Omega Owners Forum

Please login or register.

Login with username, password and session length
Advanced search  

News:

Search the maintenance guides for answers to 99.999% of Omega questions

Pages: 1 2 3 [All]   Go Down

Author Topic: exhaust v6  (Read 4339 times)

0 Members and 1 Guest are viewing this topic.

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
exhaust v6
« on: 06 May 2016, 09:24:56 »

What is the standard pipe bore for a v6 omega exhaust..

Thinking of having a stainless one made my powerflow for my elite..
Will tell them...

Want it quiet like stock...
Twin angled tips like stock...

Couple things unsure off though

Do you think worth having a x pipe in system to balance flow..
Mandrel or crushed bend or is there nothing init on road use really

And also seen as mine a 3.2 thinking of deleteing pre cats and swapping cata for sports cat recomended or not ??
Logged

biggriffin

  • Omega Lord
  • *******
  • Offline Offline
  • huntingdon, Hoof'land
  • Posts: 8097
    • Vectra in a posh frock.
    • View Profile
Re: exhaust v6
« Reply #1 on: 06 May 2016, 10:00:32 »

If fitting a stainless system, best off getting the full system from demon twerks, it's a jetex, system looks identical to standard, flows better, cost bit more than a "bespoke"

The problem with the so called bespoke systems, they, use a join, and change it to a single box system,
Two centre boxes replaced, by 1, to make the over axle bend easier, and one pipe, some also cut the flanges off,, and weld the new system on to the downpipes, or make the new system slip jointed, on to downpipes.
Logged
Hoof'land storeman.

andrewrobuk

  • Newbie
  • *
  • Offline Offline
  • Gender: Male
  • Sunderland
  • Posts: 20
    • '00 3.0 MV6 Estate
    • View Profile
Re: exhaust v6
« Reply #2 on: 06 May 2016, 10:42:42 »

I would recommend the Jetex system. Probably is more expensive but to me it seemed better quality and more pipe work than the custom Powerflow exhaust that I took off mine.
The Powerflow came with the car and couldn't have been on that long really. Started to get a terrible noise which was I guess a baffle plate in the one centre box that was there instead of the two separate.
Not sure if the cause of the plate rattling was down to the two pipes joining after the cats and then into one box and one pipe thereafter, but it must have been more restrictive for gases.
The mess that the cats flanges were in after removing the Powerflow, I had to get new flanges welded on, but it was never right and replaced the cats not too long after that
Logged

andrewrobuk

  • Newbie
  • *
  • Offline Offline
  • Gender: Male
  • Sunderland
  • Posts: 20
    • '00 3.0 MV6 Estate
    • View Profile
Re: exhaust v6
« Reply #3 on: 06 May 2016, 10:46:26 »

Also, not sure of the standard bore but the Jetex is 2.5inch all the way through. Sound is good too. Fairly quite on idle, low down rumble on accelerating. It doesn't sound cheap if you get me
Logged

YZ250

  • Omega Baron
  • ******
  • Offline Offline
  • Gender: Male
  • Oxford/Bucks border
  • Posts: 2813
    • Black 3.2 Elite Estate
    • View Profile
Re: exhaust v6
« Reply #4 on: 06 May 2016, 12:03:13 »

I agree with all of the above with regards to the bespoke systems. Many years ago I had quotes from the likes of Powerflow and Longlife for my 3.2 but you need to question what you are getting as Powerflow would have been quite happy to chop the flanges off and weld it straight to the downpipes. Longlife were going to fabricate a single pipe system, not the dual pipes, so I didn't like that either. With the Jetex system, apart from the bigger bore, it replicates the original system. It was a perfect fit and really easy to do yourself, assuming the flange bolts come off easily. Been on mine for around seven years and not given me any problems so far touchwood.  :y
I only went down the stainless route as I needed a new exhaust and thought it would eliminate any future zorst worries but as I say, that was years ago so I've had my money's worth out of it now.  :y
If you do go bespoke, make sure that they are aware of your wishes before they start to rip the old one off.  :y
Logged
My fun car is a 2019 Bmw F32 430d M Sport with indicators.

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #5 on: 06 May 2016, 12:22:34 »

No they dont

The quote is for a copy of my systen two pipes front to back box .. two centre silencers
And a rear backbox.

Looked at jetex before bit tips just look stupid 80mm and round ... unfortunetely no offer of other tips..

I know what your saying about longlife and powerflow as there a franchise some are of poor quality i got stung by longlife on a old car but when i had misses decat made at a different dealer they did a spot on and tig welded joints were beautiful..

With regards to flexi joint etc they will do what u ask.. mine will be flexi jointed twin centew boxed possibly with xpipe to balance flow between banks..


Also if yours sounded awful you should have gone back you get lifetime guaratee and faults they fix it...


