V6 Exhaust now sorted....

[Stickyfinger]

New (changed) exhaust fitted. ZERO drone in car now and very comfortable at any speed.....sorted.

[Fake Concern]

Sounds great!

[Stickyfinger]

Tried to keep it OEM looking

[CitroJim]

Certainly sounded gorgeous when I heard it 'live' the other day Alasdair

[Stickyfinger]

Thanks Jim, next time your down we can take it out and you can see what it is like "in car"

[CitroJim]

Thanks Jim, next time your down we can take it out and you can see what it is like "in car"

That'll be magic Alasdair

I was particularly impressed with how they finished off the tailpipes... very smart indeed!

[Mandrake]

What exhaust did it have before - an old original system with the back box rotted away inside or a cheap 3rd party one ? (EG, Polish Ebay....)

My first V6 had an original exhaust system with a really bad drone/boom at 1500 rpm, presumably all the baffles in the back box were rotted away... I replaced it with one of the £80 Polish ones and the 1500rpm boom went away to be replaced with a 2500rpm drone!

On my current V6 the original factory exhaust was very quiet when I first got it until it burnt a hole through the clamp area at the front of the back box - limited funds again dictated that it would have to be a cheap £80 Polish Ebay job, and whilst some of the finishing wasn't brilliant and a couple of pipe angles had to be "adjusted" to get things to line up properly (thanks David ) once on it sounds absolutely fine - although it sounds slightly louder on the outside than the original OEM system it has a nice sound, and it's as quiet as a mouse inside the car...and no 2500rpm drone even though it appears to be the same design I fitted to the old V6...

[Stickyfinger]

Original OEM, which I have kept just in case things did not work out for this one and I had to swap back to the orginal.
It has some areas that would of needed attention on the back box which I think is caused by condensation . The middle box is perfect having had dry life without no salt, pipes are good as well.

I wanted better breathing and a little more "burble & rasp". It is about it all adding up to better response, K&N filter, throttle body, distribution manifold, exhaust ect.....started to strip the spare engine yesterday to work on the cylinder heads and plan up some Ss exhaust manifolds.

[Mandrake]

Original OEM, which I have kept just in case things did not work out for this one and I had to swap back to the orginal.
It has some areas that would of needed attention on the back box which I think is caused by condensation . The middle box is perfect having had dry life without no salt, pipes are good as well.

Where is the new system from ? Is it custom made ?

I wanted better breathing and a little more "burble & rasp". It is about it all adding up to better response, K&N filter, throttle body, distribution manifold, exhaust ect.....started to strip the spare engine yesterday to work on the cylinder heads and plan up some Ss exhaust manifolds.

Just an observation - if you've fitted a custom exhaust with better flow / less restriction than the OEM design, keep in mind that the ES9J4 is a speed/density (MAP) system which means that it is unable to detect and compensate for any increase in volumetric efficiency afforded by an improved exhaust flow, compared with a MAF system where the increased flow would be automatically detected and utilised, and the correct mixture maintained.

On a speed/density system an exhaust restriction will cause it to run too rich while conversely a better than normal (standard OEM) exhaust flow will cause it to run too lean because the MAP tables are all computed for the Volumetric Efficiency of the OEM exhaust... In short it will cause it to run leaner than normal and not utilise the benefit of increased flow, and at worst if you go too far it may actually run worse due to running far too lean.

(If you've had the misfortune to have the pipe between the cat and the centre silencer split and fall apart whilst driving as I have, you'll notice that the engine performance goes completely down the tubes when the exhaust pipe terminates just after the cat! Due in part to the engine now running really lean with much less exhaust restriction than normal...)

Luckily for you I have just the solution for you in my fuel pressure regulator thread... In all seriousness though, if you have done anything to increase exhaust or intake flow over OEM you really ought to lift the fuel pressure a little to make sure that you don't run too lean and that you actually get the benefit of the improved flow. The alternative is a custom ECU remap, but that is prohibitively expensive and not easy to come by on this engine. An hour swapping a fuel pressure regulator is so much cheaper, easier and easily reversible if you don't like the result.

[Stickyfinger]

Cheers for the info

I fitted a new Bosch regulator a few days after the exhaust which was custom made for the car.~
(Bosch 0280160562 Pressure Regulator)

[Mandrake]

3.5 bars though, or just the standard 3.0 ?

[Stickyfinger]

3.5 Bar, and I like the result

All the little things seem to be making a nice improvement to the response, not a clue on any/if increase in BHP but it seems to pull much better these days
(fitted new plugs as well)

I have an MOT at 3pm, I wonder if I will see any difference in the outputs.

[Mandrake]

Cool. Did you notice any change, or did you change the exhaust system at the same time without a chance to drive it in between ?

[Stickyfinger]

yes I did drive it before and after, much better pulling at low revs.....cannot really when flat out tell but she is running very well atm.

Very hard to tell as I keep changing little things ....but certainly not worse

[Mandrake]

3.5 Bar, and I like the result

All the little things seem to be making a nice improvement to the response, not a clue on any/if increase in BHP but it seems to pull much better these days
(fitted new plugs as well)

I have an MOT at 3pm, I wonder if I will see any difference in the outputs.

As long as your oxygen sensor is working properly the change in fuel pressure won't hurt your emissions test. My old V6 went through an emissions test with flying colours with its 3.5 bar regulator!

If you've done other jobs like spark plugs etc you may see an improvement over your last MOT as well.

And yes mine does seem to pull really well low down too. It was good before but is quite noticeably better since I changed the fuel pressure.