Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGF Technical - Air box and filter - improve the breathing

I have a 2001 VVC with the bigger airbox and filter. After a closer look i've noticed however that i doesn't breathe much better than the older setup because the feeder pipe is still at the rear of the engine bay.

I was thinking that, without buying a KN, Maxogen or Pipercross, I could greatly improve the breathing by running a pipe from the side vent into the standard filter (I would have to cut a hole in it though, on the lower front part). And maybe change the paper filter for a "ramair" or similar.

Has anybody tried this? It would be ascaled-down version of Carl from Sweden's excellent system as depicted on Dieter's site.

Anthony Braham

Have a look at the Lotus site archives (you are logged in with the same ID) for pictures of how they modified the standard airbox to take a bigger feed hose and relocation.
Will Munns

That's a good idea Anthony - basically what Roger and Bruno pioneered a few years back (Bruno's power curves can be seen at

The new air intake is certainly better than the old, primarily because the intake length is shorter, and doesn't have to travel though so many angles!
The reason for the air intake down at the rear of the engine bay is because this is, in fact, the coolest area (according to measurements made by Paul Sharpe). But using the nearside intake is better still IMO.
You'll struggle to get a 100 mm tube to fit though (if you slavishly follow the Lotus pattern) - there simply isn't enough room to feed the pipe to the intake. You may find a realistic limit at around 70-80mm.

I took a similar approach with my Rover 820 airbox mod:

Have fun - and let us know how you get on! :o)
Rob Bell

Thanks for the info, gentlemen.

Rob, I had seen the picture of your Rover airbox page but not the "pix of installation", which are excellent (because they show the path of the air duct). Did you use 80 or 100mm pipe diameter?

I would rather go for the Rover airbox than savage my original airbox but the chances of finding one in Switzerland are remote because Rovers, whatever the model, are few and far between. However I don't want too much noise - how much noise does the conic filter/Rover airbox combination make?

Ideally I'd also like to force the air into the side vent in some way or other. Carl's plexiglass "wing" looks good for that purpose (doesn't spoil the aesthetics too much either).
Anthony Braham

Anthony, the orange ducting you see in the pictures is 70 mm in diameter - which is perhaps a little smaller than is desirable, but fits like a glove into the space available (especially as my '96 MGF still has its resonance box in place!)

No real need to go for a 820 airbox in particular - the design is shared with a number of other Rover models, including the Maestro and Montego!

Other manufacturer's airboxes would probably do the trick too - I seem to recall someone saying that a Fiat airbox is similar? Perhaps a jaunt to a scrap yard is in order?

Noise wise, the new filter arrangement is much more subdued than an exposed cone filter - much more refined. So it probably fits the bill in your case.

Regarding cone options, I've used a K&N 57i, although almost any cone filter can be accomodated, and if you modify my set up, you could even use a replacement cylinder filter for the airbox you eventually decide to use :o)

Carl's little 'winglet' looks brilliant - I haven't tried that yet - but it is on the 'to do' list ;o)
Rob Bell

Thanks for the information and advice Rob.

And let me know when you start work on a winglet (i'll do likewise) :-)
Anthony Braham

I'll think I'll do as Carl has done and buy a 'spare' engine inlet grille, Anthony :o)

Good luck! :o)
Rob Bell

This thread was discussed between 20/03/2003 and 21/03/2003

MG MGF Technical index

This thread is from the archive. The Live MG MGF Technical BBS is active now.