Im more after as i asked in first quotes... is a xpipe recomended and bore size of std system...
And does anyone have any recomendation of removing pre cats and fitting sports cats is it a
Worthwhile mod...

Not really asking about brand or where to buy from cheers though


If fitting a stainless system, best off getting the full system from demon twerks, it's a jetex, system looks identical to standard, flows better, cost bit more than a "bespoke"

The problem with the so called bespoke systems, they, use a join, and change it to a single box system,
Two centre boxes replaced, by 1, to make the over axle bend easier, and one pipe, some also cut the flanges off,, and weld the new system on to the downpipes, or make the new system slip jointed, on to downpipes.
Logged

Lazydocker

  • Omega Queen
  • ********
  • Offline Offline
  • Gender: Male
  • Woodbridge, Suffolk
  • Posts: 18838
  • Constantly Bullied by a certain Admin
    • View Profile
Re: exhaust v6
« Reply #6 on: 06 May 2016, 12:43:25 »

No they dont

The quote is for a copy of my systen two pipes front to back box .. two centre silencers
And a rear backbox.

Looked at jetex before bit tips just look stupid 80mm and round ... unfortunetely no offer of other tips..

I know what your saying about longlife and powerflow as there a franchise some are of poor quality i got stung by longlife on a old car but when i had misses decat made at a different dealer they did a spot on and tig welded joints were beautiful..

With regards to flexi joint etc they will do what u ask.. mine will be flexi jointed twin centew boxed possibly with xpipe to balance flow between banks..


Also if yours sounded awful you should have gone back you get lifetime guaratee and faults they fix it...


Im more after as i asked in first quotes... is a xpipe recomended and bore size of std system...
And does anyone have any recomendation of removing pre cats and fitting sports cats is it a
Worthwhile mod...

Not really asking about brand or where to buy from cheers though


If fitting a stainless system, best off getting the full system from demon twerks, it's a jetex, system looks identical to standard, flows better, cost bit more than a "bespoke"

The problem with the so called bespoke systems, they, use a join, and change it to a single box system,
Two centre boxes replaced, by 1, to make the over axle bend easier, and one pipe, some also cut the flanges off,, and weld the new system on to the downpipes, or make the new system slip jointed, on to downpipes.

To answer your initial question. The original exhaust doesn't have a cross pipe so it isn't needed. As for sports cats... Mixed experiences I'm afraid but I have none on an Omega.

As for the other comments... Just the experiences of people here. I've only ever seen stainless systems with single pipes, including the one on my other Omega ;)
Logged
Whatever it is... I didn't do it

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #7 on: 06 May 2016, 13:00:19 »

Again


Im not getting or have i mentioned im getting a single pipe system
.. getting a copy of std system twin pipe front to back

With regards to x pipe there suposed to encourage scavaging of exhaust gases and allow tone and decibel reading of exhaust to be altered... jist because it doesnt come with it doesnt mean it needed...

How does yours run with no cats is it better ??


No they dont

The quote is for a copy of my systen two pipes front to back box .. two centre silencers
And a rear backbox.

Looked at jetex before bit tips just look stupid 80mm and round ... unfortunetely no offer of other tips..

I know what your saying about longlife and powerflow as there a franchise some are of poor quality i got stung by longlife on a old car but when i had misses decat made at a different dealer they did a spot on and tig welded joints were beautiful..

With regards to flexi joint etc they will do what u ask.. mine will be flexi jointed twin centew boxed possibly with xpipe to balance flow between banks..


Also if yours sounded awful you should have gone back you get lifetime guaratee and faults they fix it...


Im more after as i asked in first quotes... is a xpipe recomended and bore size of std system...
And does anyone have any recomendation of removing pre cats and fitting sports cats is it a
Worthwhile mod...

Not really asking about brand or where to buy from cheers though


If fitting a stainless system, best off getting the full system from demon twerks, it's a jetex, system looks identical to standard, flows better, cost bit more than a "bespoke"

The problem with the so called bespoke systems, they, use a join, and change it to a single box system,
Two centre boxes replaced, by 1, to make the over axle bend easier, and one pipe, some also cut the flanges off,, and weld the new system on to the downpipes, or make the new system slip jointed, on to downpipes.

To answer your initial question. The original exhaust doesn't have a cross pipe so it isn't needed. As for sports cats... Mixed experiences I'm afraid but I have none on an Omega.

As for the other comments... Just the experiences of people here. I've only ever seen stainless systems with single pipes, including the one on my other Omega ;)
Logged

Kevin Wood

  • Global Moderator
  • *****
  • Offline Offline
  • Gender: Male
  • Alton, Hampshire
  • Posts: 35381
    • 3.2 MV6 (LPG), Westfield
    • View Profile
Re: exhaust v6
« Reply #8 on: 06 May 2016, 13:59:43 »

I have yet to hear a stainless system that isn't unbearably noisy. A bloke with stainless pipes and a welder is not going to fabricate a system that is as refined as the OEM exhaust. Full stop. He won't double wall the silencers, pack them properly with wadding or calculate their dimensions to stop resonances. If refinement is important to you, don't do it!

