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Discussion Starter #1
Hi all. Anyone got any pointers about sourcing decent free flow exhaust components for the 156 V6? (A Wizard would be lovely but bit too pricey).

I already have a stainless Supersprint backbox, so really I'm looking for a reasonably priced larger diameter (2.5"?) centre section in stainless and possibly same diameter downpipes too.
Cybox don't appear to make 156 items except for a cat replacement box (and the quality isnt all that great IMHO)

Is this a custom fabrication job?? Any suggestions gratefull received. :wink_org:
 

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Hi all. Anyone got any pointers about sourcing decent free flow exhaust components for the 156 V6? (A Wizard would be lovely but bit too pricey).

I already have a stainless Supersprint backbox, so really I'm looking for a reasonably priced larger diameter (2.5"?) centre section in stainless and possibly same diameter downpipes too.
Cybox don't appear to make 156 items except for a cat replacement box (and the quality isnt all that great IMHO)

Is this a custom fabrication job?? Any suggestions gratefull received. :wink_org:
Had a ragazzon full stainless system on mine for the 6 years I had it. I seem to recall parts were interchangeable with standard and the single outlet back box looked standard(ish) sound was nice without being to noisy
 

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Discussion Starter #3
Had a ragazzon full stainless system on mine for the 6 years I had it. I seem to recall parts were interchangeable with standard and the single outlet back box looked standard(ish) sound was nice without being to noisy
Thanks Richard - if the Rag parts were interchangeable, was the diameter the same as stock then? I assume the centre section must have been silenced as I had an unsilenced centre pipe on my Spider and it was LOUD!
I think that Ragazzon parts are pretty much the same price as Wizard though...:ermm:
 

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Question - why?

I've got a Wizard cat back on my 2.5. Yes it was pricey, but it sounds epic. For the life of me, I can't discern any power increase - however, I tend to rev the engine harder when I am having fun because it sounds so awesome above 4K.

If you're looking for more power, I think you'll be disappointed - unless you replace the whole system, bin the cats and get it remapped, I don't think you'll get anything material, the standard system is good. If you want loads of noise, then a Wizard with no intermediate box is perfect - but possibly too much if you've decatted the manifolds. If you want a civilized rumble, with a proper noise above 4K, then get the version with the intermediate box.

I haven't seen a better balanced exhaust out there. I went through this with my brother in law's 147 - all of the aftermarket stuff either didn't fit, was stupidly loud and/or badly made.
 

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Discussion Starter #5
Thanks for the input mate. The answer to the question is:

To get a freer flowing exhaust that sounds great higher up the rev range (as you say) but that isn't ASBO territory when parking or trickling through the neighbourhood!
(I'm also installing 3.2 inlet runners, with a remap and maybe also a sports cat, (car is a CF2 so no manifold cats), so need to watch that the volume doesn't "creep" up.

I know that exhaust tone is a very personal thing and what pleases my ears may not please another. The sound clips of Wizard pipes I have heard have all been GTV's and they do sound ace, if just a little bit "toppy" or raspy to my ears. I like a bit of pop and crackle on the overrun too. My Spider sounds just right to me: Rumbly on idle and builds to a howl rather than a fizz at the top end. That has standard manifolds, Cybox equal length downpipes, Ragazzon silenced centre and a straight through tailpipe. Doesn't drone on the motorway either.

The 2.5 V6 tends to sound "fizzier" than the 3.0 to my ears - because it is smaller capacity maybe?
 

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Thanks for the input mate. The answer to the question is:

To get a freer flowing exhaust that sounds great higher up the rev range (as you say) but that isn't ASBO territory when parking or trickling through the neighbourhood!
(I'm also installing 3.2 inlet runners, with a remap and maybe also a sports cat, (car is a CF2 so no manifold cats), so need to watch that the volume doesn't "creep" up.

I know that exhaust tone is a very personal thing and what pleases my ears may not please another. The sound clips of Wizard pipes I have heard have all been GTV's and they do sound ace, if just a little bit "toppy" or raspy to my ears. I like a bit of pop and crackle on the overrun too. My Spider sounds just right to me: Rumbly on idle and builds to a howl rather than a fizz at the top end. That has standard manifolds, Cybox equal length downpipes, Ragazzon silenced centre and a straight through tailpipe. Doesn't drone on the motorway either.

