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Discussion Starter #1 (Edited)
Hi! This is my first post and ive done my best using forum search and googles. At this point im really in need of some experienced advice before i go ahead.

Background details:
I have a 2012 Mazda 3s 2.5L non ski active manual trans. Having recently purchased the vehicle my partner and i love it and use it sparingly as a daily driver/weekend car while our other car bares most of the driving.
The car is currently stock but we would like to make some modifications that aren't extreme or for lack of better words distasteful & rice-burneresque. Mods that will retain some of the quiter and [imo] classier side of the vehicle at idle and cruise but make some grunt when worked.
I find that the car is lacking a little on pick up and want to improve its sports side by opening it up and having read that a TMM also improves this.
Borla axle back exhaust is reputed to be the quitest performance option with a very nice note. Id definately like to pair a Borla with msds headers. People have mentioned that with a header you should sure up the engine with a better RMM or you could get some knocking issues. So that would go in at the same time as headers.
K&N CAI likely unless something different is be better suited. k&n comes with the isolation box so fits in with local laws.
At a later date i may fit a Racing Beat sway bar and springs kit as it seems to have been designed as an improvement over stock but nothing extreme from what i can gather. Mag wheels will be one of the last things to do.

But anyhow...shortly after purchasing ive noticed a knock from the front left of engine bay. After taking it to mazda they gave it a check and quick drive and reported the issue is with trans mount.
Their recommended fix is to insert a 'trans mount insulator' into the stock TMM. I really dont like this idea and would prefer, at this point, to upgrade the trans mount with something more reliable than the stock engine mount and insulator. Also a TMM that would compliment future mods.

Now is where it gets a bit hard for me to figure out what i should. The car is garaged for the most part until i get this fixed. I hate driving it with this noise and a bit concerned about doing further damage.

Choices for the 2012 m3s are pretty limited unless ive missed something :( From researching my option for a complete mount replacement is from TRZ which some people have found to be too harsh
Or the mount insert from CS which works with the stock TMM :/
**Are these really my only options??**
I would freaking LOVE to get a JBR TMM, it looks like a good quality piece - but it definately only fits mspeed3??

If i get a TRZ trans mount will i need to replace RMM at same time for engine harmony/NVH? Or will a RMM help cancel out vibrations from the TMM by balancing out the engine or something?

What are peoples recommendations for a RMM to pair with a TRZ TMM that will suit my end goals? Something good to sure up the engine but not so stiff that it could make the ride into something very unpleasant.

I understand though that any mount will of course cause an increase in NVH and will take time to wear in.

Thankyou heaps for any much needed help.

135 Posts
Don't know if you bought a rear motor mount for your 2012 Mazda 3S. A good option for little money would be knock off of the Ford 2014 Focus ST / Ford Electric Focus rear motor mount ...I bought mine off Ebay for my 2011 Mazda 3S and I'm quite happy with it. Mount is by Torque sells for under $33.00 shiped. You will also need the Ford horizontal mounting bolt.
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