesel

[L19MUD]

11 hours ago, ThreePointFive said:

Now, if we were to measure before and after NVH.... well, there's a different thread.

I think this would be really interesting tbh

[Chicken Drumstick]

12 hours ago, ThreePointFive said:

Now, if we were to measure before and after NVH.... well, there's a different thread.

I have no idea how I could measure that. And I wasn't really expecting it either.

The only way I can describe it is, the Tdi is a lovely engine, but unrefined and gruff. You can almost feel the pulses as each cylinder fires. They just aren't smooth engines. Now the engine feels a lot more 'creamy' to rev, if you know what I mean. NVH in my vehicle is awful (It's a Series) in general. But you really can tell a huge difference on how the engine feels.

[Chicken Drumstick]

10 hours ago, geoffbeaumont said:

Just saying that if it does work as advertised then the manufacturer should be in a position to publish evidence of that - if they aren't, then they've no way to be sure they are advertising honestly, and also if they did test properly it's quite likely they'd be able to improve the product!

I agree, although in fairness. Fourby don't seem to be making any claims. Very little info on the item listing:

 

Tdi Twin Inlet Tuned Manifold.

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.

 

I can't see any claims of power or performance increase from them.

[Chicken Drumstick]

5 hours ago, Snagger said:

 

For what it’s worth, a few people have told me that the fuel pump spacer ring you installed works well for smother engine running at higher rpm.  I can see how that works, and it was fitted by Bosch on similar pumps for other vehicles.  I have no reason to doubt that your engine may be smoother than before.  I just doubt it’s because of the manifold, but I’m not saying that is impossible, just that I doubt it.

Boost ring and manifold weren't fitted at the same time. About 8 weeks or so inbetween.

[Nonimouse]

This is a nice simple calculator for air flow https://www.widman.biz/English/Calculators/CFM.html

This is why I wanted to know how much more flow was claimed. Then you could calculate how much more fuel could be thrown in.

Traditionally this is done with a bigger bore air induction system - all the way from the inlet to the manifold. A diesel manifold is designed with swirl integrated, to improve fuel/air mix - so is not polished or smooth - whereas polishing the exhaust side helps ... Porting allows more flow, as does matching component faces (blue printing) and finally more forced induction (bigger or twin turbo set up)

NVH can be improved by something as simple as using higher calorific value fuel. So premium or ultra grades (also good for injector longevity) or additives (like Millers) which improve calorific value) or alternative fuels, such as pure rapeseed oil (again higher calorific value).

Injectors are a 100k service item on a 200 0r 300. 200 injector heads are no longer available, but a 300 head fits, will provide the same pressures and the same spray pattern (no more) and are available from Bosche.

 

 

[missingsid]

Tdi Twin Inlet Tuned Manifold.

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

 

Now I am confused, they chop off and blank the original pipe from the intercooler and add two new ones to the side. Where/how do they tune and balance the flow??

If they grind out the inlet ports that won't do anything as the cylinder head ports will not match?

 

 

[Bowie69]

They just make the two ports on the manifold flow evenly.

[citizen kane]

I figure you are getting around a 16% increase in power to get a 5% increase in top speed, if correct that's very cheap horsepower.

[Ex Member]

8 minutes ago, citizen kane said:

I figure you are getting around a 16% increase in power to get a 5% increase in top speed, if correct that's very cheap horsepower.

You misunderstood what he wrote.  That was not his top speed.  That was his speed after accelerating a fixed, known distance.

As far as the math.  78/70 = 1.11 ==> 11%.   Power increase if this was actually top speed is (78/70)^3 = 1.38.  38% increase in power.  If 70 had been his top speed, his engine would have been broken.  A standard Defender 300TDI should happily make 85 which requires 80% more power than 70.

[Chicken Drumstick]

Thanks Red90. Yes the 78mph vs 70 was just a rolling start from point x to point y on a level gradient and set distance. My 4.6 p38 does approx 84mph over this distance. This is comparing pre boost ring & manifold.  I didn’t gps with just the boost ring, but the speedo would have equates to 74-75mph. So still a speed increase with just the manifold. 
 

As for vmax I GPS clocked it at 95.4mph. Which is circa 5% increase (this is boost ring and manifold). 

[citizen kane]

32 minutes ago, Red90 said:

You misunderstood what he wrote.  That was not his top speed.  That was his speed after accelerating a fixed, known distance.

As far as the math.  78/70 = 1.11 ==> 11%.   Power increase if this was actually top speed is (78/70)^3 = 1.38.  38% increase in power.  If 70 had been his top speed, his engine would have been broken.  A standard Defender 300TDI should happily make 85 which requires 80% more power than 70.

I've not misunderstood, I wouldn't have a clue about how to calculate the power increase due to the improved acceleration, the claim was a 5% increase in top speed and as you point out that's a cubic rule so it does equate to around 16%

[Nonimouse]

You can get 15% with the right atmospheric conditions - according to Powerhouse DD

[pat_pending]

I'm surprised these manifolds haven't appeared on here before, they've been around a few years.

I had a short conversation with the bloke that sells/makes them once, and he was talking utter garbage regarding how they worked.

They are going to do nothing for performance.

However, it's interesting regarding the "feeling smoother" part, as altering the shape of the manifold will have an effect on felt/heard intake resonance.

That can certainly determine how an engine feels.

 

[Snagger]

9 hours ago, Nonimouse said:

You can get 15% with the right atmospheric conditions - according to Powerhouse DD

In this neck of the woods, my tyre pressure can go from 32 psi when I first get into the car to 38psi during a moderate drive on the motorway in the early afternoon.  That will have a big effect.  Then, as you said, the atmospheric conditions make a big difference to engine performance and a measurable effect on drag on the vehicle.  Add in different transmission temperatures affecting oil viscosities and bearing preloads, there is an awful lot that can affect driving tests on different dates or even just different times of the same day.

[Daan]

Interestingly, international also had a go at the manifold when they upgraded the tdi to 2.8L: