Turning Ambruosi into a Winner

Marshall Custom Camshafts

Turning Ambruosi into a Winner

 Johnny Marshall, the driving force behind Marshall Custom Cams, has been instrumental in the careers of many Australian top alcohol racers.

Robert Ambruosi is one such client.

Ambruosi was mentored under John during his TAFE years, while JM taught mechanics at the school.

He went on to create Robert Ambruosi Motorsports, racing on the circuit for 10 years now.

This past weekend, in May 2016, Ambruosi’s car lit up the track at Sydney Nitro Champs, taking out the silver Christmas tree.  He also clocked up the second fastest qualifying time of the weekend.


Johnny is the absolute leader in camshaft manufacturing. Nobody gives you the vast knowledge and experience. His methods are the best, and his camshafts are the best. My team wouldn’t race as well as we do without Johnny’s expertise… We have tried rest, now we use the best!


Performance increase with a Marshall Custom Camshaft

Prior to using a custom cam, the Ambrosi car would only rev up to 9,200 RPMs and then have valve train component failures; after fitting a custom camshaft produced by MCC, the car comfortably pushes out to 10,800 RPMs without ANY valve train issues.  Increases like this are where you’ll pickup the half second on your quarter mile times.  Additionally, Ambruosi’s team have far less maintenance to perform after each pass,  with the more stable valve train and much less harmonics produced by the custom camshaft.

Has Ambrosi come back to us for further work?

Rob also runs his own shop, building high performance engines.  After the successes of the cam in his top alcohol funny car, Marshall Custom Cams now provides all of the camshafts for Ambruosi’s shop-built engines.

What is it that inspired Johnny Marshall to produced cams for these Alcohol race cars?

A lifetime of racing and experience is the key here.

Spending many years working on cars and race teams around the track, JM realised that the camshaft was the ‘lungs’ of the engine.  And specifically, high-performance engines need their lungs to operate smoothly in order to reduce the deadly valve train harmonics, which was not the case with most of these vehicles.  Knowing that a perfectly smooth cam could solve many problems led JM to strive to produce the perfect, Smooth Lobe camshaft, that now powers team such as Robert Ambruosi motorsports.