well after looking at the motor mounts and knowing the abuse i will be putting them through i have decided to build a set of solid motor mounts. i have done this on another of my cars and it was a night and day difference. the Z should still idle very smooth so i am expecting hardly any vibration at idle, if i do, who cares it is cool to have the motor shake the car! looks to be pretty simple to do and will almost eliminate drivetrain losses and movement. it should have tremendous predictability on up and down shifting as well as throttle control compared to stock. will be posting pics of it in my other thread '2nd day into built motor'
has anyone else tried this? results?

 

I did on my RX7 and it made a noticible difference on the track.

 

i'm very interested in this idea... other than NVH, what is the downside to doing this?

ahm

 

I'd try poly bushings before solid mounts...but if you say you've done it before, you must have a pretty good idea on how it will feel.

For a daily driver/weekend racer, I'd definitely go the poly mounts route. My buddy's turbo civic hatchback feels like it will break my teeth at idle, but then he doesn't drive it daily, he only races it.

 

I talked to several of the larger companys about poly bushings and no-one said they would make them for the Z.

 

Because the mounts are weird, No way to build an insert for them really. Just make solid mounts out of steel and you could always swap them out. I was actually thinking about building some and making a jig. If anyone is really interested let me know, I'll start producing some perhaps. I wouldn't be hard, as I already have my motor out!

 

well finally got the motor together!! obviously not without my fair share of troubles. luckily i have the shop manuals so the actual assembly was not that hard, just alot of rechecking to make sure nothing gets missed.

 

here is a pic of what i meant to post, hahaha. simple yet strong. 1 3/4" dom cut at 3.25" with a slice off a 2" bar stock at 1/8" thick to make the ends. one 1/8" rubber isolator at each end to seat correctly. then 2- 1/2"x 6" grade 8 bolts and grade 8 nylock nuts. weld the ends on and drill the 1/2" hole through them, bam! you got a set of solid motor mounts. cost= about $20

 

AHHHHH. Inovation at work.. Like to see this kinda thing going on.. Just remember that a lot more of the "shock" will be absorbed through the tranny and drivetrain than before. Does the 350 use solid hub with dual mass flywheel or normal sprung hub with solid flywheel??

 

believe it is what you would call dual mass. i am also running the tilton semi street clutch set up so it will have a very positive feel for sure. i just heard some guys having problems with excessive chatter coming from the tilton and needing to get the engine dampers to help it out. this should help that out. even if it doesn't, i still like the feel of solid motor mounts and the predicability.