Custom Transaxles

RAT Transaxles

"You don't need no stink'in 5 speed!!! You have MassIVe power now, and plenty of torque for a monster 4 speed to do the job as well as a 5!!

All our transaxle combinations are configured for Type IV applications and are a result of testing with our own conversion engines. We offer complete Transaxles for sale as individual items or drivetrain packages for any aircooled VW or Porsche that has been converted to MassIVe power with one of our Type IV engines.

The Type IV engine makes a TREMENDOUS amount of torque in comparison to any stock Type I. A stock Type I transaxle will hold a lot of power, but due to its configuration as it was originally designed it does not compliment a Type IV engine. The Type IV makes more torque just off idle than a stock 1600 did at peak torque! VW designed the stock transaxle to allow for lower loads to be placed on the engine by using lower gears to keep the engine in its powerband, and the cooling fan turning to cool the heads. High gears need more torque and better cooling capability to be successful. Note that I said better cooling "Capability" and not a "Better cooling system" there is a big difference in these two. With a Type IV installed in your Type I you can throw away the factory designed gear ratios and now run higher gears more along the lines of the Porsche 901 transaxle. Optimizing the gearing for your engine is one of the biggest mistakes made by convertees of Type IV engines. While you can install the Type IV with your stock gearing, you'll save more in gas in a few thousand miles than my transaxle will cost you. You will gain the advantages of better usable power, lower engine oil temps (less RPMS at higher speeds) and be able to cruise at 90 MPH all day long on the freeway- Just like a Porsche!

We electronically configure your engine, and transaxle and even the cooling system to work as ONE UNIT, like the factory would do it! We don't just grab a box of gear stacks and install them with a "3.88 Ring and Pinion" and let it go at that like most all the "Freeway Flyers" that grace the magazine ads. Just as smooth as a "well oiled machine" is the way we would best describe a complete, well thought out and designed transaxle. To do this we need the size of your rear tires measured in inches, some information about the type of driving style you have, so we can create a package that will use your engines volumetric efficiency best. This yields a package that has a wide, usable power range, good fuel economy, and lower operating temperatures.

All our transaxles come completely ready for a Type IV engine to be bolted directly to them with stock parts. We use a few particular transaxle cases that are more friendly from the factory with the Type IV engine. While all 1962 and later Type I transaxles are Type IV compatible 100%, there are a few years and series of cases that have better characteristics for the Type IV.

We have basically 3 stages of "tune" for your transaxle. All of them have different gear ratios, and the stages basically represent the strength of the transaxle, and not the gear ratios.

"A" Transaxle

Available in Swing and IRS versions, this transaxle was developed for our 1700cc through 2056cc engines. This transaxle is ideal for a 2056 engine, with mild modifications. It has stock gearing in the first and second ranges, a slightly taller third gear, and a proven, genuine VW overdriven fourth gear. To better handle the increased torque of the Type 4, third and fourth gears are welded. The "A" transaxle benefits from our custom gear ratios, but does NOT have a "Superdiff" or welded side covers. The bell housing is compatible with any Type IV engine conversion.

With carefully thought out gear ratios, this transaxle will allow great acceleration and mid range power, while giving a great cruising capability on the open road for your smaller conversion engine. This transaxle is rated for engines making less than 130 lb/ft of torque. It is not designed for spirited drag race type starts, or jheavy clutch drops, or burnouts. If you want to do those, look into the transaxles that we have designed to live through this type of abuse.

Our "A" transaxle is designed to use a 25-26" tall tire for correct final drive, that optimizes the torque of the smaller displacement Type IV engines (to 2056cc). We have chosen to refrain from posting actual gear ratios of any of our gearbox combinations; they are available after the customer has initiated an order with us with a deposit. Choose one of our engines to go along with this gearbox, and the open road has never been better!

"A" Transaxle is available for $850.00 with NO core charge, all transaxle sales are outright. Remember that all transaxles are sold more economically when purchased with an engine. This transaxle is NOT available as a 5 speed conversion.

"B" Transaxle

Available in Swing Axle and IRS versions, the "B" gearbox is our medium duty transaxle, designed to hold moderate torque from larger displacement Type IV engines as well as for those with a heavier lead foot. This gearbox is always a custom build and incorporates everything from the "A" gearbox, and a lot more including the "Superdiff" , heavy duty side cover and welded gears. Custom gear ratios and cryogenic enhancement options are commonly purchased options. Configured as we typically ship them, the "B" Transaxle runs less than $1300 and are compatible with any Type IV conversion.

This is the most widely purchased transaxle we sell and is best suited for engines with at least 130 lb/ft of torque and 125HP but not exceeding 170 lb/ft of torque or 165 BHP. These transaxles are mostly used by our customers with one of our 2270cc series engines, that like to drive more spirited. The gearbox is strong enough to take drag race type starts as long as the rest of the suspension is up to par, and wheel hop is controlled. It will take gear slamming and burnouts if done with common sense and by utilizing the preload method before attempting such activities.

This transaxle coupled with a 2270cc MassIVe Type IV is the most well researched, and most highly developed combination that we offer- BY FAR!

The "B" Transaxle is available for $1250.00 with NO core charge, all transaxle sales are outright. Remember that all transaxles are sold more economically sold when purchased with an engine. This transaxle is NOT available as a 5 speed conversion

"C" Transaxle

This is the biggest of "Big Daddy's"... And available as a 4 speed or 5 speed!

This series of transaxles are for those who have the larger wallet and have purchased one of our "MassIVe Superhero" engines. This transaxle has an aftermarket mainshaft with custom gears to allow for higher gear ratios that the "Superhero" engines produce. This transaxle is built from the strongest core transaxle cases and aftermarket cases are available if you are running excessive torque and high HP.

The "C" series transaxle has the capability of holding well over 200 lb/ft of torque, as almost all our "Superhero" engines produce at least this amount of power on our dyno. The transaxle has the best of components inside it, and has the option of a Quaife Torque biasing limited slip differential. This transaxle includes full cryogenic enhancement of all gears and sliders and shafts.

This transaxle will take very hard driving, burnouts, clutch drops, and as long as you have traction and no wheel hop- you might just get the front wheels in the air with a "Superhero" powering your car! If you want to see me really abusing a "C" version gearbox in my personal car, watch the video of a 2332 TI making 227 BHP revving to 9,000 RPM and doing a 4th gear burnout going through the gears... I tried to explode this gearbox, but its still together and in my Blue beetle still today!

The price of the base "C" transaxle is 1599.00, and includes no options except Cryogenic enhancement of the internals. Prices vastly according to the specifications of the engine we are building for you. This transaxle IS NOT sold as an individual unit, like the "A" and "B" transaxles are.

If you desire this gearbox in a 5 speed configuration, it will not be cheap. The price of this top of the line transaxle with all race duty internals and a 5 speed kit and the necessary mounts and shifter is 3,950.00 without the Quaife LSD.

Huge engines require huge budgets and great gears to get the power to the ground, if you can't play with the big boys, get a higher credit limit!!! Then call me.

Jake Raby
"Excellence in Research"