Fiat 124 Spider - Camshafts

FIAT 124 Spider
Engine Maintenance + Modification
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11.1.5 Camshafts
The camshafts installed on the 124 Spider are designed for normal road use. They
provide reasonable performance and are very durable. Other camshaft profiles are
available for the Spider, ranging from “street” to “hot street” to “racing.” If you are
considering camshaft replacement you should speak to people who have done this
before and understand the sacrifices of changing cams, such as:
• fuel economy may be reduced;
• idle and low speed operational quality may be reduced;
• acceleration may be undesirably jumpy; and,
• it may be impossible to pass emissions testing.
Understand that the camshaft is the engine’s brain. Changing that brain can result in a
very different engine. This operation may be very good or very poor for your conditions.
The stock cams are reliable, inexpensive, and do not significantly reduce street
performance. If you are considering camshaft changes visit someone with a modified
Spider and drive it, see if you like the overall operation.
It is important to check that your camshafts are in good operating condition and are not
worn. Measure or have the camshafts measured to the spec in your shop manual and, if
necessary, replace them. Stock and aftermarket camshafts are available from parts
vendors.
If you are new to the 124 Spider or just now considering engine changes, there are
stories all over the internet about the European specification 1608 camshaft having a
“better” profile than the later years. A few years ago Allen Lofland, a FIAT and Lancia
owner, led a crusade to prove this myth. Several people (myself included) bought
camshafts from the European 1608 Spiders. I bought my set right out of a car while
living in Europe – so I’m fairly certain of the originality. The cams were studied,
measured, inverted, turned, shaken, installed, driven, and…you probably guessed
already – it is a myth. The only notable difference in the USA and European 1608 Spider
was the installation of one (USA) or two (Europe) carburetors. Certainly there is room for
error, and these mythical camshafts may have existed, but we couldn’t find any.
11.1.6 Camshaft Wheels
The cast iron camshaft wheels are extremely durable but very heavy. Heavy engine
components will rob some power from the motor. Some of the camshaft wheels are
made of industrial-grade plastic, very light but lacked durability. In both cases there is
room for improvement. Later model FIAT wheels are slightly lighter as they have a hub-
and-spoke construction (they are still iron). Aftermarket wheels can be had in very
lightweight aluminum.