CS4 3 Speed

CS4 3 Speed

Lenco CS4 Transmissions

For more specific information on any of these Lenco transmissions please refer to the Tabs below, or call our tech line at (909) 673-9080. Lenco Parts and Price List is available here.

The Lenco Racing CS4 3 Speed Transmission is the smallest and lightest version of our New Generation designs. The very compact CS4 is engineered for cars producing up to 1800HP and weighing up to 2700 pounds. Standard planetary gear size is 5/8 ". The CS4 is ideal for IHRA Pro Stock as well as NHRA Competition Eliminator machines.

The New Generation CS4 LENCO is available with up 5 forward speeds plus reverse. All shafts are available in Marage or 300M material. We offer a variety of procedures for lightening rotating mass - such as optional titanium planet cases - and suggest you call to discuss your specific application and objectives. A Low-Drag reverse is also an option to our standard reverse unit.

As with all LENCO transmissions the CS4 may be shifted with CO2 or manually by our patented lever system. A lightweight billet aluminum case is standard.

CS4 3 Speed
Two billet aluminum cases. Handles up to 1800 HP. Designed for lighter weight Top Sportsman, cars and big HP boats. Smallest sized LENCO fits the most cramped quarters.   Air or lever shift.

Reverse Unit – available Option. However, if bought separately, price is $2,050.00
Billet aluminum case. Mates to CS1, CS2, CS3 or CS4 transmission. 5 1/2" long, manual shift only.


Available also in:

CS4 2 Speed
One billet aluminum case. Handles up to 1800 HP. Made for lightweight sand-drag cars, river boats, pullers, mud boggers and nitrous oxide assisted machines. Engineered for application in restricted space. Air or lever shift.

CS4 4 Speed
Three billet aluminum cases. Handles up to 1800 HP. Recommended for light weight nitrous oxide or supercharged machines where four speeds are necessary.  Perfect for Top Sportsman and Compact/Import classes requiring extensive gearing choices. Air or lever shift.

CS4 5 Speed
Four billet aluminum cases. Handles up to 1800HP. Recommended for lighter weight Pro Stock, Comp eliminator and Compact/Import classes. Up to five forward speeds plus reverse. Wide variety of gear ratios allows the opportunity to employ narrow rpm range. Air or lever shift.

5/8" Gear Set.
Light weight components.
Light weight ring gears (units w/27 and 32 spline shafts only.
Low drag (angular contact and needle bearings.
Choice of ratio.
New generation reverse w/neutral.
Air servos or max-adjust shift towers.
Input shaft.
Throwout bearing collar (4 & 5 speed only).
Choice of shifter style and lockout style.

CS4 Gears 5/8"

1.16% Uses 21/36 tooth planet gears, a 22 tooth sun gear and a 79 tooth ring gear.
1.19% Uses 21/33 tooth planet gears, a 22 tooth sun gear and a 76 tooth ring gear.
1.20% Uses 22/32 tooth planet gears, a 22 tooth sun gear and a 76 tooth ring gear.
1.21% Uses 21/31 tooth planet gears, a 24 tooth sun gear and a 76 tooth ring gear.
1.22% Uses 21/30 tooth planet gears, a 24 tooth sun gear and a 75 tooth ring gear.
1.23% Uses 21/30 tooth planet gears, a 25 tooth sun gear and a 76 tooth ring gear.
1.24% Uses 26/31 tooth planet gears, a 23 tooth sun gear and an 80 tooth ring gear.
1.256% Uses 32 tooth planet gears, a 22 tooth sun gear and a 86 tooth ring gear.
1.280% Uses 27 tooth planet gears, a 21 tooth sun gear and a 75 tooth ring gear.
1.297% Uses 26 tooth planet gears, a 22 tooth sun gear and a 74 tooth ring gear.
1.313% Uses 27 tooth planet gears, a 25 tooth sun gear and an 80 tooth ring gear.
1.338% Uses 24 tooth planet gears, a 25 tooth sun gear and a 74 tooth ring gear.
1.356% Uses 23 tooth planet gears, a 26 tooth sun gear and a 73 tooth ring gear.
1.368% Uses 21 tooth planet gears, a 25 tooth sun gear and an 74 tooth ring gear.
1.378% Uses 23 tooth planet gears, a 28 tooth sun gear and a 74 tooth ring gear.
1.405% Uses 23 tooth planet gears, a 32 tooth sun gear and an 79 tooth ring gear.
1.438% Uses 20 tooth planet gears, a 32 tooth sun gear and a 73 tooth ring gear.
1.479% Uses 19 tooth planet gears, a 35 tooth sun gear and an 73 tooth ring gear.
1.500% Uses 19 tooth planet gears, a 38 tooth sun gear and a 76 tooth ring gear.
1.566% Uses 18 tooth planet gears, a 45 tooth sun gear and an 81 tooth ring gear.

In general, all LENCO transmissions are a planetary design. Planetary transmissions rely on a central sun gear to provide a 1:1 direct drive ratio once shifted from the launch ratio.


In order to achieve an underdrive first gear launch ratio the LENCO transmission relys on planet gears which rotate around the sun gear.
 

Each sun and planet gearset provides two speeds. Those two speeds are (1) the lower underdrive ratio and (2) the direct 1:1 final lock-up drive ratio.

 

Each LENCO transmission is thus a two speed and is housed in one dedicated two speed.

We acheive more than two speeds by combining multiple cases.

For example, a three speed requires two cases.
A four speed requires three cases.

A five speed requires four cases, and a six speed requires five cases.

 

 

Since each case contains one gearset and provides both underdrive and direct drive, multiple cases (gearsets) provide multiple underdrive ratios.

 

You must multiply each cases underdrive ratio in order to determine the first gear ratio.


In the example of a four speed, the case nearest the engine would contain a 1.37 ratio planet gear set. The middle case would also contain a 1.37 planet gear set.
The rear case a 1.31 ratio gearset.

 

 

By multiplying these three ratios you come up with a 2.46 first gear ratio. Second gear ratio is 1.80 and third gear is a 1.31 ratio. Final drive ratio is 1:1.

 

Multiply all three gearset ratios to determine the first gear ratio of 2.46:1. Multiply the two rear case gearset ratios to determine the second gear ratio of 1.80:1. The gearset in the third case alone, 1.31:1, determines the third gear ratio. All three units shifted equal final drive ratio of 1:1.

 

The internal action of a LENCO is such that when the transmission is in first gear the dedicated planet gear assembly provides the launch ratio. The planet gears are driven by an encompassing ring gear.

 

When the transmission is shifted a clutch pack compresses the rotating sun gear assembly to the direct drive central sun gear. Thus a 1:1 ratio is achieved.

 

Each case in succession, with its particular underdrive ratio, determines the immediate drive ratio.

 

Once all cases have been shifted the entire transmission assembly is locked in the final 1:1 direct drive ratio.

 

It is not necessary for the driver to disengage the clutch when shifting from ratio to ratio since all shifting is done with the engines clutch fully engaged.

(909) 673-9080

Please call for ordering or technical information.

  • Views: 42360
  • Brand: Lenco Racing
  • Product Code: CS4-3
  • Availability: In Stock

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Tags: cs4, transmission, racing transmission, 3 speed

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