Like the title says will a 13b intake fit a 12a?

 

will it fit? NO

can you make it fit? yes

 

A 13B's housings are 10mm longer each, so the six-bolt pattern on the 12a more or less stretches when applied to the 13B. The two intermediate plate studs stay fixed, the housing studs move 5mm each way, and the endplate studs each move 10mm from the center. This is why a manifold won't be a direct replacement. There are adapters out there that are functionally similar to wheel adapters, but you can usually find the right manifold you need.

 

This say's come's with adapter plate is that for the 12a? It's cheap only reason I consider.
http://cgi.ebay.com/ebaymotors/Mazda...spagenameZWDVW

 

looks like it...not a ton of transactions though...

 

Looks good to me!

 

That intake looks like a 12A with the 13B adapter plate. Go for it.