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Moroso air/oil separator kit (small body)

The separator
Moroso air/oil separator kit (small body)
Cut down on oil consumption during hard use.

Availability: In stock



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.

Additional Information

Additional Information

Part number M04-37955
Fits: 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004 (non-MSM), 2005 (non-MSM), MSM
Manufacturer Moroso
Flyin' Miata exclusive No
Fits Exocet? Yes
Proposition 65 Warning: Cancer and reproductive harm
California emissions Emissions regulations do not apply

Customer Reviews 2 item(s)

Excellent fit
I have the larger version but was perfect fit and fit and finish on it was excellent
Review by Chris / (Posted on 9/28/2019)
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.
Review by Nash Carr / (Posted on 9/15/2019)
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