Flugelhorn Two -
The Resonator !
on from the initial testing of tuned pipe lengths on an MG ZR, comes, hot off
Flugelhorn Two - The Resonator.
Although somewhat tongue in cheek, we wanted to try a smaller diameter tube
to see what
the effects on maximum bhp would be.
bhp was 86 at the wheels
with marked resonance at around
3000 rpm and at 6000 rpm.
next test involved a 90 degree tube fitted half way
along the 'pipe'.
Bhp was 85 at the wheels with powerful resonance in the
'offshoot' tube at around 5000 rpm and slightly less powerful
resonance in the 'pipe' at 6000 rpm.
Stage three involved capping the 'offshoot' tube to allow it to
act as an idler branch resonator. This reduced the resonance
at 5000 rpm to an acceptable level, but made no difference
'offshoot' tube can be seen in the
picture to the left and in the picture
The picture below captures a pair of
snails dwelling 'neath the rear spoiler
of the ZR .....slow car or what?
return to our Home Page.
have had a few e-mails asking why the tuned
length/K&N set-ups seemed to lose out at max bhp
rpm compared with the Factory set-up.
In a nutshell, each part of the induction system resonates
at a particular frequency...the valve to plenum chamber length
is important for mid-range grunt, the plenum chamber acts as
a Helmholtz resonator and does its own thing at a specific rpm,
as does the throttle body to air filter pipe.
All three together, if matched, will enhance maximum bhp,
as is the case with the Factory lengths and volumes.
We lost bhp when we altered the throttle body to air
The moral of the story....beware the fitment of separate
throttle bodies on short inlet pipes...'it' may not happen
for you as you might hope!!!!