Help? Trans Crossmember ID?

[bugdewde]

OK.... I'm swapping out an automatic for a T-50 five speed in the '72 Kammback.... driver, not project.
Can anyone ID this Vega crossmember as a 5-speed? It seems set back further and maybe deeper than the straight across ones I have.
This one is for sale locally and I'd like to use it if it's a relative bolt-in to keep pinion angle correct. (I know early cars use a different crossmember mount)

Crossmember bottom.jpg

Crossmember top.jpg

As opposed to the straight across version here:

Straight Late Crossmember.jpg

The car was previously converted to 3-link with a torque arm.... I'm trying to keep the pinion angle correct.... as it's controlled by the trans height.
I was thinking of modifying the ends of the later T-50 crossmember to mate up to the 72's early style body mounting ears.
OR
Maybe just bolting the late T-50 style crossmember (pictured first) to the floor of the '72 using reinforcement plates on top of the floor pan.... (if the floor pans in these locations are the same height???? ) I'd like simple bolt-in and not have to fab anything up.

Any ideas?

[Smiley]

It looks like a 76 and up 5 speed crossmember, it would need extending, extra floor reinforcement and shimming to work on the early cars.

For more of a bolt in the Power by Ace crossmember bolts to the 71 to 75 mount holes and then you drill 2 holes at the rear of the floor.
"Bolts to the original trans mount and reinforced section of floor pan. Available for V8, or V6, LSx with TH350, 700R4, 4L60/ E one or two piece case, 200R4 and TH400, 4 / 5 speeds (specify).
T56 Camaro / Firebird special order. After installation, cross member is removable for transmission R & R. Use #122268, 122672, 122288 cushion."

"Satin black powder coated. Part # 10530 $ 109.93
xmember brackets un welded, painted. Part # 10538 $ 99.93
Lower 48 States Shipping $ 17.90"

If you have a welder I would get the unwelded kit and set the location exactly where you want it with minimum fab work.






Early cars lack the trans mount brackets in the floorpan which hang down an inch or so below the thin single layer metal area of the floor on early cars.
later torque arm floor:


early floor:

[bugdewde]

Very nice examples. I'm sending these pics to my buddy (the welder) for ideas.
Really like that last one. Wish I had a reference for the correct height of the tailshaft.... I'd have one made up like that one.

The Power by Ace one would probably be more suitable for me, though...... as I'm literally out of spare T50s..... and will soon have to switch over to T-5s. I used to buy T50s for $50-$75 all day long. Most I ever paid for one was $100 from Mike Mitchell from back in the Bob Gumm forum days. It's still in the blue '73 hatchback.
That crossmember could be used with both trans , by simply moving the crossbar whereever it needs to go on the side rails.

Hmmmm.... ??? .... might be a good idea to use that idea with some subframe connectors. Dang it!!!!..... this is a driver, not a project!

Thanks for the info guys. I really appreciate your knowledge.

[Monza Harry]

Dwight if I read that right you still have a T50 in a car? If so you can just measure from some landmarks to get the height of your tranny in the new set-up. ie; straight edge across pinch welds and measure up to the tranny mount platform on the cross member. Double check from tunnel own top a feature on the top of the tranny, etc. I know you can find something under there. if you don't have a T50 installed measure what ever you have to the tail shaft, that height is what you are ultimately setting to get everybody playing nice! Harry

[bugdewde]

Yes, T50 in blue 73 hatchback. (late model trans in an early car with different mounting locations)
Problem is, I suspect it is wrong height also. That crossmember came installed on a previous 215-powered '72 Vega with a T-50 I bought back in '03. Granted, it has worked for years but either it or the matching driveshaft has had a nagging vibration. It appears to be an early style crossmember that has simply been lengthened. Doesn't appear to be modified up or down...... to compensate for the most assuredly difference in trans mount locations between the 4/5 speeds. Seems obvious the 5-speed trans mount sits lower than the 4-speed/auto .... with the pics I posted in the first post.
I plan on re-using them temporarily to get car operational. This will leave the blue hatchback inop until I can figure out correct tailshaft height..... possibly by your methods on another 5-speed car. They're kinda scarce around here.

[Monza Harry]

Dwight it doesn't have to be a 5 speed, it just has to have a transmission of similar length, to get meaningful landmarks from, I never had the 5 gear, so I'm unfamiliar with it's size, so you'll have to look that one up. I did a quick search a short while back and couldn't find the page I was looking for, with the length and mount distances. If I find it I will forward it to you and the board. As an example the THM200, THM250, THM350, and the Saginaw are all the same length, so the output shaft would be in the same spot, with out the mount necessarily being the same. If the shaft is right and the torque arm is too it will be back to factory settings. If you measure down from the tunnel make sure they have the same tunnel design though there at least a couple of designs remember. Harry (P.S. I can give you a call tomorrow if you want.)

[bugdewde]

Yeah, I can probably get close..... my tunnel has been significantly modified.

tunnel mods.jpeg

I can use the modified crossmember from the blue car and and get by.


I hope the torque arm will fit...... it appears to be too long. I thought I had a stock T-50 torque arm, but apparently I don't.

Torque Arm up.jpeg

Car is at my buddy's shop, and I work the next 4 night shifts so it's just gonna sit a week or so until we can get back at it.

[bugdewde]

Here's the info I've gotten off the h-body.org FAQ:
Section 10.5 of Transmission swaps.
T-50:

Robert (twelve_second_vega) writes:
"Keep in mind the T-50 is almost 4" longer overall than a Saginaw and the Mount Pad is 3" farther rearward too. The Driveshaft and Torque Arm are unique also. There are basically (3) driveshaft lengths in the "H" Body cars (measurements are tube length only from weld to weld):

4 Cylinder with Automatic or Saginaw: 46 1/2"
V6/V8 with Automatic or Saginaw: 42 1/4"
V6/V8 with T-50 Transmission: 39 3/4"

The V6/V8 Torque Arm bears the numbers "5343" and the V6/V8 with T-50 bears the numbers "5353".

The distance from the Bell Housing mounting Surface to the Centerline of the Transmission Mount Bolt Holes are as follows: Saginaw: 14 1/4", T-50: 17 1/8"

Your 1977 chassis has (2) sets of holes for the Transmission Crossmember and you would use the rearmost holes for the T-50."

I'll re-address this once I'm back under the car after my nightshifts.

[monzaaddict]

ttt