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Moroso air/oil separator kit (small body)

Moroso air/oil separator kit (small body)

Regular price $199.00 USD
Regular price Sale price $199.00 USD
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More expected on Jun 30, 2024.
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Your crankcase is full of oil mist. If that gets into your intake via the PCV system, you'll find yourself burning oil. Not only is it uncool to have blue smoke coming out of your tailpipe, oil is also very low octane so it can mean a loss in power. Mazda knows this, it's why they put an oil separator on the 2004-05 Mazdaspeed. Unfortunately, it's harder to make a good oil separator than you might think and there's a lot of misinformation out there on how to plumb them in correctly.

Moroso knows, though. Their separator - also known as a catch can - has a tight steel mesh to encourage the oil to drop out of suspension, and it collects in the lower half. The separator must be disassembled to be emptied, and has a nice knurled grip to make this easier. Includes all fittings to install on a Miata.

This kit uses a smaller canister than our other one to fit in smaller spaces - it measures approximately 4.5" high by 2" diameter. Fits all NA and NB Miatas, including those with ABS.




Ships free in the US.

There are no shipping restrictions on this item.

What does it fit?


Emissions do not apply.


45 days



Customer Reviews

Based on 4 reviews
Quality meat and potatoes, missing the sides.

Love the quality of the can and even the billet clamp, very pretty in the engine bay.

My kit was missing a mounting panhead bolt so I couldn't mount it to my engine bay out of the box, luckily I had some bolts lying around I used.

Also as others have pointed out it would have been nice to have some hose clamps out the box too.

Well made

Very easy to install. The finish on the oil separator is nicely done and all fittings supplied work well. The oil separator/catch can was pretty difficult to twist open for the first time but subsequent 'openings' were fine.

The tube routing is a bit on the "ugly" side but you can easily get creative with it - the liming factor is the angle at which the pcv valve exits the manifold as well as the location of both the pcv valve and intake plenum fitting. None of which are at fault of Flyin' Miata.

Excellent fit

I have the larger version but was perfect fit and fit and finish on it was excellent

Nash C.
AOS Review

Easy install, we ran a longer tube down to the bottom of the trans for the fitting instead of having the drain up high. I have yet to check to see if it is accumulating blowby (I am sure it is), but I will at the next oil change interval. Quality construction. Addition of hose clamps would have been a nice addition to this kit.