456 GT exhaust mod

Hi George,

I have X-Ost mufflers on my 456 ... nice sound and not to much loud Very civilised inside the cabin

On the testarossa that i owned , it had a tubi exhaust also very very good

 

George- The simplest way to a little more growl without killing the quiet cruise is to replace the center muffler/resonator with straight pipes like those Bradan sells. Will pick up a bit of hp and torque and probably fractionnally improve fuel consumption.

http://www.ferrarichat.com/forum/456-550-575/437351-bradan-456-resonator-delete-pipes.html

 

Hi

Yes , i would say that it sounds like mine...

Have a look here :

x-ost maranello srl Maranello - Home

Terry is right , if you change the central muffler it will change the sound I haven´t done that on mine yet...

 

I have installed TubiStyle mufflers on my 456M. I like this sound much more than the serial sound note, but this is a very personal matter of taste.

My feeling after 3+hours driving at 3-4000 rpm? No idea, latest after two hours do I need a coffee break.

BTW, I support the suggestion of Taz with the straight pipes, was also my first plan. But this solution can not be realized on the 456M.

[ame=http://www.youtube.com/watch?v=ZSqVvFSGUYY]Ferrari 456M GT - TubiStyle exhaust muffler while driving - YouTube[/ame]

 

Daniel- Replacing the center muffler/resonator on the 456M is very easy and has been done by multiple owners. Now that Bradan makes a bolt in straight pipe set, it is even easier. See the post I referenced up above to see the pipe set.

 

Very interesting thread. I will have to refer back to the vids when i come to change mine.

 

I am waiting on the winter to break and the salt to clear so I can get Nouvalari exhaust installed on my 550. There are many youtube videos with comparison exhaust upgrades you can look at and listen to to get a sense of what you may want. I am also making a "Transformation" video to show the tint, brakes, and exhaust that I am upgrading.

 

Can definitely do the straight pipe on the 456M. Here's mine - it's growls nicely and calms down when cruising. I would recommend starting with this mod. Here's vid: http://vimeo.com/89875340

 

Thank your Taz! It's a pity, I should have known that earlier. Then I had contact with Capristo in Germany, they told me that the replacement oft the center muffler/resonator doesn't work on a M GT. Therefore I decided to go with the TubiStyles from my dealer.

 

Daniel- Sounds like they were trying to sell you an exhaust system. People like that salesman should be kicked in the nuts for passing out bad information. Their exhaust systems are good and they do not need to do that.

 

I have to be fair with Capristo. They told me that they didn't have produced center mufflers for the M GT because of technical reasons (just for the GT), they didn't have tried to sell me something else.
However, finally I'm absolute happy with the Tubi's.

 

I have tubis and the Braden pipes. Works for me.

 

Replacing the 456 center muffler resonator always brings more sports car sound.

Fabspeed Motorsport USA has dyno developed high performance X pipe muffler bypass pipes. Fabspeed X pipes are race designed pipes that have a high flow X designed in that has an internal window that allows each 6 cylinder bank or side of the 12 to work together to make more power and better sports car sound.

It is public domain that X pipes are the preferred exhaust for professional racing teams from ALMS, grand am racing, to NASCAR to European sports car racing. From Aston Martin, Maserati BMW Motorsports a front engine car making a lot of power acquires increased torque and useful power when the undercar exhaust banks are merged together in a X pipe configuration.

At fabspeed we have dyno and street tested X pipes for many years and there is a significant power increase and better exotic sports car sound by using a X pipe under all cars when possible.

Another option for Ferrari 456 owners are high flow catalytic converters as high performance replacement parts for the stock restrictive Ferrari catalytic converters. As these cars age the factory catalytic converters are staring to ail and new Ferrari 456 catalytic converters are very very expensive. Fabspeed has 200 cell high flow sports racing cats that are a direct bolt on replacement for the OEM parts. You will get more sports car sound as a result.

In addition for customers that want even more power sportscar sound and are not concerned with emissions fabspeed can offer you 456 catbypass pipes straight pipes. The big twelve really breathes with sport cats and or straight pipes!
For more information
Ask for [email protected]

 

Joe- X-pipes on a V12 will produce less hp and torque than straight pipes. Some people do prefer the sound from X-pipes. To confirm, have your techs take the same 456/456M with same muffler set and fit a set of your X-pipes and a set of same diameter straight pipes and do dyno runs on each. That has already been done on the Maranellos and the straight pipes produced more hp and torque throughout the rev range.

12 cylinder engines produce so many exhaust pulses that extraction of exhaust gasses is already near optimum, and adding an X-pipe just slows down the flow. Your X-pipes will be a big improvement over the OEM resonator/center muffler cork, which has a cross pipe, and will sound great, but will not produce more hp than straight pipes.

X-pipes are preferred for V8s with cross-plane, 90 degree, crankshafts that are effectively 4 v-twins on the same crankshaft. They are not preferred for V12s or V8s with flat-plane, 180 degree crankshafts. The racing series you quote are not applicable to V12s or flat plane V8s.

 

Taz I've always been curious if the Bradan dyno charts that show the straight pipes making more power are the Bradan Straight Pipes vs the stock resonator, or if they were actually the Bradan Straights vs "Whose" X pipe?

I tried to follow this back to the source but the trail has gone cold.

Perhaps you or Dan could clarify this?

 

John- Bradan did just the OEM resonator vs straight pipes dyno runs. The actual apples to apples comparison of X-pipes vs straight pipes was done by an Australian owner/tuner who no longer posts. Do not know if Dan at Bradan saw those results or not. He only makes straight pipes.

There will not be much difference in the two, but claiming X-pipes make more hp than straight pipes is just not true. More than the original resonator cork, sure, and if I already had an X-pipe, I surely would not swap it for straight pipes for the small increase in hp/torque.

Also correlating cross-plane crank V8 exhausts to V12s is not relevant and pure marketing. Some owners do like the X-pipe sound better, and for the street that is a good enough reason to use one. My straight pipes and HGTC mufflers sound great, though.

 

I posted this monograph on the subject three years ago: INTRODUCTORY TECHNICALITIES / AJ6 Engineering

Here's an excerpt from the article:

It is true that a cross-over can benefit conventional V8 engines (with two plane crankshaft) but only because they have an uneven firing sequence along each cylinder bank, which creates the rather delightful V8 exhaust note. A consequence of having two cylinders firing consecutively on each bank is that the flow rate is briefly doubled, then later in the cycle the long gap between firing impulses causes it to be halved, compared to the average flow rate. The temporary high flow rate means the V8 can benefit from using larger pipe sizes than other engines and a cross-over pipe can help to even out the impulses. It is not obvious to the eye but the Jaguar V8 incorporates a cross-over within the main silencer box.

A V12, on the other hand, has equally spaced firing impulses along each bank creating an even sequence of pulses. There is no flow variation to require a balance pipe and the system does not have to contend with brief periods of peak flow so pipe sizes can be smaller. The only reason the V12 E Type had a balance pipe was simply to tune the exhaust note.

 

Barry- Yup, that about covers it. Must be some reason Ferrari eventually went back to all straight pipes starting with late 575Ms. Same thing actually applies to flat crank V8s, too, which also have self-extracting exhaust systems.

 

FerrariChat.com - View Single Post - 550 Pipes (again)

 

Barry- That is the one. Long time ago. Would not have thought it was that much hp difference, but....

Theory matches results. Here is the graph showing X-Pipes vs straight pipes. ~35 hp more at the flywheel after corrections for gear losses.
Image Unavailable, Please Login

 

Terry, Stephen's post and dyno helped me decide on straight pipes for my 550. Classic Coach had fabricated X-pipes for me utilizing a Burns Stainless crossover but there was a slight problem with the fit. Then I spotted this dyno graph and I had them make me straight pipes instead:

http://www.ferrarichat.com/forum/138022787-post55.html

http://www.ferrarichat.com/forum/138023207-post56.html

http://www.ferrarichat.com/forum/138024054-post57.html

 

Here's the whole thread about X-pipes vs straight pipes: http://www.ferrarichat.com/forum/456-550-575/202062-question-about-550-x-pipe-exhaust-mods-6.html

Thank you again, Stephen.