AMS Motor Mount VS. OEM - Confused?&^%

rogue · Nov 2, 2009, 11:09 AM

So I installed the AMS mount today and found something very surprising...

1. Bolt that is used to hold the Motor mount the the engine is smaller by a large amount.

2. The hole on the OEM motor mount is much larger than the AMS one, but the whole on the AMS one is still to big for the OEM screw...

What puzzles me is why mitsubishi would use a bolt that is smaller than the inner diameter of the the Stock Motor Mount. And then Why did AMS use a smaller inner Diameter than that of the OEM motor mount.

Did some idiot on the factory assembly line screw with my car, or have others had this issue. I would think with the amount of slack that is left in the hole, it must not be doing a good job reducing engine flex.

See pictures here:

http://fusionrace.smugmug.com/Motors...-Motor-Mounts/

stokEd · Nov 2, 2009, 11:37 AM

No mistake, that's how they're designed. And it works.

I thought it was strange too when I first noticed. I figure it's to allow the bolt to trace the arc of the bushing center as the motor torques under load.

rogue · Nov 2, 2009, 11:44 AM

Quote:

Originally Posted by stokEd

No mistake, that's how they're designed. And it works.

I thought it was strange too when I first noticed. I figure it's to allow the bolt to trace the arc of the bushing center as the motor torques under load.

Blah.. I do not remember it being like that on the IX, but thanks for the response.

BigT · Nov 2, 2009, 01:31 PM

Hows the car running with the new mount?

rogue · Nov 2, 2009, 01:34 PM

Runs as expected.. More vibration during idle, I can tell the engine is not jumping back and forth.

LRM1981 · Nov 2, 2009, 02:00 PM

Did it improve the notchy shifting from 1st to 2nd and 2nd to 3rd?

rogue · Nov 2, 2009, 02:02 PM

I cant say because... I have a Works Short Shifter, AMS shifter bushings and AMS base Bushings. Also I have aonly driven the car once or twice since i put it on.. I will check.

goofygrin · Nov 2, 2009, 02:20 PM

Quote:

Originally Posted by LRM1981

Did it improve the notchy shifting from 1st to 2nd and 2nd to 3rd?

No, that's a function of the transmission.

OP, I've got the AMS bushing and I don't remember the issues you're describing. Are you sure you got the right one?

rogue · Nov 2, 2009, 02:23 PM

Well I hope I do.. I mean what puzzles me already is that the OEM motor mount hole is larger than the bolt going through it. The AMS one is smaller but still larger than the bolt.

Did you actually look at the bolt and the hole for the AMS one?

I would have hoped AMS would have chimed in by now...

Scott@AMS · Nov 2, 2009, 02:56 PM

Mitsubishi has done that forever. I am guessing they make the hole so large to account for possible minor differences between cars, kind of a manufacturing tolerance. In all reality though the hole size doesn't matter, when you tighten down the bolt the outer mount clamps onto the inner mount and that's really what holds the mounts together and prevents any excess movement.

Quote:

Originally Posted by rogue

Well I hope I do.. I mean what puzzles me already is that the OEM motor mount hole is larger than the bolt going through it. The AMS one is smaller but still larger than the bolt.

Did you actually look at the bolt and the hole for the AMS one?

I would have hoped AMS would have chimed in by now...

rogue · Nov 2, 2009, 02:58 PM

Quiet odd, considering it is mount.

flyguycfi · Nov 2, 2009, 03:07 PM

So does the car vibrate a whole lot now or just a little bit more? I'm really considering getting a few of their motor mounts, but really have no way to judge how much more it's going to vibrate.

Scott@AMS · Nov 2, 2009, 03:10 PM

We offer the front motor mount in 2 versions, a red race version and a black street version. If you are really worried about vibrations I would get the black version. It still is much stiffer than stock but very streetable.

Quote:

Originally Posted by flyguycfi

So does the car vibrate a whole lot now or just a little bit more? I'm really considering getting a few of their motor mounts, but really have no way to judge how much more it's going to vibrate.

chriswolf81 · Nov 2, 2009, 04:16 PM

Quote:

Originally Posted by rogue

I cant say because... I have a Works Short Shifter, AMS shifter bushings and AMS base Bushings. Also I have aonly driven the car once or twice since i put it on.. I will check.

I got all that no difference.

farmeryean · Nov 3, 2009, 10:53 PM

I have about 2k miles on the ams street (black) motor mount. At first I was suprised at how much this street mount vibrated, but quickly started liking it because now I can feel the car through the pedals and steering wheel more, knowing when to shift without looking at the tach when the music is loud. It does vibrate at idle but not that bad, definately worth the improved connection to the car. The shifting is much better, haven't missed a shift since I got it. I also swaped out the front shifter bushings about 5k miles ago, but there was an improvement with the notchiness with the ams motor mount. It's still notchy and grinds a tad when its cold but it is a much smoother shifting experience overall.