Yeah this truly IS a huge mess.
Everything is wrong, except one thing; the 3.73s are right, for a manual trans, and that 236/244/110 cam. . Anything less, with a low-cylinder pressure, small-cube engine, is gonna be sluggish; especially in a heavier car.
The first thing you gotta do is a compression test. and
the Second thing is to get your speed-o and tach sorted out; one of them is a big fat liar. and
the third thing to do is get rid of that 236/244/110 cam.
It's not a bad cam; it's just way too much for a 318, in that car. To properly use it, the 318 would need about 10.3 or better compression ratio. And since the power peak of that cam is up around 5400, the torque peak could be as late as 3900 . That cam may want to be upshifted another 300 to 500 over the top,so say 5800, and best performance will then be in the rpm range of 3900 to 5800.
Ok now; estimating a tire diameter of 26.5=83" roll-out,
and with 3.73s, and a standard 2.66 low A833;
3900 in first is 31mph when the cam wakes up.
and 5800=46 mph when it's time to catch Second.
And second will hit 5800 at 64 mph.
So, 3.73s are the right gear for this cam.
Therefore, if you have a 10.3 or better compression ratio, or 155 to 160 psi cylinder pressure, then you have a great combo, just too small for the weight of the car.
But
if you have an 8/1 Scr engine, your pressure is gonna be less than 120 psi, and take off from a stop will feel like a slanty; sluggish? Ohyeah bigtime sluggish!
BTW;
with 26.5s and 3.73s; 65 =3085 / 55=2610.
60 mph = one mile in one minute, and is 2840 rpm
Oh and Don't even think about running an od box in that combo.
BTW, great looking car!