575 X-Pipe

cgt- V12s do not need an X-Pipe. Go to any muffler shop and have them replace your center muffler/resonator with straight pipes, like the factory did in Summer 2003. Save the old center piece, because you may want ot reinstall.

Search for "550 exhaust" and "575 exhaust" and you will find all the info you need.

Be advised if you do this with no rear muffler/silencer as currently configured, your car will be extremely loud. Loud enough to attract the police and turn the interior of your car into a reverb box.

Taz
Terry Phillips

 

cgt,

Go with straight pipes and don't worry about your car being too loud. It won't be. A friend has a 575M with factory straight pipes and straight-through backboxes like yours. It sounds just fine and probably like what everyone in this Forum is after.

Barry

 

Barry- My 575M with factory straight pipes and Novitec supersound rear exhaust was extremely loud. Other 550 owners with straight pipes and regular Tubis thought they were too loud. All a matter of taste and what your wife, neighbors, and the cops can stand.

cgt- Search for all the posts on 550/575 exhausts before you make a decision. If you have a muffler shop make straight-through pipes, they will not be too expensive. Fit them and see what you think. For me and a bunch of Maranello owners, they would be too loud. If they are too loud for you, refit your center mufflers or an aftermarket equivalent and no problems. Then sell the straight pipes on FerrariAds. If you have 2000 hours in jet fighters, and were too stubborn to wear foam ear plugs under your helmet, like my brother, they may be just right. Deafness helps.

Taz
Terry Phillips

 

Terry,

There's something about 2 1/4" rear straight pipes with tips that cuts down on the noise. I think the Novitec and other similar rear boxes add resonance and decibels. The set-up I referred to is not excessively loud even with wide open throttle.

You must have liked going supersonic and leaving a lot of the noise behind you.

Barry

 

But Terry, you made the right decision with those SA rear boxes. And you haven't violated the Helmholtz Resonance Theory....
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cgt,

The primary reason for getting rid of the center resonator is the restriction of flow at the outlets as illustrated.

Straight pipes are cheaper and probably more indicated for V12 engines than are X-Pipes. I had a set made up for my 550. I retained my stock valved rear mufflers.

With straight pipes, you'll notice a few more decibels over what you have now. If you dyno your car, you'll notice a gain in HP.

The Helmholtz Resonance equation I posted refers to Ferrari's variable exhaust geometry provided by their valved rear mufflers. The valves provide some back pressure at lower RPMs to increase torque in that range resulting in somewhat faster acceleration.

So go ahead and have a set of straight pipes made up for your car. You might like the sound. If you need more sound, then go with aftermarket rear boxes like Novitec, Kreissieg, etc. These rear boxes provide resonance and decibels. Novitec, Kreissieg and a few others offer valved mufflers in addition to their non-valved mufflers.

Barry
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On my 575 I have straight pipes and actually the original backboxes. I tried with Tubi and SuperSprint backboxes and both where too loud for me.
The SuperSprint where a little bit better than the Tubi, with less resonations but still loud.

I think the best sound and performance would be to exchange the headers and main cat's with something "better". Does anyone knows a company producing something for the 575?

Or perhaps Terry knows if it would be possible to install the original 550 headers and cat's into a 575? I suppose this could be a good option, if doable!

Regards

Renato

 

Renato- X-OST makes an entire exhaust system for the 575M, including new cats and center pipes. They make valved and unvalved rear exhausts, too. I believe Kreis-Sieg makes such a system, too, but not sure about the cats. They do make cat bypass pipes.

The expensive Kreis-sieg and Capristo rear systems have the best sound I have heard from a 575M. Capristo makes a remote control solenoid, too, which allows you to select valves open or closed on demand.

Taz
Terry Phillips

 

As a follow on from the 456 Center muffler thread and this thread is an issue that has me puzzled. The original mid muffler on the 456 and the 550 appear to mix the exhaust and act as an "X pipe". The various aftermarket mid pipes advertised appear to lead the exhaust from the left and right banks of the V12 to the left and right mufflers without mixing. Barry W's twin pipes accomplish the same thing and are well shown with excellent photos.

An exception to this is the Kreissieg, for example, which appears to have a true X-pipe ( http://www.vividracing.com/catalog/meisterschaft-sus-f1vt-catback-exhaust-ferrari-550575-9606-p-74841.html ).

