NB8A exhaust burble

wiztek · Postby **wiztek** » Mon Mar 26, 2012 9:52 pm

Hi
My NB8A has a slight exhaust burble - i can only hear it when i come off the accelerator and the engine revs down, there is a 'burbling'.
Note its only audible in 1st gear in confined spaces and moving at slow speeds.
Is this normal/what is it?

hks_kansei · Postby **hks_kansei** » Mon Mar 26, 2012 9:58 pm

Stock or modified exhaust?

I find mine does it as well when cold, I've got a free flowing (well.... bascially hollow milo tin) muffler.
Mine also makes a loud bang on fast gearchanges when it's hot.

I'm not 100% on what it actually is, one theory I've heard is that it;s the hot and cold airs mixing in the pipes and making almost mini thunder.
The other is the bits of unburned fuel in the system igniting and burning off as they go through the hot pipes.

As I said, not sure what it is (someone like Nitrodann probably does)

Mine's been happily popping and burbling for about 18 months without any ill effects.

wiztek · Postby **wiztek** » Mon Mar 26, 2012 10:01 pm

Stock exhaust..

Regie · Postby **Regie** » Mon Mar 26, 2012 10:19 pm

Sounds normal.

My nb did it with stock and a smb exhaust

My nc does it all the time

I love the sound

wiztek · Postby **wiztek** » Mon Mar 26, 2012 10:24 pm

Yeh i dont actually mind the sound, was just a bit concerned as this is my first MX5 (picked it up Sunday, and boy, everything they say is true).
Now to find a replacement radiator without paying OEM prices...

hks_kansei · Postby **hks_kansei** » Tue Mar 27, 2012 7:34 am

I remember a lot of people used to use a brand called Cooling Pro a while back, they were cheaper than the OEM and had metal tanks top and bottom rather than plastic.

I never looked too hard into them so don't know specific details, but if you search for cooling pro, or radiator, etc you should find a few of the old threads where people used them.