Wedge early/late tr7 differences

[philman]

i decided to replace the ball joints on my '76 fhc and ended up having to drop the cross member to pull off one of the lower control arms. just for fun i lined it up next to the cross member off an '81. it looks like the engine lays over more on the later cars.

so does this mean that to use this cross member on my fhc that i would have to also change over to the 5 speed transmission and rear axle?

i have all the components to do this, but the four speed seems a more spirited driver than the five speed in my '81 was.

 

[Mickey Richaud]

Hi, Philman -

According to the Rimmer's catalog I have, there was a change in the crossmembers for '77. I assume that was due to the changeover to the five speed at the time. In Piggot's book he mentions the difficulty in swapping a five-speed into an earlier car, so maybe this was one of the factors.

I'll be curious to hear what more you find out.

Mickey

 

[tr8todd]

I never noticed a difference between the two, but to be honest, most of my experience is converting them to TR8 subframes. This requires grinding off the TR7 lower engine mount and adding the TR8 engine mounts. In the past, I have converted a couple of four speed cars to five speed cars without changing the subframe. If it looks like a big difference, I suppose you could cut a reweld the mount where it needs to be. TR7 subframes are plentiful and can be had for about $50.00. If you want to keep the much weaker 4 speed stuff, perhaps it would be better to just score an early subframe.

 

[philman]

on the newer cross member the left motor mount is different, the rubber mount on the newer mount sits lower, so you would have to change the bracked that fastens to the oilpan which seems to set the motor at the right angle and height. the newer cross member also has no bracket for fastening the torque strut used on the left side of the older motors. but since the newer motors omitted this is it really necessary? I have photos of the old and new cross members and motor mounts side by side i'll upload soon.

i decided to try the newer cross member because somebody had previously done a poor job of repairing the older crossmember. i'll see if it is a direct swap out. oh, i stayed with the four speed. i decided that if i was to convert to the 5 speed i'll go ahead and put in my 3.5 liter engine also. but that project is three cars down the line.