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Hi,

I'm about to swap the engine from a 2004 SE into my NB8B. The SE mounts that came with the engine are buggered. I'm tossing up between getting the OEM SE engine mounts or a set of Racing Beat SE engine mounts, which "the rubber in (the) mount is approximately 40% stiffer" according to their website.

I have plans for the car to make ~230hp at the wheels. I've been told that the OEM mounts were not designed to withstand that much power, but I've also read that stiffer mounts will make the car vibrate more. This is primarily a street car. I will be taking it to the track twice a year.

I'm unsure which mounts I should choose. I'm very open to suggestions. Any help or advice you can give me is appreciated

Decide which would annoy you more.
1) Slightly more noise/vibration (Doubt 40% stiffer would be that much noisier. Its not like they are solid mounts)
or
2) Replacing the mounts again when they fail prematurely cos they aren't designed to handle the extra torque the motor will have.

Personally I'd just put the stronger mounts in and cop any extra NVH with the knowledge they will last longer...

Also if you are shooting for 230hp atw then its likely you'll have a freer flowing exhaust which would increase NVH way more than the engine mounts would.

Or else just get Mazdaspeed mounts from Track Dog or FlyinMiata or Good-Win or MiataRoadster, etc. They're made by Mazda. They're stiffer and stronger but don't give any appreciable increase in NVH. They effectively supercede standard mounts for all NAs/NBs. Mazda know they screwed up with the original mounts: too soft, too weak.

oops: realised that the ones that RacingBeat are selling are just Mazdaspeed mounts anyway. Yes, buy them.

Thanks for all the advice!

I decided to go with the RacingBeat mounts, which are effectively Mazdaspeed mounts. Can't wait for them to arrive

Just for the sake of an added option, I think these 949 Hybrids look interesting. A Mazdaspeed rubber mount on one side, and polyurethane mount on the other.

This hybrid mount kit is not intended for frequent competition or track use. It is designed for the high HP daily dríven street Miata. It blends most of the engine locating control of our SuperMiata race mounts on the right side with a flexible rubber Mazda Competition mount on the left side. This combination allows only a tiny bit more vibration than two Mazda Comp rubber mounts but with about 80% less engine movement. This help keep your large diameter turbo exhaust system from banging around and cracking and rducs shifter movement.

http://949racing.com/Supermiata-hybrid-motor-mount.aspx

IL Motorsport often have good hardened rubber mounts, often at very decent prices. The Mazdaspeed / RB ones sound like the right decision for you though (y)

joshuam wrote:IL Motorsport often have good hardened rubber mounts, often at very decent prices. The Mazdaspeed / RB ones sound like the right decision for you though (y)

Not for you,but for other forumites,really happy with my IL MotorSport mounts and no issues with vibration.

Peter.

Delrin race ones in mine were the biggest single factor in reducing the civilizedness of it. Not that I care any more.