Question about BB 4speed crossmember

[Z28DZ]

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I forgot to ask. Does the same BB 4 speed crossmember fit all three years 1967-1969?

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To the best of my knowledge, yes.

Ed

[Ohio427]

Greg, great site you have there. The pictures tell me what I wanted to know. The picture of the SB crossmember is exactly like mine. It shows the bolt holes to the right of the opening. I just don't understand how mine bolted up with BB engine mounts and SB Xmember. Do you guys think that I should replace the SB with a BB xmember. I worry now that with this combination that I am putting undue stress on some part of the drivetrain whether it be the rear end, transmision or engine itself. It just seems like something has to be taking the force of the 1/2". I have put over 500 miles on this setup and haven't noticed anything unusual like an engine or drivetrain noise or vibration.

[YENKO DEUCE REGISTRY]

Your setup is fine, there are deuces with 100k+ miles on them with the mis-matched components - without problems! The universal joints make up for any alignment issues. I'm not sure I'd be throwing a set of slicks & caltracs on there, but for 'normal' usage it will be ok.

[Ohio427]

Marlin, Thank you. That's what I have been wanting to hear. I'd hate to go through changing anything when everything runs well as is. With my luck, the new & right crossmember would probably not line up while I had no problems with the wrong Xmember. I was just afraid of something developing in the future because of this. This site is truely a treasure of knowledge. Thanks to all.

[NCGuy68]

Good info here Gents on a much over-looked topic. Allow me to add a little more:

The OEM shifter mounting holes are different relative to the tranny mounting holes on big block xmembers. They are offset to the left about 1/4" compared to SB. This allows the BB shifter linkage to align correctly. Yes, a mismatch will work, but thats not the way they were from the factory.

This applys only to 67-8 Camaros.

[YENKO DEUCE REGISTRY]

Hmmmm... I thought the shifter rods made up that difference, but not completely sure

[NCGuy68]

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Hmmmm... I thought the shifter rods made up that difference, but not completely sure

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Many people think there is no differance. The BB linkage and the stablizer shaft are offset to align with the BB xmember. The assembly manuals show this and I've noted it on a number of unmolested BB cars thru the years.

[nuch_ss396]

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Good info here Gents on a much over-looked topic. Allow me to add a little more:

The OEM shifter mounting holes are different relative to the tranny mounting holes on big block xmembers. They are offset to the left about 1/4" compared to SB. This allows the BB shifter linkage to align correctly. Yes, a mismatch will work, but thats not the way they were from the factory.

This applys only to 67-8 Camaros.

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69 only has a similar issue. The shifter rods are about
1/3" longer to accomodate the mounting of the shifter with
that special ( again, BB only ) horseshoe mounting plate.

69 BB's have lots of these accociated issues. The lower
reverse lockout rod is also different for BB 4-speeds.
The flat nut for the Hurst shifter adjustment is a racetrack
shape vs. the rectangular shape of the SB's. Once you start
you just can't stop.

Steve

[YENKO DEUCE REGISTRY]

I hear ya! We actually don't know why GM installed the BB transmission crossmember with the LT1 application. We have confirmed that the engine mounts are indeed the SB version, and the crossmember is not the Pontiac version. I wish I could tell you why, but.... that's GM

We have speculated that the BB Xmember was retained under the COPO 9737 package because that package had been applicable to only BB cars for the prior two years, but we agree that it's a stretch and pure speculation.

The deuces actually have the BB shifter rods, but the SB shifter attaching bracket (no 1/2" offset), along with the '69 Camaro Z28 shifter mechanism with a Pontiac GTO bench seat arm. Confused yet?

[nuch_ss396]

[ QUOTE ]
Your setup is fine, there are deuces with 100k+ miles on them with the mis-matched components - without problems! The universal joints make up for any alignment issues. I'm not sure I'd be throwing a set of slicks & caltracs on there, but for 'normal' usage it will be ok.

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Marlin,

I'm a little confused here. The Deuces are LT-1 drive
trains and as such would use a SB X-member - right?

Also, if the SB works, why did GM use the special BB
4-speed X-member we are discussing here? As I mentioned
earlier, every BB 4-speed Camaro I ever saw ( correct )
used this special X-member. You're obviously knowledgeable
about this stuff and I hate to disagree with you, but I
just don't see the SB X-member being correct. I'd welcome
your comments otherwise. Always good to learn from others.

Steve