Make sure you do clearly specify twin pipes bolting to the original cat flanges because, as said, with 90% of fabricated systems we've seen they can't be arsed to keep the flanges and will cut them off and weld to the cats, which is unhelpful if you need to replace a cat. I don't doubt what you've been told, but plenty have come away and found that's what they've ended up with!

The only advantage I can see with a stainless system is lifetime, and with Omegas "getting on a  bit", you have to ask yourself if there's enough life in any Omega to make it worthwhile.

A decent aftermarket exhaust will offer good refinement, last for 4 years or more and cost 100. You can fit whatever tailpipe trim you want to it and your insurance company won't load your premium for having a modification. No-brainer.
Logged
Tech2 services currently available. See TheBoy's price list: http://theboy.omegaowners.com/

Kevin Wood

  • Global Moderator
  • *****
  • Offline Offline
  • Gender: Male
  • Alton, Hampshire
  • Posts: 35381
    • 3.2 MV6 (LPG), Westfield
    • View Profile
Re: exhaust v6
« Reply #9 on: 06 May 2016, 14:02:08 »

Oh, and unless you can do the calculations on where to locate it, a cross pipe will make no odds. I suspect it'd have to be very close to, if not before, the cats to have any impact on performance, and I think the firing order of the V6 would make them redundant anyway (they are useful on square plane V8s, if memory serves).
Logged
Tech2 services currently available. See TheBoy's price list: http://theboy.omegaowners.com/

Lazydocker

  • Omega Queen
  • ********
  • Offline Offline
  • Gender: Male
  • Woodbridge, Suffolk
  • Posts: 18838
  • Constantly Bullied by a certain Admin
    • View Profile
Re: exhaust v6
« Reply #10 on: 06 May 2016, 14:12:13 »

Again


Im not getting or have i mentioned im getting a single pipe system
.. getting a copy of std system twin pipe front to back

With regards to x pipe there suposed to encourage scavaging of exhaust gases and allow tone and decibel reading of exhaust to be altered... jist because it doesnt come with it doesnt mean it needed...

How does yours run with no cats is it better ??


No they dont

The quote is for a copy of my systen two pipes front to back box .. two centre silencers
And a rear backbox.

Looked at jetex before bit tips just look stupid 80mm and round ... unfortunetely no offer of other tips..

I know what your saying about longlife and powerflow as there a franchise some are of poor quality i got stung by longlife on a old car but when i had misses decat made at a different dealer they did a spot on and tig welded joints were beautiful..

With regards to flexi joint etc they will do what u ask.. mine will be flexi jointed twin centew boxed possibly with xpipe to balance flow between banks..


Also if yours sounded awful you should have gone back you get lifetime guaratee and faults they fix it...


Im more after as i asked in first quotes... is a xpipe recomended and bore size of std system...
And does anyone have any recomendation of removing pre cats and fitting sports cats is it a
Worthwhile mod...

Not really asking about brand or where to buy from cheers though


If fitting a stainless system, best off getting the full system from demon twerks, it's a jetex, system looks identical to standard, flows better, cost bit more than a "bespoke"

The problem with the so called bespoke systems, they, use a join, and change it to a single box system,
Two centre boxes replaced, by 1, to make the over axle bend easier, and one pipe, some also cut the flanges off,, and weld the new system on to the downpipes, or make the new system slip jointed, on to downpipes.

To answer your initial question. The original exhaust doesn't have a cross pipe so it isn't needed. As for sports cats... Mixed experiences I'm afraid but I have none on an Omega.

As for the other comments... Just the experiences of people here. I've only ever seen stainless systems with single pipes, including the one on my other Omega ;)

Don't know... I don't have any experiences on an Omega ;)

As for the cross pipe, I'm confused... You say one minute you want to fit a direct replacement, then talk about altering it for tone etc.... ::)

As for the Stainless... The only system I have experienced with no negative impact is the Jetex one. Every other system I've experienced has had an impact on performance.

At the end of the day, it's your car. People have given you advice and you can take on what you like.
Logged
Whatever it is... I didn't do it

YZ250

  • Omega Baron
  • ******
  • Offline Offline
  • Gender: Male
  • Oxford/Bucks border
  • Posts: 2813
    • Black 3.2 Elite Estate
    • View Profile
Re: exhaust v6
« Reply #11 on: 06 May 2016, 15:24:53 »

...................................
Make sure you do clearly specify twin pipes bolting to the original cat flanges because, as said, with 90% of fabricated systems we've seen they can't be arsed to keep the flanges and will cut them off and weld to the cats, which is unhelpful if you need to replace a cat. I don't doubt what you've been told, but plenty have come away and found that's what they've ended up with!
..........................

