Small block to big block trans cross member doesn't work after swap?

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Minnesota Muscle

Minnesota Muscle

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So I purchased this car with out an engine. The trans was still installed. It was a small block 727. So I took my motor home big block 727 and had it rebuilt and used the tail shaft off of the small block trans.

When I go to bolt it up, the cross member only goes one way, but the body of the trans/bell housing hits the firewall and the tail end of the trans is tipped too far upward to get the driveshaft on, let alone in operating position.

I loosened up the two bolts that hold the round rubber mount to the trans and that gave me a little play, but it's still not close. The round rubber mount comes off the transmission and angles back towards the tail end.

So take a gander at the photos, what's not right? The cross member will only bolt up one way, so that's not adjustable, and the round rubber mount is already angled the direction it would give me the most clearance. I've read all the cross members were the same so what gives???

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I'm starting to wonder if someone cut this cross member up and modified it. I can't find a picture like it searching online. This is on a 1967 barracuda.

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Plus I just measured the circumference of the small block bell housing vs the big block bell housing and sure enough the big block is larger, which is what is causing the clearance issue with the small block 360 cross member.

I thought I had read multiple times that all the cross members were the same, measurement wise.

So now I need to know what guys are using to bolt a big block 727 in an A-body....?
 
Minnesota Muscle said:
That mount appears to be just the right amount "forward" that I need. I need an inch to about an inch and a half forward movement from what I have.

What is the second part that would mount to the trans itself?
Click to expand...
A trans mount
This is the pre 73 style
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Yours is the '73+ spool type
 
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Minnesota Muscle said:
That mount appears to be just the right amount "forward" that I need. I need an inch to about an inch and a half forward movement from what I have.

What is the second part that would mount to the trans itself?
Click to expand...
The factory mounts are all the same. Yours appears to be fabricated. A factory crossmember and mount would move everything forward the required amount.
Any '67-'72 will work.
 
Greatly appreciate your time.

So much for getting this thing together this weekend. I guess I could re-fabricate the thing...
 
After looking at a handful of them on eBay, it looks as though the last owner cut up and rewelded the four speed crossmember to make it work. (This car is a four speed car originally).
Shameful!
 
Sounds like your engine is too far back. Leads me to believe wrong motor mounts or installed wrong- too much set back.
 
I have the Schumacher big block to a-body mounts, but the engine isn't in yet. I was going to get the transmission installed and use it's location to help me understand where the engine mounts should bolt up.
 
Syleng1 said:
Sounds like your engine is too far back. Leads me to believe wrong motor mounts or installed wrong- too much set back.
Click to expand...

I never saw an engine in the car, it was long gone when he listed the car for sale. But I agree, I'm sure it worked for the smaller small block trans. I bet the clearance he had with the small block trans was similar to what there would be for the big block trans at the fire wall.
 
Minnesota Muscle said:
I never saw an engine in the car, it was long gone when he listed the car for sale. But I agree, I'm sure it worked for the smaller small block trans. I bet the clearance he had with the small block trans was similar to what there would be for the big block trans at the fire wall.
Click to expand...
So they came from the factory - BB and 727. No fire wall changes so this leads me to believe since there is no engine in the car yet that the trans mount is wrong. Try hooking up the shifter rods and see if they are even close to verify. (I’m assuming they are with the car still?!?) all that stuff should be in the normal location. Maybe more info on what was done to the transmission? Was that an RV drum tail shaft converted to 727 car tail shaft?
 
Syleng1 said:
So they came from the factory - BB and 727. No fire wall changes so this leads me to believe since there is no engine in the car yet that the trans mount is wrong. Try hooking up the shifter rods and see if they are even close to verify. (I’m assuming they are with the car still?!?) all that stuff should be in the normal location. Maybe more info on what was done to the transmission? Was that an RV drum tail shaft converted to 727 car tail shaft?
Click to expand...

Unfortunately it's been converted to a cable driven floor shifter, no linkage at all being a manual shift valve body.

Yep, took the RV trans and used the car tail shaft off the small block trans. I'm not sure what you mean by a drum tail shaft, but it was substantially shorter than the car one. I have all the parts still and could post a picture of you needed.
 
There are at least four types of 727 2wd tails. 1....The "flange drive" rear tail used in passenger cars through 64, 2......the standard long shaft used in light trucks and all passenger cars 65 and after, 3, the "short shaft" tail used in some motor homes, and 4, the type(s) used with a drum brake emergency brake installed on the rear of the tail housing

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Yup- the top picture is what I was referring too. Thanks #67Dart273 . You explained that perfectly!
 
oldkimmer said:
What do u have for motor mounts on the K frame and bolted to the motor. Post some good detailed pics. Kim
Click to expand...

Like I mentioned before, engine is still out of the car. I'll get some pictures posted when I get it ready to drop in. Should be this weekend. I'm going to fabricate that trans mount to work, then replace it with the proper one when it arrives.
 
The 67-62 and 73-76 crossmembers all interchange to a certain extent. Only difference is the 67-69 cars used larger 1/2 inch bolts. 70 up cars used 3/8s bolts. So a little modification is in order. U may also have a truck mount bolted to ur crossmember and I believe they are a little taller than a car mount Kim
 
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