Thinking outside the box
A999 and 3.55s and a tad more TC
Your current combo, has road gears of 7.91-4.68-3.23
The above combo will get roadgears of 9.73-5.47-3.55
That is 23% more torque multiplication in first,16.9% more in second, and 9.9% more in direct. The A999 has a lock-up making the cruise rpms very similar.
Now, the first gear at plus 23% ,will make your 273 feel like it just grew 63 cubes. And second gear, at plus 13.9%, will make your 273 feel like it just grew 46 cubes, and direct like 27 cubes.
And we haven't even factored in the TC yet.
Outshifting at 5000, first will get you about 37 mph. Second will be about 66mph, and third about 102mph. 65 =3046. All calcs are with 25.5 tires, and 5% slip.
Factor in a 2800TC and this will be rapid transit.
Time spent? Less than one day with just swaps.
Cost ? probably less than $400 for cores, plus the gears,TC, and rebuild kits
Total? I'm guessing $1500
Now, go back;
The 273 if operating at about 1.06 ftlbs per cid is gonna put out about 290 ftlbs. Probably at about 3500rpm. With the new gears, this will be 2821ftlbs into the rear axle@ 26mph
A stock teener by contrast also putting out 1.05 ftlbs/ cid, will muster 334 ftlbs, probably at 2800ish rpm. With the current gears, this will be 2643 ftlbs into the rear axles @at 27 mph . So the 273 wins with 6.7% more torque into the rear axles at 26.5 mph.
And we haven't even factored in the TC yet.
Lets look at second gear. First the 273. At 3500rpm she will be doing 46 mph and putting down 1585 ftlbs into the rear axles. And the teener at 2800 will be doing 43 mph and putting down 1564ftlbs. Now they are neck an neck.
Third is past the speed limit, so who cares. But if you really want to know; the 273 will be doing 1029ftlbs @3500/71mph, the teener
