Transmission Ratios : 1
| Transmission/Gear |
1st |
2nd |
3rd |
4th |
5th |
6th |
Reverse |
| Powerglide |
1.76 |
1.00 |
- |
- |
- |
- |
1.76 |
| Powerglide |
1.82 |
1.00 |
- |
- |
- |
- |
- |
| TH200-4R |
2.74 |
1.57 |
1.00 |
0.67 |
- |
- |
2.07 |
| TH350 |
2.52 |
1.52 |
1.00 |
- |
- |
- |
1.93 |
| TH400 |
2.48 |
1.48 |
1.00 |
- |
- |
- |
2.00 |
| TH700-R4 |
3.06 |
1.62 |
1.00 |
0.70 |
- |
- |
2.29 |
| 4L60 / 4L60-E |
3.06 |
1.62 |
1.00 |
0.70 |
- |
- |
- |
| 4L80E / 4L80-E |
2.48 |
1.48 |
1.00 |
0.75 |
- |
- |
- |
| C4 & C6 |
2.46 |
1.46 |
1.00 |
- |
- |
- |
- |
| 727 |
2.45 |
1.45 |
1.00 |
- |
- |
- |
- |
| 904 |
2.70 |
1.54 |
1.00 |
- |
- |
- |
- |
| Borg-Warner T56 |
2.97 |
1.94 |
1.35 |
1.00 |
0.84 |
0.62 |
3.38 |
Overall First Gear Ratio :
1 (Tranny Ratio x Rear Gear Ratio)
This indicates the mechanical advantage your car will
have coming off the line - higher number is better (up to a point)
| Tranny/Rear Gear |
2.41 |
2.56 |
2.73 |
3.08 |
3.23 |
3.31 |
3.42 |
3.55 |
3.70 |
3.73 |
3.91 |
4.10 |
4.56 |
| PowerGlide |
4.24 |
4.51 |
4.80 |
5.42 |
5.68 |
5.83 |
6.02 |
6.25 |
6.51 |
6.56 |
6.88 |
7.22 |
8.03 |
| TH200-4R |
6.60 |
7.01 |
7.48 |
8.44 |
8.85 |
9.07 |
9.37 |
9.73 |
10.14 |
10.22 |
10.71 |
11.23 |
12.49 |
| TH350 |
6.07 |
6.45 |
6.88 |
7.76 |
8.14 |
8.34 |
8.62 |
8.95 |
9.32 |
9.40 |
9.85 |
10.33 |
11.49 |
| TH400 |
5.98 |
6.34 |
6.77 |
7.64 |
8.01 |
8.21 |
8.48 |
8.80 |
9.18 |
9.25 |
9.70 |
10.17 |
11.31 |
| TH700-R4 |
7.37 |
7.83 |
8.35 |
9.42 |
9.88 |
10.03 |
10.47 |
10.86 |
11.32 |
11.41 |
11.96 |
12.55 |
13.95 |
| 4L80E |
5.98 |
6.35 |
6.77 |
7.64 |
8.01 |
8.21 |
8.48 |
8.80 |
9.18 |
9.25 |
9.70 |
10.17 |
11.31 |
| Borg-Warner T56 |
7.16 |
7.60 |
8.11 |
9.15 |
9.59 |
9.83 |
10.16 |
10.54 |
10.99 |
11.08 |
11.61 |
12.18 |
13.54 |
Overall Second Gear Ratio :
1 (Tranny Ratio x Rear Gear Ratio)
| Tranny/Rear Gear |
2.41 |
2.56 |
2.73 |
3.08 |
3.23 |
3.31 |
3.42 |
3.55 |
3.70 |
3.73 |
3.91 |
4.10 |
4.56 |
| PowerGlide |
2.41 |
2.56 |
2.73 |
3.08 |
3.23 |
3.31 |
3.42 |
3.55 |
3.70 |
3.73 |
3.91 |
4.10 |
4.56 |
| TH200-4R |
3.78 |
4.02 |
4.29 |
4.84 |
5.07 |
5.20 |
5.37 |
5.57 |
5.81 |
5.86 |
6.14 |
6.44 |
7.16 |
| TH350 |
3.66 |
3.89 |
4.15 |
4.68 |
4.91 |
5.03 |
5.20 |
5.40 |
5.62 |
5.67 |
5.94 |
6.23 |
6.93 |
| TH400 |
3.57 |
3.79 |
4.04 |
4.56 |
4.78 |
4.90 |
5.06 |
5.25 |
5.48 |
5.52 |
5.79 |
6.07 |
6.75 |
| TH700-R4 |
3.90 |
4.15 |
4.42 |
4.99 |
5.23 |
5.36 |
5.54 |
5.75 |
5.99 |
6.04 |
6.33 |
6.64 |
7.39 |
| 4L80E |
3.57 |
3.79 |
4.04 |
4.56 |
4.78 |
4.90 |
5.06 |
5.25 |
5.48 |
5.52 |
5.79 |
6.07 |
6.75 |
| Borg-Warner T56 |
4.68 |
4.97 |
5.30 |
5.98 |
6.27 |
6.42 |
6.63 |
6.89 |
7.18 |
7.24 |
7.59 |
7.95 |
8.85 |
General Tranny Swap Information:
- TH375, TH350, Powerglide, TH200-4R, TH700-R4, and Muncie M21 all have the same 27-spline output shaft.
- TH400 has a 32-spline output shaft.
- TH350 and TH200-4R use the same yoke.
- TH700-R4 is 3" longer than the TH350 short
tail.
- TH700-R4's rear mount is 2" to the rear of
that of the TH350 short tail.
- Swapping from a TH350 short tail to a TH700-R4 will require shortening
the driveshaft 3".
- TH350, Powerglide, and M21 all have the same length and output shaft
spline count - therefore, no driveshaft mods required when swapping.
- TH350, M21, TH200-4R, and TH700-R4 all use the same tranny mount,
but TH200-4R and TH700-R4 use metric fasteners (M10 x 1.5 x proper length).
- Shims may be needed when swapping TH200-R4 in place of TH350 (or
any tranny swap, for that matter) for driveshaft phasing.
- Transmission mount or crossmember may need to be relocated fore
or aft for any given swap.
- TH200-4R and TH700-R4 have lock-up torque converters (from the factory)
and thus no top gear slippage when locked.
- M21, TH350, and Powerglide all fit the '68-'74 Nova without modifications,
and the TH400 should, too, since they were available from the factory.
General TH200-4R vs. TH700-R4 Information:
- TH200-4R has universal CBOP bellhousing bolt pattern, while the TH700-R4 has the Chevy only pattern.
- TH200-4Rs offers full-throttle upshifts into overdrive, while only '91 and later Corvette TH700-R4s offer this.
- When built properly, both trannys can withstand a lot of power! In the neighborhood of 650-700 hp.
- The 4L60 is the same as the TH700-R4. The 4L60-E is also the same, but electronically controlled.
- The best source for TH200-4Rs is from Buick GNs and T-Types.
- Non-lock-up torque converters are recommended for durability and to avoid some problems.
- Use only '87 and newer TH700-R4. They are much stronger than the early versions.
- Use only '86-'88 TH200-4R.
If you have any comments or questions, please e-mail me.
Copyright © 2005 Bruce Johnson and Craig Watson
