Well tonight I was bored and I just got done machining some motor mounts for a buddies C5 vette. He went with solid billet alum 6061 T6. So this got me thinking about the mounts I want to make for my car and possibly offer to people after I try them out. Of course it would be trial and error but thats how parts are made anyways right?

Only took me 5 minutes to draw up but I wanted to get the idea across with pictures and get peoples opinion and idea to make the better/modify them

Here is what I had in mine

The actual mount is going to be the same material, 6061 T6 alum. However I was thinking that was too stiff for me and I decided to bore out the center to 2" and insert 80A durometer (polyurethene). By doing this I am hoping to take away some of the vibrations and maintain the stiffness the aluminum would give.

The mount dimensions are 1.75" (H) x 3.0" diameter. The poly insert is 1.75" x 2.0"

Here are some VERY SIMPLE pictures..

Solid view

Transperant view

Dis-assemblied view for those that cant visualize like me

Is this something worth trying? I havent really seen people try this before so I figure that I will give it a shot. I am going to be making them in a couple of weeks so lets get some good info in here.

 

I think it would be ok but you'll need rubber on the top and bottom to take out and vibrations. It will also allow for a nice firm clamp buy compressing the rubber. I like the aluminum body as it will house the durometer from cracking/breaking/moving. Keep it up! When you want another test subject opinion just ship them over... You know my address!

 

Sure thing...

I start modifying the mount and see what I can come up with.

 

looks like a good design, but like what mono4lamar said, rubber on the top and bottom would be good to eliminate "metal on metal" contact and vibration.

when you're done i'll be waiting for a free sample :] 2 actually.

 

Something like this? Granted its not a rubber top but I feel like it would help out more with the vibrations. I think all I need to do is come up with a nice clamp for extra strengh to keep it all tight.

In this pic I took the single piece of poly out and used 2 poly inserts with lips on the end. Plus it would better since the engine and subframe are all metal to metal contact. The poly can act like a cushion.

 

Poly is hard, it will transmit vibrations. Also, poly is hard enough to "wear" or "shift" with engine torque. Rubber will not slide... especially after being compressed and it will surely dampen the vibrations.

 

the bolt is enough to transmit all the vibrations. if someone wants to do this right they will cast some polyurethane around 2 fasteners which do not touch.

 

I think you got the idea of the "hat" on the bushing, but in case you need something sloid to visualize, look at the Kartboy shifter mount bushings, http://www.kartboy.com/basket/catalo...y_class=KB-003
for the WRX. Just an idea, when I seen your drawing, they came to mind. They are two piece, so maybe that is something you could try as well. PM sent for a crazier idea.

 

No PM

 

nice work charlie !!! lmk when you get them made ... might be intrested in some

 

Can we say Knock readings.......

-J

 

Interesting, Use part painter to apply some materials to each part. Do you use Edge much ?

Shaun

 

congratulations on (nicely) designing a part for the FD that it doesn't need.

motor mounts are not the problem nor are they the solution. the motor should sit on mounts that absorb all the NVH.

there are two needs (NVH insulation & Torque absorption) that must be satisfied and mazda clearly compromised and attempted to solve both needs with one component, in so doing Mazda failed in both areas.

result: torn motor mounts & cracked PPFs.

the proper solution is to take ALL of the torque force from the motor mounts not to stiffen them to resist an entirely different force.

David Garfinkle's engine torque brace (ETB) is, pardon the pun, the missing link. add the ETB and you will have no mount problems. you will have no PPF problems.

consider our engine as a triangle. the bottom two corners being attached with motor mounts. all the engine weight sits on the mounts which sit on the frame.

instead of firming up the mounts to resist torque connect the top of the triangle to the inner fenderwell/chassis. you now have 17 inches of leverage to resist torque. you have the mounts supporting vertical engine weight and absorbing NVH.

win, win.

if you are into designing how about doing the two bushings that every modded FD needs... the upper differential bushings and the bushing at the front of the lower longitudinal rear links. sell them as a package.

i applaud your efforts, i appreciate your desire to add some NVH absorption, but stiffer mounts are not the correct way to solve the problem.

Garfinkle ETB... should be on every modded FD. (notice it has a touch of rubber in it). BTW, i paid full boat for mine and have no connection w David.




hc

 

Nice design, but I think it's not 100%. As others have said, for a motor mount to really work, it needs to be insulated from the motor for vibrations. That means breaking the mounting bolt so everything doesn't get transmitted through it. If you're going to use your design, with basically a solid case running full length, I'd suggest just make it easy and make it solid. I think it wouldn't be that far off your design for vibrations transmission.

 

Appreciate your input. I guess the alum housing on the mount would be a good way to house whatever material is inserted. Out of the 2 sets of poly mounts I used they both cracked and broke..Both on the passenger side. Either way I still think its an improvement.

By all means im not much of a designer, I was just messing around with solid edge last night cause I was bored. I was just shooting out the idea and maybe getting some feedback. I guess I recieved it

 

I'm not sure I follow....the design of the OEM motor mounts, specifically the driver's side mount, is indeed the problem. If it weren't, there would be no need for a solution. Garfinkle's ETB is one way to solve it. But there might be others without increasing NVH. At least I'll find out soon when I reinstall my motor with a set of Noltecs.