Optimising Car Performance Modifications: - Simple methods for measuring engine, suspension, brakes and aerodynamic performance gains

by Julian Edgar

Optimising Car Performance Modifications is a highly practical and useful book that covers brilliant techniques to take the guesswork out of performance modification.

Using just some low-cost tools, you can easily measure the flow restriction of your car's intake and exhaust. It's like having a huge flow-bench always available. By making some simple on-road measurements, you can plot the shape of the engine's power and torque curves - no dyno needed. This allows you to not only see if performance modifications to the engine are improving power, but also see where in the rev range those changes are occurring. Assess the worth of cams, a larger turbo, changed boost control or altered engine management mapping.

But the book doesn't stop there - it also shows you how to measure your car's aerodynamics, seeing if at speed your car is developing lift or downforce. Want to make a rear wing work well? Test the angle at which downforce is greatest. You can also test the aerodynamic airflow through oil coolers, intercoolers and radiators.

Interested in improving your suspension? By using a low-cost app and a smartphone, you can accurately measure suspension behaviour.

If you want a practical, hands-on book that will immediately save you money, show where modifications are most needed, and can be used to assess performance outcomes, this is the book for you.

72 pages, Paperback

Published August 15, 2018

About the author

Julian Edgar, 56, started his working life freelancing for photography magazines. He then worked as a secondary school teacher for eight years before leaving teaching and becoming a full-time technical writer.

He edited a national Australian automotive print magazine before becoming editor of an online car magazine. Along the way he wrote extensively for electronics hobbyist magazines while also contributing articles to publications in Australia, the UK and the US.

He has also worked at Executive Level in the Australian Public Service. Formal qualifications include a Diploma in Teaching (Secondary), Bachelor of Education and Graduate Diploma in Journalism.

In the automotive field he has owned cars with two, three, four, five, six and eight cylinder engines; diesel, petrol and hybrid petrol/electric drivelines; front-wheel drive, rear-wheel drive and all-wheel drive configurations; and cars with single turbos, twin turbos and superchargers.

He has been electronically modifying his cars for about 30 years. Over that time he has modified engine management systems, engine cooling systems, turbo boost controls, electric power steering systems, auto transmission controls, all-wheel drive torque split controls, stability controls, hybrid car regenerative braking controls, and lighting and sound systems.

He also enjoys aerodynamic modification of cars. He was the first automotive journalist to extensively wool tuft cars and write about the results (starting in 1989), and use Magnehelic gauges to directly measure aerodynamic pressures (in 2000) - both approaches now widely used by amateurs. In 2018 he developed a technique allowing amateurs to measure car aerodynamic panel pressures on the road.

Julian has supercharged - and then turbocharged - a Toyota Prius. He has also turbocharged a Honda Insight and fitted it with programmable engine management, doing the engine mapping from scratch. The Insight also has electronically-controlled, custom air suspension that Julian developed and fitted.

He has an extensive home workshop that is equipped with a chassis dyno; lathe; mill; MIG, TIG and oxy welding gear; metal folder and other tools.

Julian lives in a hamlet 80 kilometres north of Canberra, Australia. He is married to Georgina and they have a son, Alexander, who is 16 years old. Also in the family are Victor the sheep and Ar-Chee the cat!