Hi folks
I have a Rover 3500 P6 1970 model with a Rover 3,5 litre V8 mated to a 5
speed gearbox from the Rover SD1.
Of course, like everybody else, Im looking for more power without paying to
much for it.
A 4,6 litre Rover engine is still too expensive for me, but one day....
My engine consist of a bottom end from a P6 Rover with 10,5:1 CR, and SD1
heads (the SD1 heads have slightly bigger valves and even slighter improved
ports compared to the P6 heads). The SD1 heads also have slightly bigger
combustion-chambers than the pre-1976 P6 heads, which reduces the CR. by
0,25. So my engine should have about 10,25:1 CR. I have also been very
carefull to match the ports from the intakemanifold to the ports in the
heads. I have installed "Luminition" electronic ignition, and replaced the
original cooling fan with an electric one. The engine runs with standard
SU-carbs.
All this blueprinting have made the car very economic to drive: (8-9 litres
in 100 km). Very important in Norway where we have the higest fuelprices in
the world!!
The engine pulls without hesitation and not bad already from 5-600 rpm` in
5th., which ensures a much relaxed drive. The engine also revs willingly
and smoothly to 5500 rpm`s without the power dropping of noticeably.
But I want more......
I understand that in order to gain much power, the breathing of the engine
must be improved. This could of course be done with another intake with 4
bbl carb of some sort, and another camshaft.
Since this is a classic car, I would like to keep an original apearance of
the engine and retain the SU-carbs. This leaves me with a change of camshaft.
My question therefore is: is there a camshaft that will give more mid- and
top end power without sacrificing to much at the bottom? Does anybody have
experience with such an after market camshaft?
I have already tried the "Crane HI 216" with the matching fast bleed down
lifters. This set up was a real disapointment for me because the bottom end
power suffered too badly, and those spesial lifters were VERY noisy! This
camshaft woud have been a good thing for somebody who keeps the rev`s up
most of the time. I myself spend much of the driving in the range between
800-1800rpm`s. So the power down here is very important for me. Is there a
camshaft that will not sacrifice to much of this delight, and still give
more than the standard shaft in the mid to high rev-range?
After all, the standard camshaft was desingned in the 1960`s, and this is
almost year 2000! One should believe there have been a development over the
last 30 years?
If you have any tip about camshafts or anything else in cheap powergains, I
would be grateful.
Thank you
Eirik Aarebrot
Stavanger, NORWAY
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