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We now manufacture our own design of easily adjustable CVH solid lifters that
are matched to a range of specially ground camshafts, for normally aspirated and
turbo engines from fast road up to full race.
The use of solid lifters in place of the factory hydraulic items is common to
most types of performance engine and is generally regarded as an essential step
in the process of engine development. Extensively tested in road and race
conditions, this solid lifter cam kit has provided excellent and reliable
results. The key feature of these lifters is the shim
that sits on top. Although this means
that they take more time to set-up initially,
the shim acts as a "spinner" that allows the follower
to rotate freely while running. The main reasons for using a solid instead of hydraulic lifter are:
1 - High rev reliability. At high engine speeds hydraulic
lifters interfere with valve operation and account for the sudden and dramatic
drop in power build up at a little over 6000 rpm. Look at any power graph for a
CVH and see how strongly the curve climbs before drop-off occurs, then imagine
projecting the power line at the same rate of climb for another 1000 rpm! A
thousand extra revs may not sound like a lot, but even with a fairly standard
road car the extra power generated can be quite significant.
Mark Stanton, Chairman of the Westfield Sports Car Club provided the figures
for the power graph below once he had fitted a Ferriday cylinder head assembly
with solid lifters. (Full spec sheet - here)
1600 CVH Westfield road & sprint car
belongs to Mark Stanton. Standard bottom end with Ferriday modified head
& Solid Lifter Cam Kit, 10:1CR, twin 40's. Rolling road figures
supplied by Hi-Tech Motorsport, WestMidlands
2 - Positive Valve Opening. Even at lower revs a hydraulically
operated valve suffers from a “soft and soggy” opening operation. By
replacing this with a positive mechanical lift, a more precise motion is
achieved. This leads to a faster change in manifold vacuum, greater gas speed
and ……...more power!
3 - Predictable Operation. Hydraulic lifters are subjected to
large and frequent variations in oil pressure and temperature. Solid lifters are
a known quantity that simplify valve operation and remove such variables.
4 - Weight and friction reduction. A solid lifter is 10%
lighter than it's hydraulic counterpart, and given the overall weight of CVH
valve train, this is an important bonus. Any loss of weight in this area will
help with engine efficiency and life expectancy. Also, a hydraulic lifter exerts
a constant pressure to the total circumference of each lobe base circle
resulting in a certain amount of drag. A solid lifter does not contact the
camshaft base circle, so internal friction is reduced.
A full cam kit consists of - 1 camshaft (choice of profile), 8 solid lifters,
8 valve springs, 1 timing disc, & 1 tube of camlube. Price for this kit is
£330.00 total. Fitting instructions are supplied, and technical help by phone
is also available. A range of commonly used cam profiles are kept ex-stock, but
specially ground profiles to suit individual needs are available at the same
price.
Please note - solid lifters are not compatible with hydraulic
camshafts.
Performance Ford Cologne Cylinder Heads |