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Discussion Starter #1
New to the forum, if you're willing to give it I'm in need of some info about the Lenco transmissions, first and foremost the pressure when using air shift. Does it have to be exactly 150 psi and 250 psi respective to the version of the transmission? I'm looking at putting a six speed unit behind a 532 cubic inch, fuel injected big block Chevy with twin 76mm turbos, hoping to put out 2,600 horsepower at most, however as it'd be mainly a street driven car it wouldn't be on the full power tune all the time. I'm looking at either the Lenco or a 4l80e, my biggest concerning factor aside from cost was footprint given this would be in a makeshift transaxle setup and so it being overly long would adversely affect the footprint of this project. I don't want to do CO2 because of it being a street driven car and potentially being left stranded in whatever gear I'm in once the bottle exhausts itself, I'm going to do an onboard air system with either an ARB air compressor or, depending on shift pressures, a modified York 210 air compressor mounted to a single phase DC motor. Thanks in advance for any and all help.
 

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CS1 is obsolete so forget that.
CS2 from memory is 250 psi to the pods or get manual levers and drive it. If your on the street mostly then it would be the way to go.
Next is, running a Lenco on the street is not the best choice as it has no real oiling system and they wear quickly as that was not their intended place.
At 2600 hp, you may want to think twice about a 4l80e.

Maybe consider a T400.


Hutch
 

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Discussion Starter #3
The T400's a three speed if I remember right? As for oiling on the CS2 I could add a setup for a cooler with an electric pump mounted upstream of a junction block, might help with the longevity
 

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Yes you can. Do you think with 2600 hp that you will need a lot of gears? It won't take much throttle to start the tires on fire at any speed in any gear.


Hutch
 

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Discussion Starter #6
On my CS2 5spd I ran 150psi to the pods. 6 speed is going to be one long heavy transmission.
If the information I found is correct each CS2 case is just under 6.5" long and so a six speed would be 39" roughly outside however much is added from the reverser, haven't found any info on those dimensions yet
 

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Yes you can. Do you think with 2600 hp that you will need a lot of gears? It won't take much throttle to start the tires on fire at any speed in any gear.


Hutch
It wouldn't be running at 2,600 horsepower all the time on the street, I'm planning this around the max power the engine will put out and that's the mirror image turbos, I'm using such units for easier packaging. As for the number of forward gears it's going to be a six speed because I imagine it would help with acceleration and fuel economy when cruising.
 

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Discussion Starter #9
I get it, fuel economy is gonna be shit but every bit helps, hence why I'm going with closed loop sequential fuel injection and coil near plug ignition, better power management and easier to tune on the fly and therefore better fuel efficiency than a carb and distributor imo
 

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Have you tried turning a 6 speed CS2 with all the pods on or off?
I don't feel it meets the criteria of fuel economy or is 6 speeds required with 2600hp and a converter.
It is your project so go ahead. What will your gear ratios be and is it even obtainable with this trans?


Hutch
 

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Discussion Starter #11
Have you tried turning a 6 speed CS2 with all the pods on or off?
I don't feel it meets the criteria of fuel economy or is 6 speeds required with 2600hp and a converter.
It is your project so go ahead. What will your gear ratios be and is it even obtainable with this trans?


Hutch
I'm thinking the ratios if I do a six speed would be based off a wide ratio T56 Tremec, 2.66 first, 1.78 second, 1.30, 1:1, 0.80, and 0.63, and 2.90 reverse. What do you mean about turning the transmission? I haven't been around a Lenco in person let alone a six speed CS2 with air pods and a reverser
 

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There was a video on NHRA Today , with Steve Evans , when Pro Stock was switching to the 5 speeds . He showed a Lenco and how much drag it had when all the cases were shifted . By the time he got to 4th , he couldn't turn the input shaft . Not so with the 5 speed . Don't remember if it was a Liberty or not .
 

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You may want to look at the lenco ratio chart and see what's available. Overdrive won't happen and reverse is determined on which pods are activated.
The ratios you selected are pretty steep unless you plan to use a clutch.


Hutch
 

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Discussion Starter #14
You may want to look at the lenco ratio chart and see what's available. Overdrive won't happen and reverse is determined on which pods are activated.
The ratios you selected are pretty steep unless you plan to use a clutch.


Hutch
My plan was to go with a clutch, didn't even know that it was possible to use a CS2 with a torque converter. Overdrive not being a thing on Lenco's is gonna make me do some serious reconsidering about this.
 

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I have owned a few Lenco transmissions and if you do not have a good knowledge of them or somebody in your pocket that can put their hands on your project do not even consider one. They are excellent transmissions and very strong but they're very intricate in the tuning and operation of one. You would be better off using a gf5r G-Force transmission or a liberty 5-speed transmission. Don't add a bunch more spokes to the wheel if it doesn't need it.
 

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Discussion Starter #16
I have owned a few Lenco transmissions and if you do not have a good knowledge of them or somebody in your pocket that can put their hands on your project do not even consider one. They are excellent transmissions and very strong but they're very intricate in the tuning and operation of one. You would be better off using a gf5r G-Force transmission or a liberty 5-speed transmission. Don't add a bunch more spokes to the wheel if it doesn't need it.
What can you tell me about the air shift setup for the Liberty? May have found a second option outside the Liberty five speed, going to be doing more research on it but looks promising
 

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Air shifters suck for something that you are going to drive on the street. Unless you are an amputee go with the lever and be done with it. If you are class racing then go with CO2.
 

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Air shifters suck for something that you are going to drive on the street. Unless you are an amputee go with the lever and be done with it. If you are class racing then go with CO2.
Lever shift would be a problem with the transmission location and air shift would mean one less lever in the car that could get screwed with because I'm going to have two other levers in the cab for the fire suppression system and the parachutes, probably not necessary on this car but I feel better about having them and not needing them as opposed to burning the car down because something went wrong on the road
 

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So you want are shifters but manual parachutes? It sounds like you have your mind made up on what you want to do so good luck with it and let us know how it turns out.
 

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CS1 is obsolete so forget that.
CS2 from memory is 250 psi to the pods or get manual levers and drive it. If your on the street mostly then it would be the way to go.
Next is, running a Lenco on the street is not the best choice as it has no real oiling system and they wear quickly as that was not their intended place.
At 2600 hp, you may want to think twice about a 4l80e.

Maybe consider a T400.


Hutch
What wears out driving the lenco on the street? Clutches/bearings?
 
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