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Old 10-11-2008, 08:03 AM   #1
SpooledupRacing
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Default Comp diff mount vs OEM diff mount

Ok I have begun to completely redue the entire suspension.. the last steps are to either put on a perfectly good OEM mount or put on a comp mount from mazdatrix..

I have redone ALL the bushings with solid mounts and urethane bushings my question is:

Is the comp diff mount that much better then the OEM mount or not?

This is on a turbo drivetrain and I am putting in an lsd plans for big power I just want to know for those who have used them is it worth the change? should I save the 100.00 and just use my current stock mount (I have 2 both look just fine)

any info would be great..

THX.






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Old 10-11-2008, 10:26 AM   #2
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The stock diff mount "should" be fine. It really comes down to the amount of torque you're going to be pushing through the system. The Competition or Solid Diff mount (I'm assuming you're talking about the front mount) will transfer more vibration to the subframe and to the body and cabin than the stock--but it also won't flex nearly as much when excess torque is applied through the differential. Something else to consider would be to install the Poly/Solid bushings in the rear mount of the differential. They will have a much larger impact on how much torque can be sustained in the system due to the moment arm.
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Old 10-11-2008, 10:42 AM   #3
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The comp mount isn't very noisy, and its pretty stout. If you're not drag racing then your OEM will work just fine.

The biggest thing is that the front of the diff snaps upwards on a hard launch or simply with alot of power going through the drivetrain. Best way to minimize that (because its that force that breaks the front mount) is a pinion snubber to prevent the diff from moving up too far so everything stays inline. They're simple to install - and cheap.
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Old 10-11-2008, 11:14 AM   #4
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Vex if u have read my build u would know that I have replaced ALL of the mounts/bushings

the rear deff leg mounts have MMR solid mounts, the rear subframe has MMR solid mounts, the dtss bushings were replaced with MMR solid mounts, the rear control arms have new upper oem bushings and new oem lower pivot bushings, the car is getting a new adjustable camber bar, has new front camber links and trailing arms

I wont get into the front end lol


my other choice was to just make a custom solid mount.
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Old 10-11-2008, 04:49 PM   #5
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dont use a solid mount on the front of the diff- it will tear the mount off of the subframe. use a pinion snubber. HELP part # 31052. its 7 bucks.
might as well use a competition mount along with it tho- it will help reduce the diffs nose movement. less movement = less wheel hop.
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Old 10-12-2008, 09:40 AM   #6
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thx for the part number I will get one..
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Old 10-20-2008, 06:52 PM   #7
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Just FYI, back when I had my TII I installed the comp mount after I broke the stock one. The next time something back there broke, it was the bracket on the subframe. So it's not just a solid mount that will break it. When I replaced the subframe I did the pinion snubber thing too.
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Old 10-20-2008, 07:36 PM   #8
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wow, that's intense.
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Old 10-20-2008, 08:24 PM   #9
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I hope that don't happen to me..
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Old 10-20-2008, 08:43 PM   #10
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thats what the snubber is for
with a snubber and a non-solid mount.. it wont break (unless you wheel hop like mad, then maybe)
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Old 10-21-2008, 07:24 PM   #11
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The purpose of the mounts are to absorb energy generated from the torque of the diff during launches. A solid mount would transfer all that energy into it's attached components, instead of absorbing them. As a result, other parts of the rear subframe will have to absorb energy that they were not supposed to see with the non-solid mount, causing more problems in the long run.

I'm convinced the pinion snubber is the way to go.
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Old 01-22-2010, 01:26 AM   #12
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i know this thread is old as god knows what but where is this snubber available? also i was looking at the racing beat mount that they have for $82.00, is that a good mount?
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Old 01-22-2010, 02:14 AM   #13
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snubber is available at baxters, oreilys, autozone i think, etc. its a HELP brand product, cant remember the part number.. its around somewhere. its 7 bucks.

for the front diff mount, go with mazda competition mount. also dont remmber where to get it lol. maybe the mazda dealer?
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Old 01-22-2010, 07:24 AM   #14
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well corksport sell the front diff mount as well as racing beat and mazdatrix. the part number for it is on this thread so we're good for that. but the corksport mount sells it as a kit with the other mounts for the rear subframe which makes it really expensive compared to buying it from RB with the same mounts and more!
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Old 01-24-2010, 05:28 PM   #15
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There is a thread at the other forum that explicitly discusses the options for pinion snubbers. http://www.rx7club.com/showthread.php?t=761710

Since the energy suspension box comes with two pieces, I can sell you the one I have left.
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