Back to the original point & post: my .02:
1. I don't really buy the 'original looks' argument. Most 5 speeds now have
an 'original look' shift handle available and the only way to tell would be
the top of the knob (shift pattern) or a look under the car; and it is far
easier to spot a replica than climbing underneath!
2. The 5 speeds (TKO500=95 lbs) tend to be lighter (barely) than a
toploader (98) [Trans ONLY: loaded the tko's are 105lbs, TL 109]
3. The 5 speed can keep the engine in a lower rev ban, saving stress and
expense both during engine build and general economy (gas).
4. Performance of the 5 speed will match a toploader AND give decent
cruising. I own a '66 GT350 and the little 289 really hums with 3.89 gears
on the highway! Storing the 4 speed and installing a T5 WC made the car
MUCH more driveable and enjoyable.
5. A close ratio TL ratios are: 2.32/1.69/1.29/1 and the tko500/600 are:
(500 ) 3.27 1.97 1.34 1.00 0.68
(600) 2.87 1.89 1.28 1.00 0.82
(600) 2.87 1.89 1.28 1.00 0.64
6. Final drive ratio is the key! : Buying a TKO600 and installing a 5.36 rear is
nonsensical. IMHO; follow the lead of Shelby and use a .64/.68 OD; so
3.54 FDR (mainly street) or 3.73/4.11 (competition).
7. RPM @ 70, using 295/50R15 (26.61" tall):
3.56 FDR: TL: 3129 rpm; TKO (.64) 2015 rpm; (.68) 2139
3.73 FDR: TL: 3297 rpm; TKO (.64) 2112 rpm; (.68) 2245
8. Note that the 3.73/.68 will give (IMO) the best overall performance--great
acceleration AND nearly 1k less rpm than the 3.56/TL combo @ 70!!
9. Final consideration is the engine build itself. Did you build a 8k screamer or
a 6000 rpm street engine? Ideally,the trans you install wants to keep the
engine in its' powerband as much as possible--not over the cam limit and
not lugging. I suggest looking at your cam specs and playing with a
calculator like this:
Tire Size, RPM, Speed, and Differential Ratio Calculator
/?ratio=2.54 to figure it all out.
10. Good luck and happy driving!
