I have a 72 Ranchero. What I want to know is: Did ford use the SAME trans crossmember for the 351/C4 combos and the 429-460/C6's, or are they different? I know there are 2 sets of holes on the frame for either, but really I want to know if there is a difference. I am *hoping* they are, since my crossmember (from a C4) doesnt go up high enough in the arches to let the dual exhaust through. Thinking that a BBF/C6 may have higher arches. Thanks
My '71 Ranchero came with 351C & C6. The crossmember on it has room for dual exhausts, (I have 3 1/2" pipe from headers on it now). Also changed to a C4, just moved crossmember to other holes. Hope that helps.
do you have a 351W or 351C? i didn't think any came factory 351/C4? it would've been an FMX. i've had a handful of 72 torinos and rancheros, and stripped a few more cougars and montegos but no 429/460's. all were 351's. all crossmembers were the same, and i've never heard of a different one for different engine/trans combos. what exactly do you have going on that your exhaust is too high to go through the humps? i have a 351C/C6(was FMX) with 4V 1 7/8" supercomps that go right through the humps. i've had Casler headers, and some 2V's that also fit fine. from just sitting here trying to guess, the only thing i can think of is if you have a 351W with 302 headers, they will end too high. same thing if you have a 351M and Cleveland headers, the difference in the deck height of the engines will set the headers higher in the chassis. so what's going on?
Thanks for your input. Here is the situation: The Ranch came with a 351C/C4 setup. I dropped in a 460/C6. There is only 1 header that fits this app (Hooker 6126). The headers come down and end about 1 1/2" before they get to the crossmember. They are 3" header collectors running to 3" straight pipe. I need either the headers to go down (kind of impossible) or the x-member to go up. There is not room to bend the exhaust pipe (been to 3 different shops). I am using the C4 x-member that came with the car. So, I am wondering if the Big Block/C6 combo had a different x-member with HIGHER arches for the exhaust to get through. As of now, I had to severely cut the x-member to get the exhaust out, and it has weakened the structural integrity of the beam.
I went with Crites. They fit the frame and the block pretty well. If anything, I think they may have lowered the motor. I had to bang on one header to get it to clear the frame. I cant imagine that stock mounts (which seem to be unavailable) could lower it further.
Just looked at my 72 Ranchero with 400/C6. The trans cross member seems to have a about a 2-3 inch hump where the pipes go under. Now I had a 69 'bird and as I recall the trans x-member was completely flat no humps, can you go over it?...but then you're looking at ALOT of heat on the floorpans. Can you turn it over? That's a long way back for headers to go. The collectors would be at the trans pan! I was looking at putting in a 514 but this makes me skeptical. hope this helps