I am planning on upgrading my Richmond 5 speed manual transmission (1:1 5th gear) to an overdrive manual transmission. There are several points to consider, Cost, Durability, Installation and Gear ratio's. My rear gear ratio is 3:23.

Tremec has two transmissions that I am considering, the T56 and the TKO 500. Richmond also has two, the 5 and 6 speed overdrive units. Automatic transmissions are not an option for this project. After the installation is complete I will be selling my current Richmond 5 speed (rebuilt) and hopefully I can recover some of my costs.

TKO 500
$2095.00
500 lbs. tq.
.68 overdrive
minor shifter modifications required

T56
$2595.00
450 lbs. tq.
.80 and .62 overdrive
speedometer, shifter, parking brake cable & pulley and crossmember mount modifications required

Richmond ROD 5 speed
$3595.00
600 lbs. tq.
.77 overdrive
crossmember mount modifications required

Richmond 6 Speed Overdrive
$3095.00
600 lbs. tq.
.76 overdrive
crossmember mount modifications required

I love the gear spread on the aftermarket T56 but it has the lowest tq. rating and needs the most modifications to install. What would you choose and why?

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First, how much torque do you figure to put to it?

TKO 500,...
Cost
minor mods
mid range OD

Or the R-6sp,...
Higher torque rating

 

Hi DeeVeeEight, good to hear from you again.
Seems like the TKO500 is the least expensive so I might be tempted to go with that one.
Not that a crossmember or speedo or parking brake mod would stop me.
What about the bell housing? Can your headers still fit?
You like to go to the track once in a while, it might be best to talk to some owners and see what they put in.
You say you like the T56 too, what benefit, in your oponion, does one have over the other.
Is one geared for better ET's or do you need more OD for that Sunday cruse?
"Automatic is not an opion". I hear you loud and clear on the one, stick shift is much more fun!
Last point, every $2500.00 project ends up costing about double.
Good luck on whatever you decide.
PG.

 

I LOVE the idea of the T56, 4th gear is 1:1, 5th gear is .80 and 6th gear is .62 - so you have the benefit of a hi/low overdrive set of gears. The .80 overdrive is attractive, the .62 is a little too tall but could be fun on a long trip.
The T56 has more modifications needed to git er done but they are not overly prohibitive.

The TKO 500 has a 5th gear of .68 - again a little on the tall side but useable. The TKO 500 is available in C3 kit form with an offset shifter and slip yoke for the same money as the (bare) T56. Installation is less of a challenge than the T56.

At this point I have pretty much eliminated the Richmond transmissions mainly based on cost and mod's needed to install.

My main goal at this point is to make the car more streetable and user friendly on the highway. I have been to the track a few times and I know I have a low 13 second street car. That is more than enough to get me into trouble on the street. My problem is on the highway, 3000 RPM @ 70 MPH with headers, dual exhaust and Flowmaster mufflers will make you DEAF in no time, plus the vibration and heat issues. Reducing my cruising RPM's by 700 or 800 RPM's will make a long ride more enjoyable - and there is the added benefit of less wear and tear on the engine and better gas mileage.

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