Are the front cross members and motor mounts the same on a '73 as a '79? I have a '73 2wd that I put a 351w in and bought headers for a '79 302 and they don't fit???? The motor mounts are in the way.

 

I am not sure I am following you. You have a 73 2wd with a 351W. You puchased a set of headers that was supposed to fit a 79 302/351? Was the 79 headers for a 2wd or 4wd...there is probably a difference if so. I would think the crossmembers on all 2wds and motor mounts from 73-79 are the same. I recently had a set of 302/351 mounts pulled from a truck in the junkyard, although I am not sure what year, and they bolted up perfectly to my 73 crossmember. I have a 73 2wd and I used Mustang shorty headers and they clear with no problems.

 

They were for a 4wd and they hit the motor mounts, they are long tube headers,I actually bought the same ones for my old '86 Bronco that had the 5.0. So are the front cross members different from a 4wd frame to a 2wd frame? If the cross members are different it could position the mounts different also.

 

4wd and 2wd frames/crossmembers are different. I've got some illustrations if I can get them into the correct format to post.

 

How about this - below is a pic of the 4wd crossmember in my truck.

It might be a little hard to see from the pic, but if you look at your 2wd you can see the major difference between the 2. The motor mounts on these bolt to the side of the frame BEHIND the cross member - about where the T-shirt/rag is thrown over the driver side frame rail.

 

Just my .02 but the problem could be that it's because the 351 is wider than the 302, and I don't think Ford offered 351W in the the 73-79 tucks (I could be wrong on that though). So the angle of the tubes come off the flange are different between the two. Summit does have two different part numbers listed if you search for a truck with a 351w and then change the search for a truck with a 302. Other than that the 4wd crossmember is a lot smaller than the 2wd one as shown in chase truck's pic.

 

So is the entire frame different or just the cross members? Because my steering box is behind the cross member and I thought the later '78-'79 where in front? I don't know about the earlier 4wds.

 

Front clip I think is different around the crossmembers forward. Crossmembers, tranny mount are different for sure.

ChaseTruck754's picture has an additonal brace in the very front because it is an F250...that you also will not have.

 

Early 4wds like mine have the steering box in front of the cross member. They are where the one in my pic above is - although the one in the pic is a 2wd box the P.O. put in there.