[TR] TR4 - TR6 front suspension

[Brad Kahler]

I'm trying to do an analysis of the front suspension dimensional
differences between the early TR4 cars and the TR4A and later cars.

Below are some assumptions that I've made:

The lower a-arms are the same from tr4 thru tr6. The upper a-arms are the
same from later tr4 thru tr6. The vertical links are dimensionally the same
except for camber/castor angle changes. I'm pretty sure the lower spring
pans are the same with probably only slight differences but I believe the
basic dimensions are the same. The upper fulcrums are the same just the
orientation changes between tr4 and later tr4 thru tr6.

Since the vertical links are the same overall length that should mean the
distance between the upper fulcrum pivot point and the lower a-arm pivot
point (on the frame) should be the same for all models. With all of that
being said that tells me the installed spring height from the lower spring
pan seat to the upper spring seat should be the same for all models.

I'm betting the overall front end weight is pretty close between the 4 and
6 cylinder cars as I've read that the stock spring rate between 4s and 250s
is only about 2 pounds (310 vs 312)

So my unless I'm missing something then springs that are 10.1 inches tall
from a tr250 should fit in a tr4 that originally had 9-3/4" springs and a
1-1/4" packing piece. In other words the 10.1" springs (and no packing
piece) should be a direct swap for the 9-3/4" spring it its associated
1-1/4" packing piece.

Anyone see any holes in my logic?

Thanks!

Brad