My point exactly.  :y  I was told what I wanted to hear but come the day they tried to persuade me otherwise, hence making it clear of what you want with no deviations. It was intended to be helpful and to save the OP picking his car up and being disappointed.

I'll admit that I missed the purpose of the original post and got side-tracked by stainless systems, so it may be better if some of the guys with Powerflow systems chipped in with their views as they have the experience of them.  :-\ 
As the Jetex system has been ruled out I won't bother mentioning that the Jetex Sports Cats downpipe bolts straight on to the car to make a complete system, or my opinion of it.   ;) :-X

No flexi joint on V6 downpipes by the way, just a simple flange to flange with steel ring between, so they will need to fabricate the flanges and dress the pipes or cut them off your old exhaust and weld them to the new pipe. They did the latter to my sons two vehicles.  ::)
Anyway, point made so bailing out.
Logged
My fun car is a 2019 Bmw F32 430d M Sport with indicators.

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #12 on: 06 May 2016, 16:13:53 »

Ive not seen nor is it listed on jetex site they do a sports cat downpipe..

If they do that be fab..

I completely know and understand it wont be as quiet as a mild steel system i jave stainles on all my cars
But you can get loud or quiet ones...

Yes i stated i want it to be a copy of std system and do in sense of two middle boxes and a rear silencer. But i was tempted by a x pipe to balance flow from bank to bank when its firing plus x pipes allow a decibel reduction due to the noises cancelling each other other out going through x pipe...

It would be after cat xpipe due to cooling of exhaust gas u dont want it mega hot


Im after releasing a bit of power hence were all this coming from and my omega i see me keeping it at least 5 years if not longer spot on car....


My plan was fit some 3.0 downpipes with sports cats welded in place of std cat
( lost pre cats and gained aports cats plus flow of earlier downpipes better due to shape)

Std bore mandrel bent cat back stainless system like std but with x pipe in it

Then have it mapped my motorsport developments

Any one got any advice?? Oh and anyone know other places to have omega mapped
Logged

pauls

  • Omega Baron
  • ******
  • Offline Offline
  • Gender: Male
  • By the sea minehead
  • Posts: 2066
    • Bmw x3
    • View Profile
Re: exhaust v6
« Reply #13 on: 06 May 2016, 16:14:46 »

Just down at profusion here at heathrow. At the moment just getting a stainless back box fitted. I was talking to the chap a full cat back system using magnaflow. He said he wouldnt go the route of 2 into 1 but would fit a crossover then bring them both into back box.
 After taking my back of he started the car and rev'd it.(what a lovely sound). Idea behind this was to get a sound level so we could decide what size rear box to put on. It now sound nice without any low down drone :y
Logged
..

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #14 on: 06 May 2016, 16:49:11 »


Spot on bud. .. yes a crossover is a xpipe what im on about recomended on twin bank engines to balance it out
Be good if u got a magnaflow system front ti back ...

Pics and videos would be awesome hahau



Just down at profusion here at heathrow. At the moment just getting a stainless back box fitted. I was talking to the chap a full cat back system using magnaflow. He said he wouldnt go the route of 2 into 1 but would fit a crossover then bring them both into back box.
 After taking my back of he started the car and rev'd it.(what a lovely sound). Idea behind this was to get a sound level so we could decide what size rear box to put on. It now sound nice without any low down drone :y
Logged

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #15 on: 07 May 2016, 07:15:06 »

Think im going to start small and see the improvements or lack off..

going to have new downpipes made with sports cats but leave the nice quiet system in place as condition is completely ok at moment.
complete full service
gearbox update via tech 2 (still cant find anyone local to liverpool)
remove excess pipe in airbox from bottom
and maybe get all injectors refurbed
Logged

tigers_gonads

  • Moaning Haddock Head
  • *
  • Offline Offline
  • Gender: Male
  • Kinston Upon Hull
  • Posts: 8368
    • 02 Mv6 Estate (lpg'd)
    • View Profile
Re: exhaust v6
« Reply #16 on: 07 May 2016, 19:31:51 »

Think im going to start small and see the improvements or lack off..

going to have new downpipes made with sports cats but leave the nice quiet system in place as condition is completely ok at moment.
complete full service
gearbox update via tech 2 (still cant find anyone local to liverpool)
remove excess pipe in airbox from bottom
and maybe get all injectors refurbed



Which v6 have you got fitted ?
Logged
Please note, 95% of my posts are piss take or banter and should always be taken as so.

