Early in testing the Astra J VXR it was discovered that the original factory airbox simply would not cut it even with the usual modifications. Porting it simply could not flow the required air, so some kind of induction system was required.
During initial induction testing it soon became apparent that a straight/parallel air MAF housing not unlike the Astra H 80mm MAF with a cone filter simply clamped on the end was not the answer. This parallel design created too much turbulence from the air turning from the sides of the filter into the housing and due to the lack of available space between the air filter and the MAF metering head, even with the addition of an air straightener, would not clean this turbulent air. The result was a restriction of air flow along the inside edges of the MAF and thus the air was
accelerated through the center of the MAF which in effect meant the engine was receiving less air than the mass meter was reading and reporting to the ECU. The target was therefore to create a trumpet with as long and smooth a progression of taper as space would allow in order to slowly turn and progress the air so smoothly that an air straightener was not even required. After testing a number of prototypes we achieved this goal.
Now we had to produce this. We looked at aluminium, however this was deemed too heavy with far too much wastage having the units moulded would make the product far too expensive so we turned to the relatively new dark art of plastic printing. We are able to make both the trumpet and the housing in one piece making it very clean looking on the outside and smoother for flow on the inside with a weight saving over an alloy version of a fraction under ½ a kilo. Not massive agreed but it all counts.
Attached to the new MAF housing we use a massive high flow AEM dry filter for very efficient filtration and breathing. This package is then housed in a powder coated heatshield assembly with the Courtenay Sport logo laser cut out of it.
So what does it do?
With the standard inlet air pipe just over 13bhp at peak power and with an enlarged silicone induction pipe 15 BHP. Also when compared to a parallel housing induction version it makes an extra 3 BHP at peak and a further 15 BHP from 5650 RPM! The MaxAir induction system is compatible for both mapped and standard cars.
CSR MaxAir Intake System £249 Silicone Inlet Hose (shown in blue) also available