Race Engine Forum UK

Hello Guy,

There's a while...

In the attached file you can find some simple drawings showing my actual intake (slide 1 & 2). The filter (ITG) is mounted on a plate at the end of the horns and this in the engine bay. Even if the duct of the Montecarlo brings air from the front I think the air can be cooler (more cool ?) if I use an airbox with a hose directly in the tunel coming from the front.

My 1rst question is : what's the best solution, the airbox around the existing filter (slide 3) or another filter in the bottom of the box (slide 4) ? In this case I'm afraid that the filter "slow down" the air (???)

My 2nd question is : are there rules to calculate the volume of the box, the diametre of the intake of the box, the lenght of the hose ... May be a good article coming from you for the forum. I let you decide of course.

Thank you in advance and best regards,

Robert

Option 3 or 4 would be my choice. Noting that:

1. The airbox must allow access to clean/change the filter
2. The volume of the airbox should be sufficient to give 2" around the filter in all planes and the filter must not be clamped right over the rampipe - it must have a standoff of at least 1" all round. yes, the airbox will be quite roomy.
3. The duct to the airbox must draw air ambient not the engine bay - the latter can cause detonation in that car
4. The trunking must be as big as possible to minimise pressure drop. I recommend 4" ID.
5. Airboxes are subject to extremely degrading vibration. They need to be either extremely rigid (= heavy) or light and flexible. Internal fasteners - choose carefully. Any loose part will be ingested instantly.

It can be better to duct from under the vehicle to a remote cylindrical filter (the original MC had such a filter canister, maybe partly cylonic, not sure) and then up to the airbox. This makes filter maintenance easier and reduces the size of the airbox.

I hope that helps some,

G