Please feel free to give it back in the same spirit.

tigers_gonads

  • Moaning Haddock Head
  • *
  • Offline Offline
  • Gender: Male
  • Kinston Upon Hull
  • Posts: 8368
    • 02 Mv6 Estate (lpg'd)
    • View Profile
Re: exhaust v6
« Reply #17 on: 07 May 2016, 19:57:03 »

Think im going to start small and see the improvements or lack off..

going to have new downpipes made with sports cats but leave the nice quiet system in place as condition is completely ok at moment.
complete full service
gearbox update via tech 2 (still cant find anyone local to liverpool)
remove excess pipe in airbox from bottom
and maybe get all injectors refurbed



Which v6 have you got fitted ?



Okay, now i've read the thread in full  ::)

Save your money and don't bother with sports cats  ;)
Get your hands on a pair of 2.5 / 3ltr cats, weld a pair of lambda bosses in to accommodate the extra sensors of the DBW engines and fit them to a new, standard cat back system  :y :y
Logged
Please note, 95% of my posts are piss take or banter and should always be taken as so.

Please feel free to give it back in the same spirit.

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #18 on: 07 May 2016, 20:34:41 »

Surely sport cats gonna be a lot better than two std cats ??

And to get good std cats probs cost just as much??

My original plan was to just fit 3.0 downpipes and move lambda but i thought for a decent price i can have atainless downpipes mandrel bend with two magnaflow 200cell sports cats in them.. why would this not be better??
Logged

tigers_gonads

  • Moaning Haddock Head
  • *
  • Offline Offline
  • Gender: Male
  • Kinston Upon Hull
  • Posts: 8368
    • 02 Mv6 Estate (lpg'd)
    • View Profile
Re: exhaust v6
« Reply #19 on: 07 May 2016, 21:27:18 »

Surely sport cats gonna be a lot better than two std cats ??

And to get good std cats probs cost just as much??

My original plan was to just fit 3.0 downpipes and move lambda but i thought for a decent price i can have atainless downpipes mandrel bend with two magnaflow 200cell sports cats in them.. why would this not be better??



I'm not really an expert in the dynamics of these engines but my opinions are those of a bloke who has owned both the 3lt and the 3.2  :)

Tuning wise, without forced induction (turbo or supercharging) there is not a lot more power to be gained but you can make them a little more driveable .

I personally prefer the feel of the 3ltr engine but if it did have a problem, it was with the downpipes which was cast not tubular and definitely was a choke point with the exhaust gasses.

The DBW engines cured this with tubular manifolds which are iirc good for much more then the 210 bhp ish that the 3.2 will kick out even on a good day so imho, i'd leave the standard 3.2 manifolds alone  :y

If you look at the physical difference between the 3ltr and 3.2 cats, you will see that the 3lt one is quite a bit larger then 3.2 one and is constructed must better so not only do they breath better but also last much longer too hence some lads on here (including myself) have modified the old cats to take both lambda sensors once the DBW pre cats start to fail and fitted them to our DBW engines ;)
I can confirm that it does make it a little more driveable  :)

Right, the DBW engines bad bits ...........
To get the DBW engine threw the yanks market emission tests, they have to choke it up with the precat and also reduce the compression  :(
If you remove the 3.2 heads and fit a pair of heads off a 2.6 c/w the 3.2 valves and do a little porting in the inlet manifold area, not only will you raise the compression back upto around the 3ltr but you will also have more torque due to the extra capacity and greater drivability of the larger and more solid cats  :y

I understand what you mean about the aftermarket sports cats but with the 3ltr cats been so durable, it isn't really a problem to use a pair off a scrapper and with the sensor bosses fitted, I would think it would be better in the long run  :)

Exhausts .........

I would say that the standard size one would be more then good enough for the amount of gas that the 3.2 will kick out.
Fitting a nice clean new cat back system will cost you about 100 quid so unless you really want to spend money on a stainless or to change the tone then i'd go down that route  :y
Also bare in mine that these engines do need a little back pressure to give maximum output and tinkering too far from the original setup will probably loose you some lower end torque which is the last thing you want on a 2 ton car  ;)
   
Logged
Please note, 95% of my posts are piss take or banter and should always be taken as so.

Please feel free to give it back in the same spirit.

YZ250

  • Omega Baron
  • ******
  • Offline Offline
  • Gender: Male
  • Oxford/Bucks border
  • Posts: 2813
    • Black 3.2 Elite Estate
    • View Profile
Re: exhaust v6
« Reply #20 on: 08 May 2016, 09:59:56 »

Surely sport cats gonna be a lot better than two std cats ??
...............

Just something to be aware of, if your car was registered after 1st March 2001 the cats fitted to it must be type approved.
Boring info I agree, but not many sports cats are type approved and some are even stamped to make this clear.  :y
Logged
My fun car is a 2019 Bmw F32 430d M Sport with indicators.

