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First off, let me say that I installed a GMM rip shifter (street version, which meant I didn't have to yank the knob off the shifter, just undo the bolts holding the stick to the shifter, 'cause you use the same stick) this past week end. The installation went as good as expected. The shifter has definitely lived up to the hype. It is smooth and precise. I have noticed no additional road noise and feel less vibration at any given rpm. (I was going to put RP in at the same time but decided to wait a week so I could see the difference in just the shifter...)

These forums made me think I missed something because the installation went so well and shifter is so good. I went back under the car yesterday and checked everything and found everything tight, clean and dry. The precision and tightness of the GMM shifter is wonderful.

Anyway, my cofusion is about the B&M shifter. All the complaining about the B&M sparked my curiosity due to the installation and design of the GMM is so simple, so I went to the B&M website and looked at the shifter they offer and it looks very similar.


However, they call it the "New Precision Manual Sport Shifter for the 2005 Pontiac GTO" So is this a new design? Different than the one everyone has had problems with or is there something I am missing?

the only place I see that would possibly leak would be the seal between two machined surfaces that has an 'O' ring squished in between, and it's not like the seal is subject to high pressure (or any pressure at all is it?)

@groucho- Oh yeah, don't our GTO's come with a Momo knob? look here--> http://www.jhp.com.au/gkpbh.php

Cow

P.S. According to tremec, our transmissions have internal stops so they don't really need the stop bolts on the shifter 'tho I set mine to the recommended clearances...
 

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Galen's excellent critique tells the story, but I'll 'splain it :



The B&M's four bolts, bunched as they are along the back edge of the adaper plate, concentrate all of the mechanical force attaching the shifter in one small, off centered, area-- well behind the shift hinge point.

Hard 1-2 and 3-4 shifting imparts a force vector that is way the hell out of the shear plane, as it attempts to peel the front of the adapter plate away from the tranny housing. The force is at least 10-15 degrees off plane, in tension, headed down and back. Unlike the bolted-direct-to the housing GMM, the B&M re-used the OEM tansmission adapter plate which in turn bolts to the tranny housing. The tranny adapter plate, sitting as it does on the B&M-supplied higher-durometer-than-stock gasket, is still free to flex and move under this force.

Facts is facts: for a measly $100 more you can have a shifter that is better built and better designed, mounting in such a manner that eliminates the tranny adapter plate altogether, getting rid of one inevitable leak point.

Mounting issues aside, the GMM has an internal gate and detents that makes shifting far less sloppy and way more positive than the B&M does.
 

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Groucho said:
Galen's excellent critique tells the story, but I'll 'splain it :



The B&M's four bolts, bunched as they are along the back edge of the adaper plate, concentrate all of the mechanical force attaching the shifter in one small, off centered, area-- well behind the shift hinge point.

Hard 1-2 and 3-4 shifting imparts a force vector that is way the hell out of the shear plane, as it attempts to peel the front of the adapter plate away from the tranny housing. The force is at least 10-15 degrees off plane, in tension, headed down and back. Unlike the bolted-direct-to the housing GMM, the B&M re-used the OEM tansmission adapter plate which in turn bolts to the tranny housing. The tranny adapter plate, sitting as it does on the B&M-supplied higher-durometer-than-stock gasket, is still free to flex and move under this force.

Facts is facts: for a measly $100 more you can have a shifter that is better built and better designed, mounting in such a manner that eliminates the tranny adapter plate altogether, getting rid of one inevitable leak point.

Mounting issues aside, the GMM has an internal gate and detents that makes shifting far less sloppy and way more positive than the B&M does.


Thanks Groucho! (mine's not here yet :mad: )
 
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