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998 155bhp FastPhil
Phill was a
previous Japanese bike owner. He decided to purchase a Ducati
998 which he liked very much but was dissatisfied with the straight line
performance compared to his old gsxr.
Phill had his heart
set on getting 150 hp from the 998s with big midrange power. After a
long chat at the CJS workshop Chris said he could make this possible.
In order to get this
sort of power from a 998 and keep the engine reliable the engine had to
be blueprinted using a balanced crankshaft/flywheel assembly with pankil
conrods and pistol 13.1 pistons. The crankshaft balance is critical for
high rpm smoothness and prolongs engine life.
As
usual the bottom end was shimmed to spec assembled with squish set to
the optimum but safe distance for 11.000rpm use.
In
standard trim the cylinder heads are only good for 139hp with a big
exhaust . To reach 150hp it needed serious revision especially to the
short side radius, throat size and valve angles. Chris re-worked the
ports on the flow bench to make the desired shape and installed 2mm
larger flat nail intake valves using the PEG multi angle seat cutter.
Chris knew Phil was a member of the DSC and many people would get
to hear about the project so he ran several more than usual flow tests to
establish a better valve and seat combination for more airflow and power
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The new port shape with colsibro race guides. |
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New combustion chamber shape with oversize inlet valves. |
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The
new re-worked heads were shimmed using the standard cams which were degree'd to a tried and tested spec to boost the midrange power.
After
the engine was installed a full 57mm Leovince exhaust
system was added along with a powercommander 3.
On
dyno day we all smiled and jumped around as the bike made 150hp on its
first run .
DYNO CHART click image to enlarge
People ask how reliable a 155hp tune would be.
This engine is now stronger and more reliable then Ducati ever made
it . The peak power is produced at a lower rpm than originally
intended prolonging service, valve and rocker life !!
