Big block, early a transmission mount

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TurboBBscamp

TurboBBscamp

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When I put a 440 in my scamp I used the slant 6 transmission crossmember/mount with no issue or mods. Now I’m mocking up a 440 in my 65. I have the tunnel clearanced but I can have the tail shaft touching the upper crossmember and the mount holes are about an inch from lining up. Just curious where the difference is between the 2 bodies and/or the early/late slant tail shaft before I start modifying the mount. Thanks!
 
Your question is a bit confusing. What exactly do you have parts-wise? Are you using an early A crossmember? What transmission? If you've got the early A-body crossmember, it should work with with zero problems. Is your 440 mounted? Maybe it's not where it's supposed to be front to back. With the engine and transmission bolted together, hang them in place and use the transmission crossmember to locate everything fore/aft.
 
440/727. Elephant ears from the scamp that I narrowed to fit. Stock 65 crossmember/mount. Fore/aft no issue (haven’t made mountng tabs yet). I expected it to work fine, but the crossmember is an inch away from lining up and that’s with the tailshaft touching the upper crossmember. Comparing the early and late crossmember, the late one does have more drop in it (about what it needs) but obviously has a wider bolt pattern.
 
The early A-body crossmember should work fine with a 727. Many folks have 727's in their early A's using the stock crossmemeber and mount (myself included). There's something else going on. Can you post a photo of the interference?

What's the 727 out of? Maybe there were some variations in 727 extension housings? Does it have an oddball mount or something cast in the top of it that's contacting the upper crossmember?
 
mopowers said:
The early A-body crossmember should work fine with a 727. Many folks have 727's in their early A's using the stock crossmemeber and mount (myself included). There's something else going on. Can you post a photo of the interference?

What's the 727 out of? Maybe there were some variations in 727 extension housings? Does it have an oddball mount or something cast in the top of it that's contacting the upper crossmember?
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So an inch was a bit of an exaggeration, but it’s a hole off. There is a piece of rubber above that would allow it to line up but still closer than I thought it should be. No oddball stuff. Maybe the rubber mount is swelled up? Best I can do for pics right now

IMG_1904.jpeg


IMG_1905.jpeg
 
TurboBBscamp said:
So an inch was a bit of an exaggeration, but it’s a hole off. There is a piece of rubber above that would allow it to line up but still closer than I thought it should be. No oddball stuff. Maybe the rubber mount is swelled up? Best I can do for pics right now

View attachment 1716111666

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There's definitely something going on with that mount. It's either too tall or not fully seated in the crossmember. Is there anything hanging it up? Maybe it's just the wrong mount?

I just checked mine and the distance between the top of the crossmember and the surface where the mount bolts to the transmission is much shorter - like half that length.
 
Thanks for looking! I think thats what i need to hear. It's definitely seated. I just pulled the slant so I can only assume it is correct and pretty sure its original. Starting to think maybe it is swelled and the slant tailshaft was probably pushed up against. I guess my next step is to get a new mount (which I wouldve replaced anyway) and see how they compare.
 
TurboBBscamp said:
Thanks for looking! I think thats what i need to hear. It's definitely seated. I just pulled the slant so I can only assume it is correct and pretty sure its original. Starting to think maybe it is swelled and the slant tailshaft was probably pushed up against. I guess my next step is to get a new mount (which I wouldve replaced anyway) and see how they compare.
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Let me see if I can get a decent picture to compare yours to. Mine's just a stock replacement mount.
 
Here's what mine looks like. Apologies for the poor lighting. It does look 1/2" or so shorter than yours. The top side is pretty tight. I don't use the rubber bumper on top and there appears to only be about 1/4"-3/8" clearance at the peak.

1688772172627.png
 
mopowers said:
Here's what mine looks like. Apologies for the poor lighting. It does look 1/2" or so shorter than yours. The top side is pretty tight. I don't use the rubber bumper on top and there appears to only be about 1/4"-3/8" clearance at the peak.

View attachment 1716111738
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Thank you thank you thank you! That pretty much answers it. Whether it’s the correct mount or not doesn’t matter, something isn’t right with it. Thanks for not letting me do something stupid and start cutting and welding. I knew in my heart it shouldn’t have been an issue.
 
TurboBBscamp said:
Are those studs and nuts oem or did you do that? I like it
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Good question. I actaully have no idea if they're OEM. The studs were in place when I got the trans from a buddy of mine, so I just left them in when I rebuilt it. I had to reference an old photo I took to refresh my memory. Let us know when you get a new mount. I'm curious how much shorter it is than your current mount.

1688774924725.png
 
mopowers said:
Here's what mine looks like. Apologies for the poor lighting. It does look 1/2" or so shorter than yours. The top side is pretty tight. I don't use the rubber bumper on top and there appears to only be about 1/4"-3/8" clearance at the peak.

View attachment 1716111738
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Huge difference! The plate the rubber mount sits on is completely inside the cross member. That will make the difference for him!
 
TurboBBscamp said:
Thank you thank you thank you! That pretty much answers it. Whether it’s the correct mount or not doesn’t matter, something isn’t right with it. Thanks for not letting me do something stupid and start cutting and welding. I knew in my heart it shouldn’t have been an issue.
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Is your mount one stud on the bottom or two?
 
mopowers said:
Good question. I actaully have no idea if they're OEM. The studs were in place when I got the trans from a buddy of mine, so I just left them in when I rebuilt it. I had to reference an old photo I took to refresh my memory. Let us know when you get a new mount. I'm curious how much shorter it is than your current mount.

View attachment 1716111768
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I will definitely try. Maybe the group will like a build thread. I started one with my slant turbo build but forgot to update it
 
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