The 2.5 V6 tends to sound "fizzier" than the 3.0 to my ears - because it is smaller capacity maybe?
We use the same resonator on the GTVs as on the 156 V6 & GTAs, but 2.5" diameter on the GTV V6 and GTA models instead of the 2 1/8th inch diameter we use on the 156 V6s (although we can do 2.5" instead as a no-extra-cost option - a few 3 litre conversion owners have bought these from us over the years). Also because the GTV box is further back, the extra length of the tailpipes changes the sound considerably so they don't really sound the same on the 156/GT. Definitely deeper on the 156/GT.

Good comparison here between Wizard & Ragazzon:



I wouldn't worry about a sport cat on your 2.5 - my lightened/balanced/GTA-cammed 3 litre conversion did 250hp on a rolling road breathing through a standard 2.5 CF2 middle cat, it just had the exhaust manifolds externally re-welded and ported internally, equal length downpipes were fitted and a 2.5" cat-back system. They're good quality cats, not particularly restrictive and should last the life of the car, plus it is helping you to achieve the non-ASBO sound you're looking for :lol:, a sport cat would be much louder, reason being the CF2 main cat has a silencer built into the casing as well as the cat. That is why a V6 with CF2 manifolds & CF2 middle cat is much quieter than a V6 with CF2 manifolds and the CF3 twin middle cats.
 

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Discussion Starter #7
Thanks for that Dan, much appreciated.
Maybe I'll try and keep the original cat then, although the MOT garage are currently saying it could be defective as the emissions are quite high?

So where did you get your equal length downpipes from? Are they Wizard ones?
 

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It could well be there is something wrong with the cat if emissions are high, or a running issue. Do you have a print out from the last MOT emissions test?

The equal length downpipes were made by Wizard, a prototype really. To be honest they are not ideal, to make them equal length, ground clearance is reduced. Consequently these have had to be repaired a few times and they're a bit annoying on bumper/cambered backroads as they scrape. We never went properly into production with these, I think there are 4 units out there somewhere including my own, each slightly different to each other as we tweaked the design. We scrapped the jig a couple of years back, so can't build anymore now.
 

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Discussion Starter #9
Yep - sounds familiar, I have to be careful in the Spider now, as the Cybox EQ pipes cross over and now my ground clearance is about 4 inches under them.
Not ideal and I have standard springs too. They do sound lovely and creamy though :wobble:
 

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Discussion Starter #11
It could well be there is something wrong with the cat if emissions are high, or a running issue. Do you have a print out from the last MOT emissions test?
Yes, I think so - I'll dig it out and quote it. The car is still in the garage at the moment getting some additional tlc, so I won't get my hands on the latest readouts until it returns. The garage suspect it may be over fuelling rather than a cat problem but still working on it.
 

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sorry for the necro...

I'm about to get a centre silencer for my 156 2.5 2002. just not sure what to look for (shorter than the factory one or longer, same length; what outer diameter - not the perforated part, etc). As everyone I'm looking for the "Wizard sound", at least trying to get close to it :D. Current setup for the exhaust is: CF2 manifolds, custom made equal length front pipes, sport cats, original rusty centre silencer, ragazzon end (2x70). Don't really need to be louder so must have some kind of silencer, but what design? It will be custom made.
 

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Hello Alfa owners.

Sorry to hijack the thread as well, but I am also interested and this thread has already some nice advice.

The front pipes of my 156 2.5 are shot and need replacement as soon as possible. My actual setup is CF3 standard + unknown 2x80 silencer. It is is already quite loud. I aim to have a nice but not loud noise because I am daily driving it with quite high mileage (~4000 kms/month).

I am considering equal length pipes as they are often recommanded. However Wizard exhaust says there is no benefit on CF3 exhaust lines because the two cats are placed differently. So is there any benefit at all? If so, where to buy for front pipes with no reduced clearance? TiboV6, did you made your front pipes yourself?

Also, I've read many things about decat manifolds, most people say it's better for more power and less heat under the bonnet, but some also say that it's not so great because of reduced torque and increased noise. So, again, what is it about it, and where to buy? (The Wizard manifolds are highly prized but also highly priced!)

Many thanks!
 

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hello, my car is cf3, but replaced the manifolds for cf2. then a local exhaust shop made equal length front pipes from mandrel bent pieces. then the cat section, they are sport cats next to each other, not like on the original cf3 main cats (where one side is closer to the back of the car). custom made centre silencer (packed with steel shavings, bigger diameter than the oem silencer tho). ragazzon end. it is loud, at least at high revs, but not a police magnet.

about the torque and stuff, with remap and gta intake mods my car produces 200+Nm from 1500rpm, 220Nm from 1750rpm with 246Nm max at 5200rpm. 219PS maximum power.


Hello Alfa owners.

Sorry to hijack the thread as well, but I am also interested and this thread has already some nice advice.

