Now that all of Mazdatrix's UHMW section is gone, does anyone know of another place that sells non-metallic solid mounts? I would guess that an all delrin moto, tranny "y", tranny crossmember and rear diff mounts would be a good way to go.

 

www.mmr-direct.com

That's where I am getting to order from, dirt cheap prices IMO!

 

I'm running MMR engine and tranny mounts, no complaints here!

Also, the threaded body makes the install easy as pie. I slide the puck portion under the mount, thread the rod through, lower the engine and i'm done. It's cake.

EDIT: no diff mounts yet, I have them but haven't installed them yet. One thing I noted with these on the engine and tranny is shifts are much more precise because you're not aiming for a gear thats out of place due to engine movement. Previous to this setup I was running solid engine mounts and stock tranny mounts and a fast 1-2 shift would either put me in la la land, or in 4th gear when really launching hard at the track. Now I can peg them like butter.

 

what is the differnce between UHMW Polyethylene and delrin? Ive seen the price differnce on UHMW Polyethylene vs delrin and Polyethylene is way cheaper.

 

looks to be the same as the mazdatrix ones.

When I called Mazdatrix, they said that their company flaked out and stopped responding to them, which is why they don't carry them anymore.

 

good thing I got mine when I did then.


On a side note concerning (near) solid mounts. be sure you have driven in a rotray car that has them before you get them. Reason I recommend this is I thought I was hardcore about engine vibrations/rattles vs drivenline stability. Turns out I am not nearly as hardcore as I thought. While I have grown mostly used to the poly engien and tranny mounts as they have broken in, these are still the first mod I have EVER done to a car that has made me want to drive it less.

Like I said, I have gotten used to it, but the first 1k miles were rough on my nerves, and I was frankly embarrassed to let anyone ride in the car because it sounded like it was going to rattle itself to pieces. Now that they have broken in the rattling has reduced signifcantly, but still its a concern to note to future purchasers. I have gotten to the point where I almost like them. At cruise the increased vibration is minor, but at anything over 5k its a cacaphony of rattles and engine noise transmitted through the frame.


BC

 

I really dont notice any negative side effect from my Banzai poly mounts. My stock passenger side mount was shot so I had a lot of drive train slack before. With the tranny in 5th on the highway, if I lift, the shifter doesnt budge. Before, when Id lift, the motor was moving so much that it would move a good 1/2 inch!

 

I saw my buddies polyurethane mount, and the hole was totally dissfigured from engine vibration. The metal sleeve was not disfigured, but the polyurethane mount looked like it had a slotted hole. this is after a year. It doesnt take the same type of abuse as our mounts. But , I can see the freeplay over time .

It didnt looke like these bushings came with a metal sleeve to protect the polyurethane bushing. That little bit of ffreeplay over time, rather get a stock bushing ,or find a company that makes another bushing

 

Arent the MMR bushings designed to go back on the metal part of the stock mounts? I know my banzai mounts came with new metal pieces so it woudnt just be the battle of Polyurethane v. Subframe and Motor mounts.

I pulled my motor after 6months of having the mouts in and they looked as good as new.

 

Go to your local aluminium supplier and have them cut you two pucks out of some 6065 3" aluminum rod. Then drill a hole through it. You'll need to measure the FC mounts but I think they need to be about 2.5" high. Will cost under $20.

 

I personally have been VERY pleased with the stiffened competition motor mounts from Mazdatrix (or mazda motor sports if you are a member). There is virtually no drivetrain slack, but it doesn't transmit a huge amount of vibrations like solid mounts.
Just something to think about.

 

Delrin (Polyoxymethylene) and UHMW (Ultra high molecular weight polyethylene)are both thermoplastics with very similar properties... Lightweight, very low friction, abrasion resistant, and good impact properties. They both are excellent materials but it appears that UHMW has better impact strength.

Source: wikipedia.org

 

Forgive me if someone said this and i missed it (i did read) but energy suspension make polyurathane bushings for rx7, i actually have an extra set that my friends gonna buy, if anyone is interested if he doesnt get them pm me.

 

They don't make the driveline bushings/mounts though. I agree that the Mazda Comp mounts are a good way to go. A threaded rod through a puck isn't the best way to do it, as the compression loads are all on the puck, and the tension loads are all on the stud (more or less) and this can and apparently has lead to breaking of the stud.

AWR mounts look really nice, but are expensive, although sometimes they come up for sale used for a good deal.

If you want plastic mounts, buy a stick of plastic from a plastic supplier and make them yourself, just like Aaron suggested with the Aluminum. There's multiple places online and there's probably an industrial type supplier in your area.

 

Oh thanks. The polyethylene is a lot cheaper than the delrin. Maybe I will make my mounts out of that. Thanks

 

Be aware that different plastics have different tolerances for heat, which could be a concern on the exhaust side mount, especially if there's no heat shield or anything. Over time they could heat up and deform, leaving the engine loose and leading to the rod snapping.