If there is a true mixing (X-pipe effect) at this point, what effect does it have when it is eliminated with a simple pipe front to rear?

Whilst it has been 40 years since I studied physics, the effect of each cylindre's pressure wave coming down the pipe would be removed at the "X-pipe" and a homogenous exhaust goes through to the right and left rear mufflers. At this point it would produce a slight(?) back prssure effect. In the individual pipe scenario each pressure wave arrives at the rear muffler and is eliminated without any back-pressure effect.(with no valves)

Is this all just theoretical hypothesizing or is the a logical reason there is a mixing at the mid-muffler. I note the theory that the "valves" provide an element of back-pressure to improve low end torque, which of course Formula 1 cars do not have to worry too much about but road cars do. Also Taz and Rifledriver's comments on the 355 exhaust stick in the back of my mind.

I am also unsure what effect the Catalytic converters have on this "theory".

As an aside I have removed the vacuum line to my valves and wired them open, although Taz's solution seems more elegant" to open the valves must require a helluva vacuum as they are damned hard to open manually. I notice only a slight improvement in "sound" at idle and driving and NO difference in "low end torque", although with 588nm of torque, seat of the pants driving would not show this IMHO.

 

Philip,

I would love to see a 550 center resonator sectioned to demonstrate if there is any mixing of exhaust gases from the left and right banks. The picture of the restricted outlets was originally posted by Stephen S down your way.

The fact that Ferrari went to an unmuffled straight pipe set-up in the later 575Ms leads me to believe that there is no mixing of exhaust gases in the center resonator. This would make sense when one thinks of the Helmholtz Resonance Principle and the variable exhaust geometry design incorporated into this system.

I've read that compared to a conventional V8 engine with a two-plane crank, the V12 has equally spaced firing impulses along each bank creating an even sequence of pulses which obviates the need for a crossover pipe to to even out the impulses. The V8 engine, having two cylinders firing consecutively on each bank, would benefit from a crossover pipe to help even out exhaust pulses. Thus my previous statement that straight pipes are "probably more indicated for V12 engines than are X-Pipes."

Anyway, Stephen S posted some interesting findings in this thread:

http://ferrarichat.com/forum/showthread.php?t=103601

I chose to retain my stock valved rear mufflers so as not to violate the variable exhaust geometry built into the system and the benefit derived from it, that is an increase in back pressure at low RPMs to increase low end torque.

Barry

 

Barry

Good explanation in your last post re V8 & V12. However the final link in the chain is the headers. Many moons ago when I used to own V8s, and well before Cat converters and unleaded petrol were even thought of, they were cheap and fun to play around with in making up 'tuned headers' .. using absolutely no science whatsoever and merely following the suggestions of a very good friend who owned a muffler shop and was into racing. Of course that would be prohibitively expensive nowadays and the dash would absolutely light up with 101 warning lights .. so I guess that would be not on, however would be fun.

I think a few terms need to be crystalised .. my definitions are open to correction/adjustment and depend sometimes on which country you are in.

"X pipe" - behind the headers the pipes physically join and share exhaust gases.
"Siamesed" - same as X pipe, however the pipes join in a longitudinal plane for a set distance.
"straight through pipes" as per Barry's photo above .. completely seperate right and left banks.
"Headers" - start at the exhaust outlet and go to the Catalytic converters. Having said that it appears that the 575 has "pre-catalytic converters" within the headers and its own lambda sensor, seperate to the one where the main Cat converters are.
"Tuned Headers" as for 'headers" The individual pipe from each cylinder is of a different length to enable the exhaust pulses to arrive at the point where the pipes all join into one at different times.
'Muffler', 'silencer' - (according to Barry W) - any device designed to adjust back pressure and increase resonance and hence 'noise'
"catalytic converters' - an abomination forced on us to make the simple exhaust sytem as complicated as possible.