TheBoy

  • Administrator
  • *********
  • Offline Offline
  • Gender: Male
  • Brackley, Northants
  • Posts: 99558
  • Millennium Man
    • The missus mad
    • View Profile
Re: exhaust v6
« Reply #21 on: 08 May 2016, 10:30:35 »

Lets take a step back, and ask the OP what he is trying to achieve, rather than 2nd guess :)

If it about durability and refinement, a known good (ETS or Eternal) will always be the most cost effective and refined option.

If its because itz well wicked to have stainless, coz itz where itz at, then its a rather pointless conversation...
Logged
I don't tolerate bickering, and I'm always grumpy.
And Lizzie Zoom says I'm a heartless bastid...and she's absolutely correct!

terry paget

  • Omega Baron
  • ******
  • Offline Offline
  • Gender: Male
  • Midsomer Norton Somerset
  • Posts: 4160
    • 1 Omega 3 Astras 1 Vectra
    • View Profile
Re: exhaust v6
« Reply #22 on: 08 May 2016, 11:03:49 »

Does the post cat lambda sensor have any function in the UK? I have the impression it is usd in German MOTs as the emission measurement, and has no function in the UK.
Logged

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #23 on: 08 May 2016, 15:25:34 »

I not changing exhaust manifolds and not mentioned changing them... there too much hassle invovled plus getting correct length primaries in such a small place isnt worth the cost of them. Plus most manifolds will alter power delivery where as standard ones are set to allow a flat torque curve across most of rev range so they are fine..

Cat back exhaust again i dont need a new one one thats one it completely fine not gonna swal for another md steel one... as in last post i decided might as well keep my system now as its quiet and works well..

3.0 downpipes yes i know are less restrictive one thwy have a smoother bend because of no pre cat and due to single cat is better designed.. however theu are all old now... so cats will be not as good as new plus most will be rusty not to mention hard to find.  Hence my reasoning behind getting a set of downpipes made with sports cats in them...

If i could find a good set of genuine 3.0 downpipes id fit them but not copys as copy cats are sh1 t .....

Head removal?? Where did thay come from never mentioned that at all.. this hread is about exhaust

Also i know not to vear to far from std port hence why when someone said fit jetex i said NO.... 2.5" bore on a twin pipe system to nig in my opinion ... on n/a anyways.
Hence my original question in first post what is std bire size and no one seems to know...


And when someone says withoit a supercharger or turbo theres not a lot of power to be had i say obviously not that into engine and tuning work...

Easy to get more power ... cams ..exhaust ..ported head... ported inlet... standalone management alter fueling and ignition ... .. cermaic coat valve train and pistons .. but this would shift power up rev range and takeaway from being a nice usable car hence why not doing it... plus cost

But i strongly believe derestricting the exhaust within reason shouldnt alter npise to much give better flow... have inlet and plenum ported and then maybe mapped..
Should see a good 20-30bhp which is only 10-15% increase but you will notice it. Same way you tell diffrrence between a 3.0 and 3.2

Logged

Nick W

  • Omega Lord
  • *******
  • Offline Offline
  • Gender: Male
  • Chatham, Kent
  • Posts: 7423
  • Rover Metro 1.8VVC
    • 3.0l Elite estate
    • View Profile
Re: exhaust v6
« Reply #24 on: 08 May 2016, 16:40:29 »

The stock twin exhaust on my 3.0l is 52mm in diameter. That's pretty big for the 1.5 engine feeding each one! The chance of you liberating 20-30hp with your suggested 'de-restrictions' is very poor. I would actually want to see proof of such restrictions before going any further, all you're likely to do is to change the volume/tone of the exhaust. Getting that much power from an expensive aftermarket cam swap might be realistic on such a small engine.


I have 3.2 manifolds on my car, and they make a small but noticeable improvement to how the quickly the engine revs over 3500rpm, but I doubt there is any measurable extra power from them. I fitted them because they became available at a low price just before I lifted the heads to replace blown gaskets; having done that, the cost/benefit/hassle ratio doesn't justify the hassle of fitting them on their own.


The V6 is a carefully designed modern engine, made using high quality castings and machining techniques: most of the traditional porting procedures are redundant as there are no misaligned bores, steps, large valve guides, massive single-angle valve seats etc. Even the manifolds and plenum match effectively, so any improvements are likely to be small and come at the cost of of proper, time consuming  development rather than the  quick skim with a die grinder that makes such a difference to Mini engines(for example).


