what makes the engine tone so different?
Discussion
In the case of the Ferrari sounding different is because of the design.
The Ferrari engine is a 'Flat Plane Crank' (similar to the AJP V8) as opposed to a 'twin plane' classic V8 design
This is taken from the Cerbera FAQ on here
What on earth is a flat-plane crank?
Like most Ferraris, the Cerbera's AJP8 engine uses a flat-plane crank. "Flat-plane" means that the crank throws are all in a single plane - i.e. if you laid the crank on a desk it would be flat. Laying the crank of a conventional (twin-plane) V8 on a desk would result in a very three-dimensional wobbly thing sitting there. In both cases however, the desk will get very oily. With a twin plane you get eight evenly spaced firing intervals for every two complete engine revolutions, but the downside is that you can't take advantage of exhaust pulse extraction effects since the manifold design is prohibitive. The Cerbera's flat plane crank means that the engine (essentially) becomes two four cylinder engines operating on a common crankshaft, so the exhaust design is made like a traditional 4-2-1 set up to take advantage of pulse tuning effects.
Thus a flat-plane crank produces an engine that is more powerful but rougher in nature. It also means that the engine sounds like a pair of four cylinder engines together, rather than the classic "warble" of a V8 (e.g. the Rover engines used in Griffiths and Chimaeras). As a point of useless trivia, a four cylinder engine in a "boxer" configuration, as used by old Alfas, Beetles and of course the Subaru Impreza sounds like a classic V8.
The unusual exhaust sound is made even more weird by the "V" angle not being 90 degrees. Its 75 degree angle means the engine doesn't behave exactly like two four-cylinder engines since instead of the firing intervals being 90 + 90 degrees apart they are 75 + 105 degrees apart.
I bet you didn't really want all that gory detail, did you? And I bet you're now wanting to know what "pulse effects" are? Basically its a technique where exhaust gets actively sucked out of the cylinders by the exhaust system, due to standing waves being set up in the exhaust pipes. Better? I didn't think so....
Other variations in noise on similar designs are down to induction and obviously silencing design and type.
HTH
The Ferrari engine is a 'Flat Plane Crank' (similar to the AJP V8) as opposed to a 'twin plane' classic V8 design
This is taken from the Cerbera FAQ on here
What on earth is a flat-plane crank?
Like most Ferraris, the Cerbera's AJP8 engine uses a flat-plane crank. "Flat-plane" means that the crank throws are all in a single plane - i.e. if you laid the crank on a desk it would be flat. Laying the crank of a conventional (twin-plane) V8 on a desk would result in a very three-dimensional wobbly thing sitting there. In both cases however, the desk will get very oily. With a twin plane you get eight evenly spaced firing intervals for every two complete engine revolutions, but the downside is that you can't take advantage of exhaust pulse extraction effects since the manifold design is prohibitive. The Cerbera's flat plane crank means that the engine (essentially) becomes two four cylinder engines operating on a common crankshaft, so the exhaust design is made like a traditional 4-2-1 set up to take advantage of pulse tuning effects.
Thus a flat-plane crank produces an engine that is more powerful but rougher in nature. It also means that the engine sounds like a pair of four cylinder engines together, rather than the classic "warble" of a V8 (e.g. the Rover engines used in Griffiths and Chimaeras). As a point of useless trivia, a four cylinder engine in a "boxer" configuration, as used by old Alfas, Beetles and of course the Subaru Impreza sounds like a classic V8.
The unusual exhaust sound is made even more weird by the "V" angle not being 90 degrees. Its 75 degree angle means the engine doesn't behave exactly like two four-cylinder engines since instead of the firing intervals being 90 + 90 degrees apart they are 75 + 105 degrees apart.
I bet you didn't really want all that gory detail, did you? And I bet you're now wanting to know what "pulse effects" are? Basically its a technique where exhaust gets actively sucked out of the cylinders by the exhaust system, due to standing waves being set up in the exhaust pipes. Better? I didn't think so....
Other variations in noise on similar designs are down to induction and obviously silencing design and type.
HTH
Edited by V8 GRF on Wednesday 2nd April 16:08
If you could get it to rev to approx 9k+ it would sound pretty impressive,a guy called Steve Green dragged race a Mk1 Cortina in the 80,s with a screaming RV8 TWR sponsored if memory served,eight into one exhaust(no silencing)you had to be there to see this thing launch
that motor must have cost a kings ransom
beat the pants of any Ferrari sound
that motor must have cost a kings ransom beat the pants of any Ferrari soundEdited by That Daddy on Wednesday 2nd April 17:20
V8 GRF said:
The unusual exhaust sound is made even more weird by the "V" angle not being 90 degrees. Its 75 degree angle means the engine doesn't behave exactly like two four-cylinder engines since instead of the firing intervals being 90 + 90 degrees apart they are 75 + 105 degrees apart.
Brilliant, now I understand why I get a fantastic burble and not a "smooth" rumble. Gassing Station | Chimaera | Top of Page | What's New | My Stuff