Let’s get the bad news out of the way right up
front. Firstly, despite being the most recent editions, both of these books are
very dated – they could have been written 20 years ago. Secondly, each is a very
small book (about 60 pages) and so any coverage of as complex a topic as
camshafts or ignition timing must be superficial, adopt rules of thumb and
concentrate on what the author sees as the mainstream of engine modification.
The results will be frustrating to someone wanting
to really understand the modification of modern engines, is working with a
turbocharged or supercharged engine, needs to meet emissions legislation, or has
to deal with concepts like variable cam timing.
However, if you want an easy to understand basic
primer in each of these areas, the two books are good. In a way, it’s a bit like
first learning about engines by pulling apart a 4-stroke lawnmower – the
complexity will differ from a car engine but the basic concepts will be much the
same.
Both books are in full colour.
How to Build and Power Tune Distributor-Type
Ignition Systems
As the name suggests, if your car uses direct fire
ignition, this book is not for you! Well, that’s not actually true – if you have
fully programmable ignition timing control (eg through the use of an aftermarket
engine management ECU), there’s quite a lot of information that will be of
peripheral use. But it’s those owning cars featuring dizzies with centrifugal
and vacuum advance mechanisms that will benefit most.
There are 12 chapters in the book but some are
less than two pages long. Many of the chapter headings are self-explanatory, for
example:
- Modified Engines Need More Static/Idle Speed
Advance
- Estimating Total Advance Settings
- Vacuum Advance
- Ignition Timing Marks
- Altering the Rate of Mechanical Advance
With distributors, the static (and usually) idle
advance can be set by just turning the distributor, so the book covers selecting
the appropriate timing, taking into account primarily the cam specs. The advice
is practical and down to earth. Modifying distributors to alter the rate of
advance and the total advance is detailed, along with some rules of thumb for
correlating combustion chamber design and ignition timing. However, there aren’t
any dyno graphs showing the results of such changes and - in parts - the book is
rather simplistic. No mention is made of wiring-in aftermarket transistor
assisted ignition systems (let alone CDI) or of converting points systems to
Hall Effect or optical triggers.
In summary: a decent book for someone with a
points-and-dizzy car who wants a quick overview of some DIY, non-electronic
modification techniques.
How to Choose Camshafts and Time Them For
Maximum Power
Again, this is a book that couldn’t have been
written 20 – or more – years ago. The nine chapters include:
- Terminology (a good chapter on camshaft
basics)
- Choosing the Right Amount of Duration (not so
good: rules of thumb applied, no dyno graphs showing different results, no
mention of emissions or anything like that, no specifics on any engines)
- Checking Camshafts (short but useful)
- Camshaft Timing – three chapters (good primers
on the basics of setting up cams)
- Camshaft Problems (useful)
- Engine Testing (poor)
If you want to know how camshafts function in
terms of engine airflows, this book isn’t really for you. (In fact, the
documentation that comes with engine simulation software programs is often
better on this topic.) It’s also pretty unhelpful if you’re dealing with an
engine managed engine and want to (say) work out an optimal overlap taking into
account the effects of a tuned-length intake system and the ability to alter
injector timing.
But if you’ve just bought a cam and want to
install it in your pushrod, SOHC or DOHC engine, this will be a useful book –
especially if read in conjunction with a good workshop manual for the car being
worked upon.
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How
to Build and Power Tune Distributor-Type Ignition Systems, Des Hammill,
Veloce Publishing, ISBN 1-903706-91-2, www.veloce.co.uk
How
to Choose Camshafts and Time Them For Maximum Power, Des Hammill, Veloce
Publishing, ISBN 1-903706-59-9, www.veloce.co.uk
Review
copies provided gratis by the publisher
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