Exchange unit
Baffled Rocker Cover
Our modified MX-5 rocker cover for boosted cars running a catch can, and for naturally aspirated engines built to see a lot of abuse. Any MX-5 cover, on exchange.
Finish
Colour
After something else? Ask about a special colour or a modification.
£350
Exchange, painted. Includes VAT.
Shipping £14.95 in the UK. Anywhere else, email us and we will quote the carriage. Delivery.
Exchange. Post your original cover back to us within 28 days of the new one arriving. If it does not come back we invoice a further £35.00. Sale terms.
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What it is
Breathing, Sorted At The Cover
On a standard MX-5 the crankcase breathes through a PCV valve on the intake side and a small breather takeoff. Add boost and that PCV sees pressure instead of vacuum, the volume of blow-by climbs, and the stock ports are too small for it. The usual result is a catch can that fills with engine oil far faster than it should.
Rather than hang more plumbing off ports that were never sized for the job, we modify the cover itself. The factory routes are closed off, two large ports go in on the exhaust side, the internal baffles are opened up so the whole cover can breathe toward them, and stainless wool in the chambers drops the oil out of the air before it ever leaves the engine.
It matters on a hard-used naturally aspirated engine too. A standard system breathes oil vapour back into the intake, and oil in the charge lowers its knock resistance. The full how and why is in the Field Note.
In the box
What You Get
- A finished MX-5 rocker cover, blasted, modified and painted
- The factory PCV and breather blanked, welded closed inside and out
- Two AN10 male bungs welded on at 45 degrees, ready for your hose ends
- The centre and exhaust baffles drilled through and packed with stainless wool
- The baffle plates sealed back on, welds dressed back before paint
A few colours to pick from. Tell us which when you order.
Hose ends, braided line and the catch can itself are not included. If you want the whole breather system supplied and fitted, say so and we will price it.
How it works
The Exchange
01
Tell us your cover
Which MX-5 you are running and which engine. The covers changed through the car’s life, so we build to the one you have. If you are not sure, send a photo.
02
We send yours out
A finished cover, built and painted, goes out to you. Pick your colour when you order. There is nothing to wait on while your own cover is off the car.
03
Your old one comes back
Send us the cover you took off. It goes through the same process and becomes the next one. That is what keeps the exchange price where it is.
Fitment
Any MX-5 cover. The price is the same across the range. The internal detail differs from cover to cover because the covers themselves changed, but the principle and the result are the same on all of them. Tell us the car and the engine when you order.
Finish
Painted as standard. Four to pick from: wrinkle black, wrinkle red, wrinkle blue and gloss white. If you would rather do your own paint, an unpainted cover is £280 and comes to you with all the work done and the welds dressed back.
Something else
Special Requests
The four colours above are what we keep. If you want a different colour, or the cam gears cut and exposed, or anything else doing to the cover while it is apart, tell us here and we will price it and come back to you.
Tell us which MX-5 and which engine you are running as well. If you are not sure, send a photo of the cover that is on the car.
£350 exchange, painted
Order One
Tell us which cover you are running and which colour you want. If you are not sure what your setup needs, ask.
Or talk to us about the whole breather setup.