I would expect a fully developed 3.2 V6 with individual throttle bodies to make well over 300bhp, but with a ball-park cost of about 5000 it's never going to be cost-effective. Nor is it likely to be the sort onengine that would suit an Omega.
Logged

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #25 on: 08 May 2016, 19:24:18 »

2" lovely that great to know. I wont be going bigger as that is pretty much spot on considering its a dual pipe system. if was converting to a single pipe system which im not 2.5" would be ok then hence not buying a jetex as 2.52 dual pipe system to big.

this is not a all singing all dancing engine and there is nothing on it that cannot be improved.(as with any engine) yes its modern and designed well.. but as with all engines its compromised for the global market. i work for jaguar land rover as a engineer and even our engines out the box could be improved as can fords ecoboost we use. they are made and deisgned to work well in all climates and meet all emissions standard for the market its sold in. not optimised for one place.

with throttle bodies yes you would see 300bhp no problem i believe But power would be shifted up range and it would alter characteristics of engine drastically to something i wouldnt like..

even on engines with three angle valve seats you can still improve them by altering the angle of each section and maybe placing in a 4th angle to move from stepped seats to pretty much round seats with very little flat on for valve.. this is all normal tuning practice depending on how fat you want to go..

the omega engine develops ok power standard around 217bhp. removing pre cats, and swapping 400 cell cats for 200cell cats would make a noticable improvement plus removing pre cats you alter the bend in downpipe allowing for smoother flow. doing this and then having it mapped to suit the altered exhaust you will see easily a 10% improvement over std power.

a good remap (i know omega is n/a so gain not big) to set fuel and ignition up for our climate and fuel plus mods to engine will see a few % on its own so couple that with a improved exhaust system(even fitting 3.0 downpipes instead of 3.2 downpipes) will see a improvement. not to mention the fuelling map can sometimes be a little lean top end you would gain there.

all little improvements add up. if i can gain 20bhp id be happy as previously stated a 3.0-3.2 is very different so little power increases you do make difference..




The stock twin exhaust on my 3.0l is 52mm in diameter. That's pretty big for the 1.5 engine feeding each one! The chance of you liberating 20-30hp with your suggested 'de-restrictions' is very poor. I would actually want to see proof of such restrictions before going any further, all you're likely to do is to change the volume/tone of the exhaust. Getting that much power from an expensive aftermarket cam swap might be realistic on such a small engine.


I have 3.2 manifolds on my car, and they make a small but noticeable improvement to how the quickly the engine revs over 3500rpm, but I doubt there is any measurable extra power from them. I fitted them because they became available at a low price just before I lifted the heads to replace blown gaskets; having done that, the cost/benefit/hassle ratio doesn't justify the hassle of fitting them on their own.


The V6 is a carefully designed modern engine, made using high quality castings and machining techniques: most of the traditional porting procedures are redundant as there are no misaligned bores, steps, large valve guides, massive single-angle valve seats etc. Even the manifolds and plenum match effectively, so any improvements are likely to be small and come at the cost of of proper, time consuming  development rather than the  quick skim with a die grinder that makes such a difference to Mini engines(for example).


I would expect a fully developed 3.2 V6 with individual throttle bodies to make well over 300bhp, but with a ball-park cost of about 5000 it's never going to be cost-effective. Nor is it likely to be the sort onengine that would suit an Omega.
Logged

TheBoy

  • Administrator
  • *********
  • Offline Offline
  • Gender: Male
  • Brackley, Northants
  • Posts: 99558
  • Millennium Man
    • The missus mad
    • View Profile
Re: exhaust v6
« Reply #26 on: 08 May 2016, 20:14:14 »

I think your calculations are very ambitious on a 3.2 without a fair bit of engine work or forced induction. The 3.0l may respond better to the mods, though it was built with less penny pinching to start with, hence being more powerful and more economical.
Logged
I don't tolerate bickering, and I'm always grumpy.
And Lizzie Zoom says I'm a heartless bastid...and she's absolutely correct!

jb

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • bucks
  • Posts: 216
    • 3.2 Special Auto LSD
    • View Profile
Re: exhaust v6
« Reply #27 on: 08 May 2016, 22:57:00 »

Laney, top tip for more power is to use tesco momentum which is 99/100 octane. The knock sensors advance the ignition . 3.2 engines are not unduly restricted by the exhaust and cat. On a dyno you will see 230 - 235 on momentum.
Logged

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #28 on: 09 May 2016, 04:32:00 »

i run super unleaded anyways all the time. but shell v-power. i know it automatically adjusts timing says in handbook :>

they may not be overly restricted but it still hasa terrible restriction at precat the bend isnt smooth in downpipe due to it. so i think 3.0 cat pipes be best found new type approved on on cat2you.co.uk 80quid each so thinking of buying them and welding in second lambda boss.

then going to look into recon injectors to make sure they are spot on...

then a possible remap
Logged

Lazydocker

  • Omega Queen
  • ********
  • Offline Offline
  • Gender: Male
  • Woodbridge, Suffolk
  • Posts: 18838
  • Constantly Bullied by a certain Admin
    • View Profile
Re: exhaust v6
« Reply #29 on: 09 May 2016, 08:14:59 »

i run super unleaded anyways all the time. but shell v-power. i know it automatically adjusts timing says in handbook :>

they may not be overly restricted but it still hasa terrible restriction at precat the bend isnt smooth in downpipe due to it. so i think 3.0 cat pipes be best found new type approved on on cat2you.co.uk 80quid each so thinking of buying them and welding in second lambda boss.