The front pipes of my 156 2.5 are shot and need replacement as soon as possible. My actual setup is CF3 standard + unknown 2x80 silencer. It is is already quite loud. I aim to have a nice but not loud noise because I am daily driving it with quite high mileage (~4000 kms/month).

I am considering equal length pipes as they are often recommanded. However Wizard exhaust says there is no benefit on CF3 exhaust lines because the two cats are placed differently. So is there any benefit at all? If so, where to buy for front pipes with no reduced clearance? TiboV6, did you made your front pipes yourself?

Also, I've read many things about decat manifolds, most people say it's better for more power and less heat under the bonnet, but some also say that it's not so great because of reduced torque and increased noise. So, again, what is it about it, and where to buy? (The Wizard manifolds are highly prized but also highly priced!)

Many thanks!
 

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I always suggest looking at evidence from a known reliable source. Given how poor the torque characteristic is for the 2.5, I'd have a look at these pages. Frankly, the Euro 3 may have lower torque figures but it has a fatter torque band so the Euro 2 only makes sense if remapped with a higher rev limit.
https://www.squadra-tuning.nl/chiptuning/alfa-romeo/156/2-5-v6-24v/
https://www.squadra-tuning.nl/chiptuning/alfa-romeo/156/2-5-v6-24v-2/

To keep noise from being too high, 2.5 needs a silenced centre pipe to take the edge off.
Alfa Romeo Shop - Tuning, Styling, Fanartikel und Modellautos
 

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I always suggest looking at evidence from a known reliable source. Given how poor the torque characteristic is for the 2.5, I'd have a look at these pages. Frankly, the Euro 3 may have lower torque figures but it has a fatter torque band so the Euro 2 only makes sense if remapped with a higher rev limit.
https://www.squadra-tuning.nl/chiptuning/alfa-romeo/156/2-5-v6-24v/
https://www.squadra-tuning.nl/chiptuning/alfa-romeo/156/2-5-v6-24v-2/
When checking their numbers, I am amazed of how torquier is the 3.0 compared to 2.5… That is far more desirable for a daily car.

To keep noise from being too high, 2.5 needs a silenced centre pipe to take the edge off.
Alfa Romeo Shop - Tuning, Styling, Fanartikel und Modellautos
The standard exhaust line doesn't have an intermediate silencer on CF3 engines, does it?
Because mine has a simple tube, which would explain why it is so loud.
 

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https://www.alfashop.co.uk/parts-shop?Make%2FModel=ALFA+ROMEO+156&Part+Type=EXHAUST+PIPE&Product+Group=EXHAUST&page=2

The 2.0 JTS and 2.5 V6 have the same rear sections. On the link I posted, there is an IMASAF centre pipe which has a small absorption silencer which should take the edge off things if a sport rear silencer is used.

On my JTS, I used a smaller 2" pipe and rear silencer as 2" is thought to be good for up to 200bhp before it becomes restrictive. I went this way to increase gas velocity to make it more musical.

The link below shows both options. As said, the group N pipe without silencer is probably a bit loud.
https://www.gazzellaracing.com/cart.php?target=category&category_id=1964

AFAIK, Bosal is the only exhaust company who can supply an OE style silenced CF2 catalytic converter (aftermarket types are a bit noisy- same advice for CF2 Twinspark).
http://www.bosal.com/en/catalog/exhausts?make[0]=ALFA%20ROMEO&modelrange_computed[0]=156&fueldescription[0]=Petrol&stroke[0]=2.5
 

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Couldn't get more clearance than this
Have you got a photo under the car from the front, like this?

First photo is Wizard downpipes on a GTA with CF2 manifolds, second photo is Cybox EL downpipes on a GTA with standard manifolds.

You should be able to get better ground clearance with EL on CF2 manifolds than EL on CF3 due to the angle of the flanges. But CF2 manifolds give reduced clearance at the front of the front bank downpipe and there is nothing you can do about that, even stock 156 2.5 V6s often have flattened off pipes here through scraping on the road. 3rd photo shows a CF2 downpipe which has been 'skidded' to avoid rubbing through (although a tighter radius bend would have helped in this case, it'd still be worse than stock CF3 due to the position of the end of the manifold being so far forward). 4th photo shows EL downpipes on my old GTV V6 (CF2), you can see how the rear bank pipe has been hitting the ground too, not sure what brand these were. 5th picture shows the damage.

Getting a set custom made on the car for maximum clearance is the best way to do it, but I still don't think you'll end up with as much clearance as a pair of well designed downpipes following the standard route.
 

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