So my conclusion from the above, as an experiment with increasing expense:
1. Replace centre 'muffler' (550's and early 575s) with straight through pipes.
2. Wire open the valve on standard exhaust, or Terry's elegant solution.
3. Replace rear mufflers with aftermarket, bearing in mind that a valved option may be an interesting solution. However valved V non valved are about $1500USD more expensive.
4. Trade car in on a 599 or a 365 Daytona or GTC .. then go through exercise again

Philip C

 

Love all this specialist info and excellent advice from people who really know their stuff!
Seems like 550/550 discussions on exhaust mods/sounds is a recurring theme and this thread is reaching pretty much definitive conclusions.
I'm going to change to straight pipes on my '99 550 and change the air filter. I'll leave the back boxes in but wire them open.
I couldn't find 'Terry's elegant solution' to the valve opening issue so if anyone can give me the link that would be great.
Has anyone come across a way of manually opening and closing the exhaust valves on the standard back box? Maybe even a simple manual wire pull, even if it meant leaning under the car occasionally and pulling it closed to keep the wife happy for the monthly shopping trip?

 

Paul- Here you go. Just about everything on the 575s technically that I have found, I have tried to put in the Assembly Numbers vs VIN thread. I continue to add details and probably should actually rename the thread to 575 Technical Thread or something similar.

All this technique involves is rerouting vacuum hoses and perhaps adding a short piece of vacuum hose. The 575M (and 550 and SA) is a failed close system on the bypass valves. No vacuum equals valves closed. The 599 and 430 are the opposite and fail open.

http://www.ferrarichat.com/forum/showpost.php?p=138795870&postcount=133

Taz
Terry Phillips

 

Right, Philip. Those were the days!

Yup! We're speaking the same language.

I'm not sure about the 599, but the 365 Daytona and GTC/4 need not be fiddled with. They sound just right!

Philip, I think the Factory did pretty well tuning the 550 headers. There are pre-cat exhaust restrictions present in 2000 and newer 550s which cost a bit of performance.

Barry

 

CQT and Barry, when talking about the rear "muffler" you describe straight thru pipes (which have been explained at length) and Tubi straight backboxes with no "silencer".

Are you referring to these, Tubi Part No. 01069661000.

I would have thought that this setup would have been L-O-U-D.

Philip C
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Paul,

The straight pipes and BMC filters are the way to go. Follow the maintenance protocol for the filters for optimum protection and performance.

You'll find that the center straight pipes and stock rear boxes render a pleasing idle note. Not too loud, but the 550 will make its presence known. Leaving the rear muffler valves functional, you'll note a quiet cruise at highway speeds not much louder than stock with the center resonator in place. Hard acceleration and wide open throttle yield an aggressive exhaust note. It's fun to produce that sound "on demand" when cruising and the time comes to pass a slower car.

Terry's suggestion regarding valve control is worth adding to the system to satisfy both you and the wife.

Barry

 

Philip,

I haven't heard the Tubi straight through rear pipes as you've pictured. But a friend who owns a later 575M with Factory center straight pipes had a set of custom stainless steel rear straight through pipes with double-walled ("intercooled") Borla tips (pictured below) fabricated for his car. The exhaust note is loud but not as loud as with some of the other aftermarket rear mufflers on the market. There are no rear boxes present to produce resonance/noise.

I'm sure the Tubi rear pipes you pictured would yield the same result.

Barry
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For those interested here are a few examples seen from trawling the net.

the two Tubis are taken from the Carobu website and retail for $2561usd (Pipe & Tips)and $3811usd (muffler & tips) .. which must be the most expensive tips with a pipe attached available in Ferraridom.

The full setup as shown is from supersprint ( http://www.supersprint.com/ ) price unsure. An Australian company appers to import these at a cost of $12,000aud for the manifolds to the rear cats !!

Philip C
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Philip,

Rear pipes and tips can be made up for a whole lot less, of course. And you can choose the tips you like.

The Borla tips I posted happen to look pretty good, looking very much like Superamerica tips.

Barry

 

Philip- Headers are pretty. You could pick up a ratty 308 GT4 for the kind of money the whole system costs. Maybe.

If anybody wants straight-through pipes with valves, I can show you where you can pick of two complete sets of original 575M rear mufflers for $400 each. Cut off the two permanent tailpipes, unbolt the valved tailpipes, and have your muffler shop weld straight pipe Y sections to each, with connectors for the valved tailpipes. Presto, loud and louder.

http://cgi.ebay.com/Ferrari-575-OEM-Mufflers-w-Exhaust-Valves_W0QQitemZ380087398022QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item587ef96e86

Anybody except me worried about having oil on the BMC or K&N filters upstream of the MAF meter? That is the reason I have not installed either on any of my cars.

Taz
Terry Phillips