Transmission Ratios

tjm73

Founding Member
Aug 3, 2000
2,418
1
48
Rush, NY
I asked a question once about tranny ratios and no one knew the answer so I did some more research and found my answer. I figured I'd post the info in case any one else ever needs it. If anyone has any other ratio's or transmissions to add, please do.

T5 5 Speeds:
1987-93 5.0 T5 – 3.35/1.99/1.34/1.00/0.67
Z-Spec FRPP T5 – 2.95/1.94/1.34/1.00/0.63
G-Force Modified T5 – 2.94/1.94/1.34/1.00/0.59 (OR 0.73) Good for roughly 600hp/500 ft/lbs in 3300 lb car

4 Speed Top Loader:
Close Ratio –2.32/1.69/1.29/1.00
Wide Ratio – 2.78/1.93/1.36/1.00

3 Speed Top Loader Manual:
RAN 3 Spd– 2.99/1.75/1.00 (I6 and small block V8)
RAT 3 Spd Manual – 2.42/1.61/1.00 (big block V8)

Automatics:
C6/C4/AOD Automatic– 2.46/1.46/1.00 (0.68 OD in AOD)
4R70W Automatic– 2.84/1.55/1.00/0.70
 
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Stock Stock WR Stock WR E4OD
C4 C6 C6 AOD AOD

1st 2.46 2.46 2.72 2.40 2.84 2.72
2nd 1.46 1.46 1.54 1.47 1.55 1.53
3rd 1.00 1.00 1.00 1.00 1.00 1.00
4th ---- ---- ---- 0.67 0.70 0.71


1984 85-86 1983 1984 85-89 90/SR WC TR TR
SVO T5 SVO T5 T5 T5 T5 T5 T5 3550 3750S

1st 4.30 3.50 2.95 2.95 3.35 3.35 2.95 3.27 3.18
2nd 2.37 2.14 1.94 1.94 1.93 1.99 1.94 1.99 2.06
3rd 1.50 1.36 1.34 1.34 1.29 1.33 1.34 1.34 1.39
4th 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
5th 0.76 0.78 0.73 0.63 0.68 0.68 0.63 0.68 0.65


WR CR SROD SROD BW BW RG RG RG BW
TL TL cast alum T10L T10M 4+1 ROD ROD T56

1st 2.78 2.32 3.29 3.07 2.36 2.36 3.27 3.27 3.01 2.97
2nd 1.93 1.69 1.84 1.72 1.76 1.62 2.13 2.13 1.88 1.94
3rd 1.36 1.29 1.00 1.00 1.41 1.20 1.57 1.57 1.46 1.35
4th 1.00 1.00 0.81 0.70 1.00 1.00 1.23 1.23 1.19 1.00
5th ---- ---- ---- ---- ---- ---- 1.00 1.00 1.00 0.82
6th ---- ---- ---- ---- ---- ---- ---- 0.76 0.62 0.62




http://www.mustangsandmore.com/ubb/DanJonesC4AODswap.html
 
I was wondering what ratios were available in the toploader overdrive tranny of the mid-70s...
3+1, 3 speed overdrive, whatever you want to call it.
I know I have seen at least 2 sets of ratios available, but don't remember them for anything.
Anyone got that info?
Thx
Dave
 
ratio411 said:
I was wondering what ratios were available in the toploader overdrive tranny of the mid-70s...
3+1, 3 speed overdrive, whatever you want to call it.
I know I have seen at least 2 sets of ratios available, but don't remember them for anything.
Anyone got that info?
Thx
Dave

I think you are reffering to the SROD which was available until the mid 1984 in V8 Mustangs. It was a 3 speed plus OD. Not particularly strong, but plentiful. One of my firends has one he would sell pretty cheap. I think he has the stuff that goes with it too. If anyone want's more info PM me.

And yeah the SROD info is in the list part way down.
 
ratio411 said:
Can you mix and match gears between like trannys?
I would love to build a toploader like so:
2.78
1.69
1.00
0.70

Top Loaders where never available with OD ratios. You can't just mix and match any of these gears. Many of these tranny's are totally different from each other.
 
tjm73 said:
Top Loaders where never available with OD ratios.
Oh yes they were...
I think that I am refering to a different tranny than the "SROD".
I know for a fact that Ford converted toploader 4 speeds to 3+od in the 70s. They were available in Granada/Monarch.
I have seen several with my own eyes.
Being an iron case toploader behind a V8, and often in front of a 9" rear, I don't see how they would be considered weak.
Dave
 
ratio411 said:
Oh yes they were...
I think that I am refering to a different tranny than the "SROD".
I know for a fact that Ford converted toploader 4 speeds to 3+od in the 70s. They were available in Granada/Monarch.
I have seen several with my own eyes.
Being an iron case toploader behind a V8, and often in front of a 9" rear, I don't see how they would be considered weak.
Dave

They are not true Top Loaders. They will grenade behind even mildly modified 5.0. Just because they were behind V8's and in front of 9" rear ends doesn't make them strong. V8's of that era were weak. The Mustang II V8 was only 145 hp. Some Honda Civics have more power than that.

Ford went to the T5 in mid 1984 for 2 reasons.
1.) Fuel economy concerns. T5 gave better acceleration and better fuel economy.
2.) Early T5's (known to be the weakest of the T5's) were stronger and withstood more powerful 5.0's that were coming off the production line.
 
nosaj122081 said:
Yeah, that's it.

I might be hard headed, but even though it is billed as an 'imposter' on that site, it is still a toploader with plenty of potential.
It might be weak compared to early toploaders, but some creative parts swapping should cure that.
After all, the TL 3 speed, 4 speed, and OD are on the same basic design and even the 3 speed is considered strong, yet is not a "performance" toploader as noted on that site.

This is all 'bench racing' anyway, I am sure that swapping bulletproof toploader parts into the OD would be more trouble than it is worth... but I like the idea that it could be done.

TJM: I wasn't trying to insult your intellegence by remarking that the tranny was behind a V8. Sorry.
I was just thinking about it being built on the toploader platform and being cast iron. Those 2 things are the foundation for the strength of this design when compared to any other (side loading) design. While Ford certainly would have skimpped on the internal strength, being the 70s, that could surely be rectified.
This is all food for thought.
If gas prices weren't so high, I would stick with a wide ratio and 4.11 gears.
Dave
 
ratio411 said:
TJM: I wasn't trying to insult your intellegence by remarking that the tranny was behind a V8. Sorry.
I was just thinking about it being built on the toploader platform and being cast iron. Those 2 things are the foundation for the strength of this design when compared to any other (side loading) design. While Ford certainly would have skimpped on the internal strength, being the 70s, that could surely be rectified.
This is all food for thought.
If gas prices weren't so high, I would stick with a wide ratio and 4.11 gears.
Dave

No man, I'm not insulted. I do question them being built on the same platform though. The Single Rail Over Drive (SROD) 4spd looks completely differetn from the early Top Loader 4 speeds. If they are in fact built on the same platform and could be made stong enough, then it would make a nice OD option tranny.

EDIT: I'd use one for a Ford powered street rod project I'm gearing up for if it were stronger.