Air Filters

Air Filters, what a nightmare to get them on the car. The problem on this car is that it was designed around the old, leaded engine which runs quite cooler than the unleaded conversion I have. The required unleaded modifications carried out prior to me purchasing the car meant the SU’s were pushed further out (due to the inclusion of the a heat-shield and spacers) so while the carbs fit, and air-filtration simply won’t in standard form. I’ve looked at lots of different filters from ITG, K&N and PiperCross along with various others and always hit the same flaw – there simply isn’t room to install them without body modification.

The above picture shows the space the car had but no distances are given. As an scale consider that the front carb leading edge is 35mm from the edge of the body, less when you consider the bonnet curve, the engine wobble and so forth. That’s not a lot of room.

There are five alternatives:

* Modify the bodwork
* Make a custom airbox
* Install a single carb & suitable manifold
* Use thinner (MGA or Mini) spacers which push the carbs closer to the engine.
* Not worry about it

Obviously not worrying about isn’t advised, changing to a single carb is advantageous (no balancing to do) but with later engine modifications it wouldn’t be able to deliver the air-flow required and putting the carbs nearer the engine isn’t all that a great idea either. That leaves two options modify the bodywork or make a custom air-box.

In the end I installed a small scoop on to the side of the car, but on the way to that decision I did some research into making an air-box & the requirements to ensure maximum air-flow. This is available here.