Not that you’d need to know, but incase you’d like to for extra scene points or whatevs… But there are some fairly obvious difference between NA and NB cam covers.
Which is which?
Fresh back from Chemical Strip, three of these covers fit the NB/ MK2 mx5 models. But how can you tell?
Firstly, the NA/ MK1 covers are simple to identify by the lack of crankshaft positionsensor or CPS, found on the front, only on the NB onwards. Mounted on the nose of the crankshaft, it was introduced for the detection of misfire in the ODBII engines.
Telling the NA 1600 and 1800 covers apart from eachother is most noticable by the lettering… The NA6 has recessed letters whereas the NA8 has raised letters. (This is only The case with N.A. engines…. NB engines are ALL recessed.) The NA8 is also slightly longer.
The NB models however, arent that simple. On both the 1600 and the 1800 MK2 covers, the lettering is recessed. If you put them side by side, there are some notable differences to tell them apart…
NB6 vs NB8
Firstly the most obvious difference here is the length. Just like the MK1 models, the 1600 is shorter than the 1800. You’ll also notice the difference in the positioning of some holes…
But the most obvious way to tell them apart – especially if you dont just cssually happen to have one to compare with – is the cut out on the back of the cover for the CAS. The NB6 is on the Inlet side on the left, and the NB8 is on the right for exhaust.
They will both have the sensor in the front in the same place.
So. Going back to the original pic… In order from left to right are….