Bimota Forum

[stockcar]

OK so that'll be why F1 cars have drain pipes fitted NOT..................

there is a physical limit on the size of the pipe to enable power to be made on a 4stroke, have done some testing with a turbo motor before and lost 30bhp at peak and around 50fl/lbs on a 400bhp engine by substituting the "relatively" restrictive back box with a straight trho pipe the customer had had made and insisted he wanted fitting (it also moved the spool point up the rev range by approx 1500rpm!!)

[2bims]

Yeh but did it sound better

[stockcar]

it sounded "awesome", was measured at around 115db at IDLE.............

just drove absolutley shoite...........

[Vince186]

[stockcar]

it was on a turbo engine, so the "spool" point is the RPM it starts to make boost (spool up)

[oily]

And to be fair..........
a huge TURBO engine and a relatively small, underpowered ( ) NA engine have totally different characteristics and require totally different exhaust science

.....but they both need to be LOUD
_________________
SB6 mk1 (project mega light, big bore)
Sb6 mk2 ( Big Bore)
Sb6 mk2 ( Restored)
Sb6R fighter
Sb6 or Sb7 WANTED

[mainstone41]

Loud is goooood!

[husson73]

[stockcar]

[CBar]

My silencers were highly restrictive. This is the 1st thing the exhaust hit.


Then it goes through 3 stages.


Exiting through this.


I was after a some noise, but not LOUD LOUD. I wanted to keep my mid-range for the street. I bought some 1.5" baffles, cut them lengthwise, and tapered them down to match the stock exits. I'm very happy with the results.

Here's a piece of the baffle I used.

[mainstone41]

Interesting to see whats in there, cheers for pics!