mortimersnerd
Member
I know this is likely old news, but thought I'd share anyway. I picked up a CP-E 60 durometer rear motor mount from JP @ Edge Autosport yesterday (www.edgeautosport.com) and got it installed last night. Here are the thoughts:
Install: Couldn't have been easier. If you can't do this, you shouldn't attempt an oil change. I did in under an hour with a bum shoulder. Three bolts to take off the trans side of the mount, one bolt where the mount connects to the unibody, and one bolt that connects the mount to the trans piece. Swap out the mount, reverse it the above and you're done. It took me longer to put the car on jackstands than it did to swap the parts (discovered my car doesn't clear my ramps...doh!)
The Drive: This may the the best bang for the buck mod out there. The engine feels much more connected to the car and there is a big change in power delivery. I'm not seeing a massive difference in how much power is laid down, but there is a significant difference in feel and the ability to modulate power delivery. I'd be curious to dyno before and after the installation of one of these, as I'm guessing the torque curve would be very slightly sharper. You have a much better sense of what the car is doing and it makes driving a more raw, pure experience. I feel more confident about flogging the car hard as it does a better job of communicating what is going on with the engine. The turbo feels like it hits a little harder and I'm assuming the old RMM was flexing as boost came on. Wheel hop on a hard launch is better and I suspect this will make driving in the rain a very different experience.
Shifting is much improved and I'm now pretty happy with how the car shifts. I can do both the 1-2 and 2-3 shift more agressively and have yet to muff a shift. Overall feel at the shifter is also improved and less mushy.
Vibes aren't bad, but they're there below 1200-1500 RPM, especially with the A/C on. I'm anticipating this will ease some as the mount breaks in, but I can see why Mazda doesn't put these mounts in stock. I'm glad I went with the 60 duro (its actually marked as 65, for whatever that is worth) instead of the 75 or a poly dogbone mount. It would be annoying if it was any worse since my car is a daily driver that isn't going to see much track or autocross action. There is also a small vibe that happens right about the 2000 RPM mark that is actually kind of cool. There is a very small increase in interior noise that is well worth the performance benefits. The difference in NVH is virtually nil above 2000 RPM
Overall, I'm really happy with the part. The car feels a little bit more like my old '73 Datsun SP autocross car. The only people who shouldn't get one of these are folks who should probably be driving Buicks. I'll update this if things change significantly as the mount breaks in. I also want to give a shout out to JP/Edge, as he really bent over backwards to accomodate what I was looking for. I'll be giving him more business in the future. Thanks for reading!
Install: Couldn't have been easier. If you can't do this, you shouldn't attempt an oil change. I did in under an hour with a bum shoulder. Three bolts to take off the trans side of the mount, one bolt where the mount connects to the unibody, and one bolt that connects the mount to the trans piece. Swap out the mount, reverse it the above and you're done. It took me longer to put the car on jackstands than it did to swap the parts (discovered my car doesn't clear my ramps...doh!)
The Drive: This may the the best bang for the buck mod out there. The engine feels much more connected to the car and there is a big change in power delivery. I'm not seeing a massive difference in how much power is laid down, but there is a significant difference in feel and the ability to modulate power delivery. I'd be curious to dyno before and after the installation of one of these, as I'm guessing the torque curve would be very slightly sharper. You have a much better sense of what the car is doing and it makes driving a more raw, pure experience. I feel more confident about flogging the car hard as it does a better job of communicating what is going on with the engine. The turbo feels like it hits a little harder and I'm assuming the old RMM was flexing as boost came on. Wheel hop on a hard launch is better and I suspect this will make driving in the rain a very different experience.
Shifting is much improved and I'm now pretty happy with how the car shifts. I can do both the 1-2 and 2-3 shift more agressively and have yet to muff a shift. Overall feel at the shifter is also improved and less mushy.
Vibes aren't bad, but they're there below 1200-1500 RPM, especially with the A/C on. I'm anticipating this will ease some as the mount breaks in, but I can see why Mazda doesn't put these mounts in stock. I'm glad I went with the 60 duro (its actually marked as 65, for whatever that is worth) instead of the 75 or a poly dogbone mount. It would be annoying if it was any worse since my car is a daily driver that isn't going to see much track or autocross action. There is also a small vibe that happens right about the 2000 RPM mark that is actually kind of cool. There is a very small increase in interior noise that is well worth the performance benefits. The difference in NVH is virtually nil above 2000 RPM
Overall, I'm really happy with the part. The car feels a little bit more like my old '73 Datsun SP autocross car. The only people who shouldn't get one of these are folks who should probably be driving Buicks. I'll update this if things change significantly as the mount breaks in. I also want to give a shout out to JP/Edge, as he really bent over backwards to accomodate what I was looking for. I'll be giving him more business in the future. Thanks for reading!
