RCZ's 370Z Journal.

Z1Performance · 03-08-2010, 08:24 AM

Thanks Raul for taking the time out to try this out. I pm'd you but I'll post it here too since everyone should hear/see it. When I did the 75A (stiffer than yours) mount in my own car (350Z), I literally thought we had forgotten to reconnect my exhaust! I've got a build motor, Crawford headers, test pipes and a titanium exhaust. Everything inside the car resonated and was much louder. The rear glass had a noticeable resonance at the 2500-4000 rpm point. You even felt it in the steering wheel. This was done on a Saturday afternoon. I spoke to the engineer on it and he assured me to just keep driving it and it would settle in, so I did. It made a world of difference. By the following Wednesday, I had done around 350 miles in the car, a mix of highway and alot of backroad (so lots of shifting, accel/decel) and it had settled in perfectly. It was still a deeper sound in the cabin but none of the resonance was there.

If you've got some time to do some more miles, give it a go and let me know. I'll also talk internally and see what we can do about a lower durometer as well.

Thanks again!

puckshaw · 03-08-2010, 08:41 AM

Quote:

Originally Posted by Z1Performance

Thanks Raul for taking the time out to try this out. I pm'd you but I'll post it here too since everyone should hear/see it. When I did the 75A (stiffer than yours) mount in my own car (350Z), I literally thought we had forgotten to reconnect my exhaust! I've got a build motor, Crawford headers, test pipes and a titanium exhaust. Everything inside the car resonated and was much louder. The rear glass had a noticeable resonance at the 2500-4000 rpm point. You even felt it in the steering wheel. This was done on a Saturday afternoon. I spoke to the engineer on it and he assured me to just keep driving it and it would settle in, so I did. It made a world of difference. By the following Wednesday, I had done around 350 miles in the car, a mix of highway and alot of backroad (so lots of shifting, accel/decel) and it had settled in perfectly. It was still a deeper sound in the cabin but none of the resonance was there.

If you've got some time to do some more miles, give it a go and let me know. I'll also talk internally and see what we can do about a lower durometer as well.

Thanks again!

Interesting. So let's assume RCZ racks up a few hundred miles quickly and confirms this. How long before these go into production and are available for purchase?

m4a1mustang · 03-08-2010, 08:42 AM

Quote:

Originally Posted by Z1Performance

If you've got some time to do some more miles, give it a go and let me know. I'll also talk internally and see what we can do about a lower durometer as well.

Thanks again!

I'm hoping that things settle in as I'd love to firm up the shifting action.

theDreamer · 03-08-2010, 08:55 AM

Quote:

Originally Posted by m4a1mustang

I'm hoping that things settle in as I'd love to firm up the shifting action.

Hopefully it will, and I am sure RCZ will report back after a week of driving.
Thanks for doing this RCZ, hopefully now with one on a car we can dial everything in to get perfection for this part.

rednek01 · 03-08-2010, 09:11 AM

I mentioned this a while back when this was first talked about. I think you will find a lot of your problems are from using two different bushing materials. your motor mounts (most likely softer bushing) are fighting your trans mount bushing which is now much firmer.

You have to look as the motor and trans as one piece since they are solidly bolted together. And since this is the case you cannot use two different bushing materials because they will fight each other, which might be why the Z1 mount is 'loosening up" when in fact it is wearing out prematurely from fighting the vibrations that the motor mounts are allowing.

I learned all this the hard way with suspension bushings and it took me 3-4 bushing sets to realize you have to change out all the bushings that are affected to the same material other wise they are just going to fight each other.

So I feel that until you get some motor mount bushings that are of the same stiffness you will continue to have this problem.

03-08-2010, 09:11 AM	#5 (permalink)
rednek01 Enthusiast Member Join Date: Feb 2009 Location: Houston Posts: 352 Drives: Mustang GT Rep Power: 239	I mentioned this a while back when this was first talked about. I think you will find a lot of your problems are from using two different bushing materials. your motor mounts (most likely softer bushing) are fighting your trans mount bushing which is now much firmer. You have to look as the motor and trans as one piece since they are solidly bolted together. And since this is the case you cannot use two different bushing materials because they will fight each other, which might be why the Z1 mount is 'loosening up" when in fact it is wearing out prematurely from fighting the vibrations that the motor mounts are allowing. I learned all this the hard way with suspension bushings and it took me 3-4 bushing sets to realize you have to change out all the bushings that are affected to the same material other wise they are just going to fight each other. So I feel that until you get some motor mount bushings that are of the same stiffness you will continue to have this problem. __________________ Project オレンジ 2009 (FUGLY) Grabber Orange Mustang GT // SLP loudmouth axle back // JLT intake // BamaChips Tunes // ... TheDreamer's personal mechanic

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Edmonton Journal Review of the 370Z	BanningZ	Nissan 370Z General Discussions	13	08-09-2009 05:44 PM

03-08-2010, 08:24 AM	#1 (permalink)
Z1Performance Base Member Join Date: Aug 2009 Location: St. James, NY Posts: 237 Drives: 350Z Rep Power: 17	Thanks Raul for taking the time out to try this out. I pm'd you but I'll post it here too since everyone should hear/see it. When I did the 75A (stiffer than yours) mount in my own car (350Z), I literally thought we had forgotten to reconnect my exhaust! I've got a build motor, Crawford headers, test pipes and a titanium exhaust. Everything inside the car resonated and was much louder. The rear glass had a noticeable resonance at the 2500-4000 rpm point. You even felt it in the steering wheel. This was done on a Saturday afternoon. I spoke to the engineer on it and he assured me to just keep driving it and it would settle in, so I did. It made a world of difference. By the following Wednesday, I had done around 350 miles in the car, a mix of highway and alot of backroad (so lots of shifting, accel/decel) and it had settled in perfectly. It was still a deeper sound in the cabin but none of the resonance was there. If you've got some time to do some more miles, give it a go and let me know. I'll also talk internally and see what we can do about a lower durometer as well. Thanks again!