Solid mounts converted to semi solid??

[stubble88]

Am I crazy or can one buy poly bushings that would drop inside these solid mounts converting them to semi solid? Just looks very possible. Would need longer bolts.

[Bill Verburg]

Originally Posted by stubble88

Am I crazy or can one buy poly bushings that would drop inside these solid mounts converting them to semi solid? Just looks very possible. Would need longer bolts.

yes, you could do that

here's what my semi-solids look like

[PeteKz]

My answer: Yes. I stick to the rubber mounts on the engine and transmission. Solid or "semi solid" increase noise transmission to the chassis. The deflection over the length of the engine/transmission assembly is so small that I don't see how it changes the handling of the car. It just makes it noisier.

Unless it's strictly a race car.

[Bill Verburg]

Originally Posted by PeteKz

My answer: Yes. I stick to the rubber mounts on the engine and transmission. Solid or "semi solid" increase noise transmission to the chassis. The deflection over the length of the engine/transmission assembly is so small that I don't see how it changes the handling of the car. It just makes it noisier.

Unless it's strictly a race car.

Not true at all

[stubble88]

I guess what I’m asking is if they make a drop in rubber or poly bushing for these? I guess by the time I’m done buying that I could just buy some semi solids.

[PeteKz]

Originally Posted by Bill Verburg

Not true at all

The noise or the handling?

[Bill Verburg]

Originally Posted by PeteKz

The noise or the handling?

both
i just changed mine again, I have the adjustable Rennlines

the only noticeable difference is in shifting
solid is best
sss next, predictably stiffest insert is best and softest is worst
stock worst


no noticeable difference in NVH at all but the 3.6 w/ RS cams rocks the chassis w/ any of them

similar results in my 993, except the shifting is always way better

[stownsen914]

In order to make a semi solid mount, the bolt from the engine crossbar shouldn’t directly touch the metal portion of the mount. Otherwise the vibration will still transmit. Semi solid mounts like Wevo and Rebel sell isolate the bolt in the poly portion of the mount.

You might be able to convert the solid mounts if you open the bolt holes in the center of the mount so the bolts don’t touch, and have a rubber or poly insert to hold the bolt. You’d need a way to hold the poly insert captive in the mount, which sees quite a bit of force and vibration.

Simply dropping rubber or some other material into a fully solid mount with no other mods may not stop the vibration from transmitting

[stubble88]

Originally Posted by stownsen914

In order to make a semi solid mount, the bolt from the engine crossbar shouldn’t directly touch the metal portion of the mount. Otherwise the vibration will still transmit. Semi solid mounts like Wevo and Rebel sell isolate the bolt in the poly portion of the mount.

You might be able to convert the solid mounts if you open the bolt holes in the center of the mount so the bolts don’t touch, and have a rubber or poly insert to hold the bolt. You’d need a way to hold the poly insert captive in the mount, which sees quite a bit of force and vibration.

Simply dropping rubber or some other material into a fully solid mount with no other mods may not stop the vibration from transmitting

Ok. Thanks for this info. Seems easy enough to play around with. Thinking of just keeping them solid for now.

[A930Rocket]

So, I’m trying to keep my new to me 86 911 all stock, but what semi solid engine and trans bushings are the best? I’m interested in the better shifting.

Are there any of that look stock?

[SBell]

I would not just drop the poly in place. You'll likely see the bolt loosen itself rather quickly. Factory rubber and semisolid mounts have a steel spacer in the center of the rubber so that the bolts can be tightened to spec against something rigid. If you were to tighten them against something soft like rubber or plastic you likely wouldn't get them tightened all the way and because they're tightened against a soft material they will likely back out easily.

Sent from my SM-S931U using Tapatalk

[stownsen914]

Originally Posted by A930Rocket

So, I’m trying to keep my new to me 86 911 all stock, but what semi solid engine and trans bushings are the best? I’m interested in the better shifting.

I have the Rebel Racing semi solid blue (the stiffer ones) mounts in my racecar. Granted it's a racecar, but I didn't notice much if any increase in the vibration, but they are noticeably stiffer than stock rubber mounts in terms of engine movement.

I've also driven racecars with solid mounts, and I found the vibration pretty evident.

[PeteKz]

Originally Posted by Bill Verburg

both
i just changed mine again, I have the adjustable Rennlines

the only noticeable difference is in shifting
solid is best
sss next, predictably stiffest insert is best and softest is worst
stock worst


no noticeable difference in NVH at all but the 3.6 w/ RS cams rocks the chassis w/ any of them

similar results in my 993, except the shifting is always way better

Since I still have the factory shifter, I probably wouldn't be able to tell the difference.