Wanted to say thanks to the folks who sent me scans of the drawings of the
I started laying out the lines in CAD and decided to import the scanned
drawing of the frame into the background.
(Basically I was trying to see if the drawing in the Bentley manual was a
scale drawing or not)
Once all the appropriate panning and zooming was complete, I was surprised
to see that some of my lines weren't quite matching up with the picture in
Once I looked at it a bit closer. . . I think I may have found out what is
My suspicion is that the drawing in the TR4 manual is actually of the TR3
frame and only the values in the table were changed to reflect the TR4
Anyone have detailed knowledge of the differences between the TR3 and TR4
I know the TR4 is 3" wider. I assume that they didn't just extend the
"outriggers" (where the floor pan attaches, out by the rocker panels)
Did they actually increase the spacing between the box sections running the
length of the car?
According to the TR4 chart I have, at the back of the car, the box sections
are 30" apart at their outer edges (dimension #31 = 15" x 2)
At the front, up by the radiator mounts, it looks like the box sections are
15" apart at their closest edges (dimension #5 = 7.5" x 2)
The motor mount holes appear to be 16.92" apart on the TR4 (dimension #9 =
8.46" x 2)
Anyone care to look up the matching dimensions on a TR3 frame and see what
they are listed as?
1970 TR6 Everyday