Induction Kits

[JQ]

Just out of interest, do induction kits such as K&N actually improve performance? If so, what kind of difference do they make? Are there any other benefits?

[OllieWinchester]

Main benefit = the noise.

A lot of people say they won't create any more power, but I think that's largely because on a dyno they don't get the ram air effect you'd get on the road.

The Jackson Racing intake has been proven to give more power, but apparently they're expensive, and they don't make them anymore.

[Daaave]

Do they actually make that much more noise? I still have dreams about my mates old M3 induction roar

[GravelBen]

A lot of cheap 'induction kits' are more likely to lose power as they suck hot air from the engine bay rather than cold air from outside. A proper cold air intake might see a small gain in power.

[Mannginger]

Daaave said:

Do they actually make that much more noise? I still have dreams about my mates old M3 induction roar

I put one on my old Fiesta ST (K&N 57i). No powers gains to speak of and as mentioned above, it was probably slightly less on a hot day but the noise it made had me grinning from ear to ear.

It suited the (slightly chavvy) nature of the ST but I don't think I'll put on on the MX5 (maybe a panel filter but that gives you no noise improvement). I am hankering after a new exhaust for the '5 though...

[Evangelion]

Would one of those vented light covers get enough cold air into the engine bay to make a difference?

[Quick silver]

Mine came with a K&N as fitted when imported........I have since added cold air induction.

The noisiest/sweetest sounding induction I have heard was on a friend's, son's Corsa sri......I believe it was a Pipercross filter that looked nothing more than a black sponge in a wire frame. but it sounded excellent when pulling away.

[nfo]

Don't bother with a K+N type panel filter, all it'll give you is more fine rubbish going into the engine. Have a look here:
http://autospeed.com/cms/title_FreeFlowing-a-Miata...
http://autospeed.com/cms/A_111396/article.html

7% of the total pressure drop in the inlet system was due to the filter element. When I had a Focus, I found out that the standard paper air filter was the same on everything from the 75bhp 1.4 to the 170bhp ST170. That should tell you everything you need to know about replacing panel filters.

The K+N Typhoon kit has about a million 5* reviews on MX5parts for its sound, if that's what you're after.

[JQ]

nfo said:

The K+N Typhoon kit has about a million 5* reviews on MX5parts for its sound, if that's what you're after.

Wow, just checked out those reviews - people absolutley love it. Very, very tempted.

[OllieWinchester]

GravelBen said:

A lot of cheap 'induction kits' are more likely to lose power as they suck hot air from the engine bay rather than cold air from outside. A proper cold air intake might see a small gain in power.

See my first post. This is IMO a misconception due to cars with these sort of filters showing less power when on a dyno, when they will be almost exclusively sucking hot air from the static engine bay. The same will apply in traffic, but once you are underway its a different story. Thos fans cannot replicate the ram air effect you get when the car is underway.