Going back to Standard CDti Air Duct

[bl52krz]

Originally Posted by rovexCDTi

Again theory, but where is the evidence that this actually happens? why does a slightly freer flow of air before the aperture the MAFF sits in reduce air flow? The engine is still demanding the same volume of air through the same aperture. The intercooler O rings are a totally different story and irrelevant to this discussion.

If it feels better I couldn't care less if its 'correct' or not.

It "feels better". That is called the "placebo effect". The argument can only be proven, OR NOT, by readings that are taken by the MAF.

[BigRuss]

Originally Posted by rovexCDTi

Again theory, but where is the evidence that this actually happens? why does a slightly freer flow of air before the aperture the MAFF sits in reduce air flow? The engine is still demanding the same volume of air through the same aperture. The intercooler O rings are a totally different story and irrelevant to this discussion.

If it feels better I couldn't care less if its 'correct' or not.

Not theory at all but years of practical experience

I don't say these things for fun it's because they're correct and for the benefit of members on here to help them to avoid the pitfalls of some modifications.

The O rings are of relevance as they can have a dramatic effect on the airflow just as altering the intake/ air filter it alters the fueling just the same why do you think blown o rings cause excessive black smoke it's because the airflow is too high as seen by the maf thus causing too much fuel to be injected.

Russ

[wesley]

Originally Posted by rovexCDTi

Ive put it under the nearside headlight, back a little bit, seems to pick up cool enough air, and is safe from water splash.

thank you for your help.

[rovexCDTi]

Black smoke isnt a placebo, and ive been driving long enough and im cynical enough to be able to tell the difference. I will take readings if you like. Without those figures its meaningless to argue.

In terms of physics if the intake is enlarged you wont reduce velocity if the measuring points aperture is unchanged, however you will reduce lag in the time it takes the pressure to equalise. The pressure is only lower before the MAF, not over the MAF.

The only question is whether the reduced pressure effects the airs inertia, but in my set up it wont because I havent changed the size of the airbox or the airbox intakes size.

At the end of the day, if i want to be able to use the Synergy on '10' and not have black smoke I HAVE to have my modified intake, especially in this heat and at low speed.

[Ross R75]

Originally Posted by rovexCDTi

Ok on the first point, even if my results arent agreeing in practice, but the second point is mute since you aren't effecting the size of the 'straw' because you havent changed the size of the aperture the MAFF sits in. Everything from the air box onwards is the same.

If you enlarge everything I agree with you, but you arent.

For me the air intake was never about ultimate power, it was about response and temperature. It feels more responsive and the temp is lower (very slightly), according to whats reported by Torque (on my phone)

You don't need to change the size of the aperture the MAF probe sits in, because the probe sits at the entrance to the MAF housing. The intake air is still accelerating at the point of crossing the heated wire. The turbulence and oscillation of the intake air is also completely different because of the alteration to the intake ducting.

Nobody here is being deliberately argumentative with you, they've just seen it all before, over and over again. Russ and Brian are very helpful and trust me, they probably know more about the engine mapping on the M47R and the consequences of alterations to anything affecting that mapping than anybody at MG Rover ever did.

[rovexCDTi]

Originally Posted by BigRuss

Not theory at all but years of practical experience

I don't say these things for fun it's because they're correct and for the benefit of members on here to help them to avoid the pitfalls of some modifications.

The O rings are of relevance as they can have a dramatic effect on the airflow just as altering the intake/ air filter it alters the fueling just the same why do you think blown o rings cause excessive black smoke it's because the airflow is too high as seen by the maf thus causing too much fuel to be injected.

Russ

Yeah but its for a different reason. The turbo is just blowing its pressure out and therefore spinning faster to try to reach the correct boost and sucking in more air that never gets to the engine. This fools the MAF because the air never gets to the cylinders.

You still havet explained why the velocity would be lower across the same aperture just because of a slightly larger intake upstream.

Your straw analogy doesn't work because you aren't enlarging the entire straw. What im doing is widening the bottom of the straw and leaving the rest, including the part with the MAF in it, the same.

What you are saying is that if i made the bottom of the straw narrower the fluid would travel up the straw faster, thats just not the case. It would only travel through the opening faster.

[Ross R75]

Originally Posted by rovexCDTi

At the end of the day, if i want to be able to use the Synergy on '10' and not have black smoke I HAVE to have my modified intake, especially in this heat and at low speed.

The problem doesn't lie with the air intake, it lies with the crude and expensive resistor you've attached to your engine. Your fueling is all over the place with the Synergy fitted. The difference in delivery, increase in power and reduction in smoke with the 160bhp remap over the Synergy has to be experienced to be believed.

[rovexCDTi]

Thats fine, and I did say I believe that the 160 map is better, but thats still not relevant to those of us who have a synergy.

The issue I have is that Ron was criticised for suggesting the intake be modified, but it works for his set up which was around long before the 160 was available, so was the only decent option we had at the time.

Your 160 map is designed to work with the standard intake, if all the intake mod does is affect the MAF readings then it could equality be made to work with a modified intake. Of course i would fully understand why you wouldn't do this.

Its been claimed that the modded intake reduces flow, it doesn't, if your readings suggest the MAF think is it does then thats a different thing entirely.

Trust me if i wasn't so far away id have the 160 remap like a shot, i still have my Bosch MAF.

[marinabrian]

Originally Posted by rovexCDTi

Thats fine, and I did say I believe that the 160 map is better, but thats still not relevant to those of us who have a synergy.

The issue I have is that Ron was criticised for suggesting the intake be modified, but it works for his set up which was around long before the 160 was available, so was the only decent option we had at the time.

Your 160 map is designed to work with the standard intake, if all the intake mod does is affect the MAF readings then it could equality be made to work with a modified intake. Of course i would fully understand why you wouldn't do this.

Its been claimed that the modded intake reduces flow, it doesn't, if your readings suggest the MAF think is it does then thats a different thing entirely.

Trust me if i wasn't so far away id have the 160 remap like a shot, i still have my Bosch MAF.

Modifying the intake serves to bypass the water shedder... period, it does not increase the volume of air by any appreciable amount.

This is a known cause of premature MAF failure, as an aside recommended by the person who has vested interests in selling replacement MAF sensors.
I don't sell MAF sensors, I can only speak from experience in taking real time readings from MAF sensors which have been destroyed by this particular modification.
If I were feeling particularly generous, I would say that a Pierburg MAF was a drop in replacement, however even with MAF signal amplification the result is an output which is far to high at idle and woefully inadequate at 3000 RPM, and as one owner recently found out, was no more robust in terms of water contamination.

Of course this is preferable to a completely out of spec Bosch MAF, however with the price of a genuine Bosch MAF less than half of the original £250, there is no need to compromise any more.

In addition, I have now come across no less than seven cars with HP pump failure, in each case the car was fitted with an HP sensor sensor attenuator tuning module, with the setting on "10".

The DDE4 ECM is a very complex instrument that relies upon the correct data being fed from it's various sensors, and the corruption of a signal from a sensor which is reporting an common rail pressure of 20,000 P.S.I. where the actual pressure is in the region of 24,000 P.S.I. is asking for trouble.

I now await an angry retort from the man who has sold a "million quids worth" of these tuning boxes, but unlike that person, I only care about what is right for our cars, and not simply making money from people.

Brian

[rovexCDTi]

I cant and wont speak for the effect of the synergy on the engine, but there is no doubt changing the intake has a positive effect on a synergy equipped car in terms of response, and that was all I was ever arguing.

So where is the nearest 160 mapper to Exeter?