GM 4-Speed Manual

GM Manual Transmissions

Muncie M21/M22 (Also M20 and BW T-10)

Lawrence Wight's, 69 Camaro

Gear Vendors owes a lot to the Muncie close ratio trans. These words are very similar for the M20 and T10 but with some slight ratio differences depending on model.All M21/22 have the same 22% upshift and 28% downshift spread as the Gear Vendors.

Overdrive is the first reason you are going to add the Gear Vendors. 28.6% faster cruising speeds than you have now. Your 4.10 gears will cruise like 3.20s and your 3.55 will cruise like 2.77s. If you are normally aspirated expect 28% better fuel economy. If you have forced induction expect 50% better mpg.

M21 Kit

Performance is what the Gear Vendors is all about. This product is a very high-tech planetary overdrive. With our Auto-Launch circuit on you will leave the line in 1st and as the engine gains revs it will automatically shift clutchless to 1st-overdrive. This means you are 28% farther down the track or street before you have to clutch the car. This is key to acceleration as otherwise any manual trans car gives up big hunks of time to an automatic on the 1-2shift. Gear Vendors 1st-over ratio is only 7 hundredths different than having shifted to 2nd (not discernable and actually closer in ratio).

M21 Electrocnis

It is not just 1st-over where you can use this clutchless shift. You can be in 2nd just boulevard cruising and show off by stepping on the throttle and hitting the Gear Vendors button on your sifter for 2nd-over which is identical (exact same ratio) as having shifted to 3rd but only clutchless (and with a nice bark of the tires). Most street guys will just grab a clutchless gear at whatever moment they start accelerating and then progress up through the gear box leaving the overdrive on so that each gear is just now up a step.

The bracket racers and serious street guys will flip the 3-4 side cover lever over so they can easily have two clutchless shifts in the ¼ mile with just one clutch depression. Flipping the 3-4 cover lever over lets them grab with a straight pull back because it moves 3rd to the 4th gear position on the pattern. Just awesome performance gains greater than a full second on the watch, increased mph and far more performance than any 5spd or 6spd tranny swap.

M21 Kit Rear View

So you get a 5th gear overdrive and at least one clutchless shiftto be used at any moment (we ship the kit with our 6speed car badges) and a huge performance gain plus get to retain your period correct transmission in the car and get the worlds strongest overdrive trans. Since your Muncie or BorgWarner is stronger than any non-race 5 or 6 speed, the Gear Vendors is just he right way to get overdrive in your GM manual performance car.

The Gear Vendors comes with a 30 day money back guarantee so you know you will be happy with everything you get from us and how it installs and drives.All our kits also have our 2year unlimited mileage, horsepower, and abuse warranty – you can go to the dragstrip every weekend and still be covered – no other overdrive can handle that.

For more details on this subject click here.


Gears Under/Overdrive

It is the gear under your seat that counts. Gearing is what you are buying when you purchase a Gear Vendors Under/Overdrive. If you take a few moments to study the gear chart for your transmission and rear end ratio combination you will see why this product is so popular. The Final Drive Ratio shows you how many times the engine turns for one complete turn of the tires. Gears are multiplier of torque. The mathematical equation for Horsepower is; Torque X RPM/5252 = HP. Close ratio gearing lets us work both the torque and rpm side of this equation for big gains in HP and performance.


M21/22 4-SPEED Close Ratio – showing clutchless options
 Axle Ratio4.884.564.103.733.553.42
 Trans RatioFinal Drive Ratio
M20 4-SPEED Wide Ratio – showing clutchless options
 Axle Ratio4.103.733.423.313.08
 Trans RatioFinal Drive Ratio

CHEVROLET / GMC Application Guide 2-Wheel Drive Manuals

 ApplicationPrice Code

Price : $3,295.00

Price : $3,295.00

Price : $3,295.00

Price : $3,295.00

Price : $3,295.00

Price : $3,295.00

Price : $3,195.00

Price : $3,195.00

Price : $3,295.00