Ferrari 3.0L V8 - muffler positioning, and x-flow for specific sound

Question

I am re-designing a Ferrari exhaust system with 2 objectives:

1: enhance the specific high pitch raspy sound that you expect from a small Ferrari V8.

2: achieve a good free-flow design.

There is approx 1.5m of tubing between the header and the tail pipe, where along this should I place a silencer in order to get the best raspy tone? Does this make a difference anyway?

There are 2 headers, would there be any advantage to using some sort of x-piece? and how will the use of that (and indeed the size of its x-flow port) effect the sound?

Background:

The car is an old 3.0L V8, and the factory exhaust has had it - factory replacements are not available and after market ones are ridiculous money.

The exhaust on it isn't very loud, and doesn't really do justice to the engine, as more recent cars with the same basic block sound MUCH better.

Answer 1

Ferrari V8's have flat-plane crankshafts, which should already give yours a very distinctive exhaust note that I believe is what you're referring to as "rasp".

As such, I don't think a cross-pipe is necessary to improve sound quality.

If your concern pertains to the lack of volume, it can be remedied with use of mufflers that don't suppress sound as much (or no mufflers at all, if you're into that sort of thing).

If you want to enhance a certain frequency of the exhaust note, the dimensions of the exhaust plumbing and silencer/resonator/muffler placement will influence the end result.

For more information, you can refer to Scientific Design of Exhaust and Intake Systems (Engineering and Performance), a well-respected book on this topic.

Answer 2

As you are in the UK, try someone like www.simonscustomexhausts.co.uk/‎. At the least they will keep you on the straight and narrow. As you will know vehicles used in the UK will fail an MOT inspection and be prohibited for use on the Queens highway if:

1. An exhaust system is not adequately supported.

2. Has a major leak of exhaust gases from any part of the system.

3. A catalytic converter missing where one was fitted as standard.

4. A silencer in such condition, or of such a type,that the noise emitted from the vehicle is clearly unreasonably above the level expected from a similar vehicle with a standard silencer in average condition.(Source- VOSA MOT manual)

Another point to bear in mind is that if you change the exhaust you can seriously affect the engine temperatures and performance. If the gas flow is restricted from an exhaust fitment, catalytic convertors and silencers may be irrepairably damaged. A further point is the vehicle is described as 'an old V8 Ferrari'. Modifications and adaptions from the factory specification would quite possibly wipe thousands of pounds of off its value, especially when you think even a new factory fresh Ferrari would be regarded by most as a classic.