Exhaust design questions
Discussion
Afternoon all!
I'm trying to design a new exhaust system for a ferrari mondial / 308 / 328 (3.0L V8)
I have a good background in exhaust construction and TIG welding, so putting it together is no problem. However i have no experience building an exhaust to get a certain sound. you want a ferrari to sound like one!
I don't have a lot of space to work with, so the whole thing needs to be compact (See pic)
So my questions are:
- Pipe bore:
The original is a 2.5" bore into the box, i think ill keep it 2.5" all the way through
- X-piece or not?:
A lot of performance exhausts have a x-piece to allow cross-talk between the 2 banks on the V8. I intend to make something like this by getting 2 u-pieces, grinding off the outer part of the U's and welding them together, meaning i can easily make the appropriate sized hole.
Is this necessary?
- sound:
It has to sound like a ferrari, and be quite loud, so i dont want to take out too much of the high pitch (i guess?)
This is what I'm trying to replace:
I'm trying to design a new exhaust system for a ferrari mondial / 308 / 328 (3.0L V8)
I have a good background in exhaust construction and TIG welding, so putting it together is no problem. However i have no experience building an exhaust to get a certain sound. you want a ferrari to sound like one!
I don't have a lot of space to work with, so the whole thing needs to be compact (See pic)
So my questions are:
- Pipe bore:
The original is a 2.5" bore into the box, i think ill keep it 2.5" all the way through
- X-piece or not?:
A lot of performance exhausts have a x-piece to allow cross-talk between the 2 banks on the V8. I intend to make something like this by getting 2 u-pieces, grinding off the outer part of the U's and welding them together, meaning i can easily make the appropriate sized hole.
Is this necessary?
- sound:
It has to sound like a ferrari, and be quite loud, so i dont want to take out too much of the high pitch (i guess?)
This is what I'm trying to replace:
Edited by darkcat on Wednesday 28th November 18:13
You need a copy of this if you want to get anywhere close with only 1 iteration:
http://www.ricardo.com/en-GB/What-we-do/Software/P...
otherwise, get chopping / modding and see what you get regarding sound quality!
http://www.ricardo.com/en-GB/What-we-do/Software/P...
otherwise, get chopping / modding and see what you get regarding sound quality!
For simplicity's sake, I'd try and copy the original design, and maybe use less packing or baffles, at least then, it would be too different apart from the sound.
Different length pipes, different bores, different designs will have knock on effects that might makes things better, but more likely would make it worse at certain rpms.
Different length pipes, different bores, different designs will have knock on effects that might makes things better, but more likely would make it worse at certain rpms.
Max_Torque said:
You need a copy of this if you want to get anywhere close with only 1 iteration:
http://www.ricardo.com/en-GB/What-we-do/Software/P...
Would I be correct in guessing this would be expensive and bamboozling to the layman?http://www.ricardo.com/en-GB/What-we-do/Software/P...
find some pictures of a tubi system for your car and copy it is my hounest advice!
I believe its the crank design that tends to give ferrari their unique sound... I suspect your engine is the same, you also need to be careful not to reduce performance as it will need some back pressure and its mid engined so your going to struggle to stop it being loud as length is one of the most effective sound reducers... stick with similar size to original.
It would be useful if you can find out what the original has inside ie if its x trap or just a z trap,
On my V10 M5 I simply removed all the silencers and stuck pipes out the back to see what it would sound/perform like.... the car lost a HUGE amount of power (felt like 80ish BHP) but sounded great... after a few hundred miles the ecu adapted/stopped being so afraid of the change in back pressure and it recovered its power... I liked the sound and so I made some tail pipes that were effectivelly mini silencers (250mm long with half inch of wadding so nothing significant)... these took the edge off of idel but let the engine sound crisp and loud on throttle.
I believe its the crank design that tends to give ferrari their unique sound... I suspect your engine is the same, you also need to be careful not to reduce performance as it will need some back pressure and its mid engined so your going to struggle to stop it being loud as length is one of the most effective sound reducers... stick with similar size to original.
It would be useful if you can find out what the original has inside ie if its x trap or just a z trap,
On my V10 M5 I simply removed all the silencers and stuck pipes out the back to see what it would sound/perform like.... the car lost a HUGE amount of power (felt like 80ish BHP) but sounded great... after a few hundred miles the ecu adapted/stopped being so afraid of the change in back pressure and it recovered its power... I liked the sound and so I made some tail pipes that were effectivelly mini silencers (250mm long with half inch of wadding so nothing significant)... these took the edge off of idel but let the engine sound crisp and loud on throttle.
andygtt said:
find some pictures of a tubi system for your car and copy it is my hounest advice!
I believe its the crank design that tends to give ferrari their unique sound... I suspect your engine is the same, you also need to be careful not to reduce performance as it will need some back pressure and its mid engined so your going to struggle to stop it being loud as length is one of the most effective sound reducers... stick with similar size to original.
It would be useful if you can find out what the original has inside ie if its x trap or just a z trap,
On my V10 M5 I simply removed all the silencers and stuck pipes out the back to see what it would sound/perform like.... the car lost a HUGE amount of power (felt like 80ish BHP) but sounded great... after a few hundred miles the ecu adapted/stopped being so afraid of the change in back pressure and it recovered its power... I liked the sound and so I made some tail pipes that were effectivelly mini silencers (250mm long with half inch of wadding so nothing significant)... these took the edge off of idel but let the engine sound crisp and loud on throttle.
Thanks Andy I believe its the crank design that tends to give ferrari their unique sound... I suspect your engine is the same, you also need to be careful not to reduce performance as it will need some back pressure and its mid engined so your going to struggle to stop it being loud as length is one of the most effective sound reducers... stick with similar size to original.
It would be useful if you can find out what the original has inside ie if its x trap or just a z trap,
On my V10 M5 I simply removed all the silencers and stuck pipes out the back to see what it would sound/perform like.... the car lost a HUGE amount of power (felt like 80ish BHP) but sounded great... after a few hundred miles the ecu adapted/stopped being so afraid of the change in back pressure and it recovered its power... I liked the sound and so I made some tail pipes that were effectivelly mini silencers (250mm long with half inch of wadding so nothing significant)... these took the edge off of idel but let the engine sound crisp and loud on throttle.
The problem there is that the tubi systems are encased, and i cant find a photo of one open...
Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff