View Full Version : Closer look at NA6 VS NA8 HVAC Heater Core

03-20-2015, 04:33 PM
So much of the old threads I found are incomplete or never updated info so here is the final answer.

I chose AutoZone because of the lifetime warranty. A little expensive, $40 more but since this is a keeper I may as well spend $130 and get the peace of mind. Yes it is the HVAC for the NA6 90-93 Miata.

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2108_zpss3dhmrk3.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2108_zpss3dhmrk3.jpg.html)

Here is the difference but "DO NOT WORRY"......

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2100_zpszd491dvy.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2100_zpszd491dvy.jpg.html)http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2101_zpsekcol0im.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2101_zpsekcol0im.jpg.html)

Inside the housing box it fits like a glove....

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2102_zpsr6mxwxsn.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2102_zpsr6mxwxsn.jpg.html)

Look at the NA8 original......

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2103_zpsnrhsksg6.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2103_zpsnrhsksg6.jpg.html)

Once the housing is installed, the return tube is pretty much in place out in the engine bay........

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2105_zpsqid7mla6.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2105_zpsqid7mla6.jpg.html)

The difference with the NA8 OEM is not significant.......

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_2107_zpszh8funfr.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_2107_zpszh8funfr.jpg.html)

03-21-2015, 10:29 AM
Wahoooo!!! Glad you were able to get it all sorted and find a replacement for much, much cheaper then originally expecting...

03-21-2015, 11:46 AM
How hard is it to take out and reinstall?

03-21-2015, 12:57 PM
How hard is it to take out and reinstall?

The one pictured is easy coz' it is on my 95 project where the dash is out. But the one I just did on my 94 is quite a challenge. You have to take the driver seat out to give yourself some room. If the door was easy to take out this will also make this job easy but you will have to be on your knees for most part. If you're left handed it will also help as the position of the core is on the side of the housing. To get to the core you need to remove the lower dash metal cover, remove the plastic cover of the core which is held by a screw then the core it self is held by two metal screwed down clips. Once you remove the return tube (a separate tube held by a short hose and clamp) given that you have removed the two hoses in the engine bay firewall that connects the core to the entire route then you simply slide this out.