Hi List members
I've been scouring this list for some time now and have found that it
contains very little information (if any!) relating to hydraulic roller cams
that can be used with the Buick/Rover alloy V8 (or its derivatives). This
seems a little strange (if they are, in fact available), as I would suspect
that this is definately an area that would be of concern to the performance
enhancement for these engines - especially the bigger capacity variants of
these motors that are close to 5.0L. High flow heads for these motors are
horrendously expensive (approx. $2000.00 in Oz anyway) and there aren't too
many good porting shops with expertise knowledge in this area either. The
final product would probably cost almost as much as a set of new high-flow
heads anyway - especially to get close to the flow numbers of Buick 300
heads. So how can you make these motors perform without taking out a second
mortgage on your house?.......
Enter roller cams..... Roller cams allow a larger volume of intake charge to
enter the cylinders when utilising standard cylinder head ports, relying on
the faster opening ramps of the cam design (usually at a higher valve lift),
all this adding up to improved performance. The Australian Commodore V6
(Buick variant) is one such engine which benefits enormously from the
advantages of an OEM hydraulic roller camshaft - having an almost flat
torque curve throughout the entire rev range, resulting in a very tractable
engine. A high capacity Buick/Rover V8 however, has very good low end torque
but dissapointing top-end power due to standard heads inability to flow
sufficiently for the increased engine capacity. A hydraulic roller cam could
compensate for this by increasing the flow but not necessarily the cam
duration, resulting in a flexable engine throughout the operational rev
range with good idle characteristics. Sound too good to be true? Believe it!
It appears that instead of relying on a possibly suspect porting job, or
purchasing a pair of expensive heads, there could be another more reliable
cost effective alternative. I'm certainly not saying that a hydraulic roller
cam alone will be sufficient to achieve all the breathing requirements of a
high capacity engine - but it would certainly come close. After all, nearly
all current performance OEM engines with pushrods use roller cams nowdays.
As there is also a need to develop larger capacity versions of the
Buick/Rover V8, there would also be a requirement to overcome the standard
engine's breathing limitations without resorting to high dollar techniques
like turbocharging and supercharging.
......and finally to my questions: Is there a hydraulic roller cam available
for the Buick/Rover V8? Who is the supplier and at what cost? Can one of
these cams be fitted to this motor or are the modifications required to the
block too extensive (i.e. lifter gallery oil passages)? Can the lifters,
retaining plates etc. from the Buick 3.8L V6 (late 80's) be adapted to fit?
Remember - the lifters from the old Buick V6 will fit the V8 (I heard that
somewhere!) and if that's the case, what mods were done to the Buick V6
block to fit the roller cam and lifters. Since the V6 block is (or was)
basically cast in the same mould as the V8 (minus 2 cylinders), can the same
mods be applied to the V8 to fit the roller cam and lifters?
Mmmmmm - I wonder if the Shadow knows?
Paul Rakich
Rover SD1 V8 SE2
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