MarinaCoupe wrote:Good research Bryan,
BL blunted the torque and power of the 2.0 litre Ital with the auto box (side stepping the manual gearbox problem), and protecting the back axle in the process. Also by keeping her as a single carb they could strangle the O series potential.
The Marina box was originally designed for the 1200 Triumph Herald, the updates helped but essentially the basic main bearing sizes and gear set dimension were defined in the late 1950s / early 1960s.
The TR7 went from the same gearbox to the LT77 as the Triumph engine was pushing out 135 lb/ft of torque and needed a more capable gearbox as well as a fifth gear.
I didn't know the early TR7's shared the same 4 speed box??? I knew the rear axle was a commonality, though.
Nic and I had a TR7 for a bit 2 years ago with the original 2.0 slant four up front. We put 3k on the clock in the space of about 4 months and I will admit that they were 3000 HARD miles.
She blew an exhaust manifold gasket but never had any 'box trouble?I'm not a fan of the LT77 box at all. It manages to have a sloppy and notchy gearshift action all in one which is something of an "accomplishment".
I do recall our '7 being a bit harsh on the motorway. So perhaps it'd be worth going for a taller diff ratio to quieten things down a little bit. If nothing else, the extra grunt will negate the power loss from taller gearing.
*edit* found a picture of the '7. Not bad for a really early car - incredibly shell. original sills and everything. It went to a nice chap who had plans to V8 it.
Much like the marina, TR7's are massively under rated cars. Again, much like the marina, a bit of work on the suspension - dropping the suspension an inch, some decent shocks and an anti-dive kit transforms it from a bit of a jelly to a propperly planted sports car.
What on earth were BL thinking to turn all their cars out with really soft suspension? It really was a case of nine tenths there with so many products.
