Which air filter

[GlennyGills]

I recently added a MX5Parts Stainless exhaust, which was a bit louder than expected, so I removed the Cone filter to reduce overall noise. I re-fitted the original air box with a cheap air filter. However, there is a perceived power loss since the replacement. My question: Are the performance air filter that fit within the std air box any real benefit or should I just go back to the Cone?
Has anyone got any experience with these costly performance filters (non-cone)?

Thanks

[71notout]

A lot of folk claim that the standard airbox design (on a Mk1 at least) is the best in terms of performance.

Some folk run with that and standard filter, others run with that and a drop-in K&N.

I have just junked mine to fit a cone filter as I love the induction roar - I know all about heatsoak and possible losses in performance but let's be honest, in standard trim, these aren't exactly tarmac ripping machines anyway are they?

If you can source an ARC Chamber from a jap import, they get good rep, or a Jackson Racing setup which pulls air from the front of the slam panel and (I believe) directs it into the standard setup?

I am contemplating adding a Randall Cowl setup that involves cutting a hole in the flange above the firewall and adding some piping that takes cold air from the high pressure area there and directing it towards the cone filter but I am still contemplating it all.

I do run a small heatshield around my cone filter as well but as to how effective it will be...

[storm]

If you are looking to drop in a panel filter, I HIGHLY recommend a multi density foam panel as it is by far the most efficient at filtering particles as well as air flow. The paper and cotton gauze ones are only as efficient as the largest hole in them. Oiled cotton filters tend to get over-oiled by the users and end up sending too much oil/oil vapour through the intake manifold and end up gunking everything up. Million mile warranty or not, you'll need more frequent oil changes due to the amount of contaminants making their way into the engine.

Cone filters make a great induction noise but - as mentioned above - they generally suck hot air and don't bring much in terms of performance. Shielded cones (scuttle or behind a vented headlight) are better but will still be noisy.

An ARC Magic chamber with a factory air box will be as close as you'll get to complimenting the exhaust in terms of flow (this is what I have) but a JR or ARC intake would be one step up (if you can find a good one).

Good luck deciding

[Mazda Mender]

All mine are running aftermarket filters, they are cheap enough for a good one, not the cheap crap off the bay of E, but any gains will only happen when you fit the rest in line, IE:- down pipe, cat , mid seciton and box.
Is your MK 1 de-catted ? as that will make a big difference to the noise, plus the Mx5 parts/IL motorsport box can be load, you could change the back box for something better and a better Grrrrrr out put, that way you can re-fit the cone filter.
M-m

[GlennyGills]

The car is too young to be de-catted (1996). I really don't want to change the new S/S back box as it was not cheap, so I am going for an aftermarket better quality foam jobbie. Perhaps it was just a perception that it felt faster with the Cone filter on.