then going to look into recon injectors to make sure they are spot on...

then a possible remap

I'd be very careful fitting any aftermarket cat... Just because they're type approved doesn't mean they're any good ;)

That said, I've fitted cats from them to other vehicles before and they have seemed to be ok :y
Logged
Whatever it is... I didn't do it

Andyv6

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • westmidlands
  • Posts: 69
    • Elite 3.0, Vectra b3.0l
    • View Profile
Re: exhaust v6
« Reply #30 on: 09 May 2016, 08:22:15 »

I wanted a stainless system as the after market ones kept failing, so booked it in asked them to copy the standard system from the cats back with all mounting points and flanges, so basically a stock exhaust in stainless, they quoted me and I said ok go ahead.
And what I got was the flanges cut off the cats 1 centre box and 1 pipe to the back box and a bodge of hangers no flanges or joints completely welded.
Now the lambda probes have gone week and the cats are rattling, ordered new lambda probes but they are seized into the down pipes so ordered new after market cats and boy is it a pain in the arse trying to get them to fit.
I'm now binning the stainless heap of shat and going back to a normal one
Logged

kevinp58

  • Omega Knight
  • *****
  • Offline Offline
  • Gender: Male
  • kent
  • Posts: 1418
    • 2002 3.2 elite
    • View Profile
Re: exhaust v6
« Reply #31 on: 09 May 2016, 21:07:54 »

Another vote for jetex from me I got one just under 2 years ago and it wasn't that bad price 550 iirc and fitted with no problems yes 80 double outlets but I personally think it looks better than the smaller original
Logged

annihilator

  • Senior Member
  • ****
  • Offline Offline
  • Gender: Male
  • Wirral
  • Posts: 618
    • Elite,Tourer V6's
    • View Profile
Re: exhaust v6
« Reply #32 on: 10 May 2016, 10:05:28 »

Laney you have pm. :y
Logged

iansoutham

  • Intermediate Member
  • ***
  • Offline Offline
  • Gender: Male
  • SE London
  • Posts: 328
    • Omega 2.0 m/f/l est CDX
    • View Profile
Re: exhaust v6
« Reply #33 on: 11 May 2016, 18:27:32 »

Just down at profusion here at heathrow. At the moment just getting a stainless back box fitted. I was talking to the chap a full cat back system using magnaflow. He said he wouldnt go the route of 2 into 1 but would fit a crossover then bring them both into back box.
 After taking my back of he started the car and rev'd it.(what a lovely sound). Idea behind this was to get a sound level so we could decide what size rear box to put on. It now sound nice without any low down drone :y

Hi, I am planning on taking a trip to them in a week or so to price up some exhausts for my show cars. What sort of price did you pay for the rear box?
Logged

B52

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • Glasgow
  • Posts: 103
  • 02 MV6
    • View Profile
Re: exhaust v6
« Reply #34 on: 12 June 2019, 21:04:05 »

I realise this is an old thread but info only, it looks like Jetex is stopping its Omega exhaust - saloon not available, maybe limited estate sets left
Logged

sjc

  • Senior Member
  • ****
  • Offline Offline
  • Gender: Male
  • Alloa, Scotland
  • Posts: 687
    • M5 ; 3.0 MV6 Manual
    • View Profile
Re: exhaust v6
« Reply #35 on: 13 June 2019, 09:08:54 »

I realise this is an old thread but info only, it looks like Jetex is stopping its Omega exhaust - saloon not available, maybe limited estate sets left

They will do a production run if you can get 10 or more confirmed buyers, speak to Neil @ Jetex.  Have done this a couple of times including a batch for 3L 24v Carlton GSi.

The Jetex system on my Omega is over 10 yrs old, still looks and sounds as good as new ;)
« Last Edit: 13 June 2019, 09:17:43 by sjc »
Logged
If you Elite an MV6, does that make it an MVee-leet?

B52

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • Glasgow
  • Posts: 103
  • 02 MV6
    • View Profile
Re: exhaust v6
« Reply #36 on: 13 June 2019, 17:22:56 »

Good to know thanks - I've bought a Gerlach for MoT but it's not forever
Logged

laney101

  • Junior Member
  • **
  • Offline Offline
  • Gender: Male
  • liverpool
  • Posts: 215
    • omega elite v6
    • View Profile
Re: exhaust v6
« Reply #37 on: 16 June 2019, 09:15:48 »

im going custom for mine next year.

cheaper and can have made to my spec with correct original tips used also
Logged
Pages: 1 2 3 [All]   Go Up
 

Page created in 0.158 seconds with 22 queries.