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Discussion Starter #1
Hey feelas- I am puuting a 700R4 into my 34 Olds coupe and have a question about mounting it up. The original frame is pretty beefy and has an X member in the center of the frame. There is just about 14 inches between the two sides of the X member at the tranny mount holes and it looks like I am going to have to fabricate a cross member to mount it up. The question is this- How much torque is likely to be placed on the tail end of this transmission and can I get away with a cross member that just sits between the X member rails or should I extend the cross member all the way out to the frame rails? I'll be running a 450 hp small block and won't be racing the car but I will likely drive aggressively at times. I look forward to your thoughts on the subject. Thanks in advance. Mike
 

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There is a lot more torque at the motor mounts than the tranny mount. Unless, of course, if the motor mount breaks.

How solid is the "X" part of the frame?

If it flexes at all, you should beef it up too.
 

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Rebuilt Excitment
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I left the factory x-member in my 36 Pontiac and am running a 200R4 transmission, It just fits both length wise and width. The 700 is somewhat longer, so you may have to redesign the x-member similar to the way that they do the Ford x-member from 35 up to 48.
 

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Discussion Starter #5
Thanks for your thoughts guys. The X member is pretty rigid and doesn't flex at all. It isn't as heavy duty as the frame rails are but very close. I have the tranny positioned where I need it and the tail shaft comes to just ahead of the crossing point in the X member and there is plenty of room for the drive shaft in the tunnel. I'll fabricate a sturdy tranny mount this weekend and see how she sits. Thanks again. Mike
 

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Now if I could just afford Gas
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Fatmanfab

I believe Fat Man Fabracations sells them for your exact car and transmission.
 

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Discussion Starter #7
Thanks Cole- I don't know why I didn't check into Fatman Fabrication earlier. I had them build my front clip with their Stage II suspension and should have check with them first thing. I'll give them a call on Monday. Mike
 
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