But, I like to shift.... Automatics eat up horsepower... Only use 3 gears? My engine builder says I need a 5 speed!... How much horsepower will it handle?...Can I lean on it in reverse?... Won’t they always overheat? These and many other similar statements are heard on a daily basis at our shop. And, we are the first to admit the Field’s 3 Speed Automatic should be just one more option to consider for an off-road/sand car application. At Transaxle Engineering, we strive to suggest the correct combination for each cars setup. One of the many reasons we service and sell every transaxle on the market.

Automatics cannot “eat” horsepower. Horsepower is lost in all vehicles. The amount lost depends on many different variables such as: vehicle weight, suspension dynamics, tire size & type, clutch/torque converter style/condition, engine torque @ what rpm, desired top speed vs. frontal area, geartrain type/toothform & design, and lubricant… all have to factor into the equation. How much horsepower? The reality is, it’s the drivers good/bad habits that really determine the HP number for a given drive train. The Field’s 3 Speed Auto is in many twin turbo/blower sand cars with 1000 HP+ on honest engine dynos and even more 600 HP / 4000lb prerunners going thousands of miles between service intervals. Let’s face it; any transaxle for that matter can be grenaded in a matter of minutes if the driver is abusive. We all know people who destroy parts regularly, that’s why we don’t let them drive our cars!

If anything is “slipping” within the Automatic it is creating heat and that is what the torque converter does below its designed stall speed/rpm. For example, if you’re cruising the dunes @ 3000 rpm-part throttle… no problem, but when you are hard on the gas at 3000 rpm in 3rd you are definitely making converter heat because the torque converter is below its designed stall RPM. You’re better off shifting back to 2nd gear to get the car back on top of the sand and click 3rd again. Heat is not created within the automatic from slippage since the manual valve body allows us to direct full oil pressure to the clutches & band selecting what gear you want. When you you’re shifting the automatic you won’t hear clunks or grinding noises, since it is a band or clutch pack being applied hydraulically. The Field’s 3 Speed Auto is unique in that 100% of the main oil flowing out of the converter is plumbed directly to the heat exchanger/cooler before returning to the transmission pan. Because of this, properly plumbed cars and good drivers don’t have heat issues. An optional electric boost pump feeding an additional air/oil fan equipped cooler is available for super heavy vehicle high HP cars that want to see still lower temperatures.

Got stuck? Been there, done that. Put it in “R” and rock & roll. The same planetaries and clutches that give you low gear also provide the ease of backing up and on the gas if need be. In addition, backing the car into the trailer is hassle free. The dreaded reverse gear is no longer an issue!

And lastly, why only 3 gears? For our application, with the broad torque curves provided by available V6/V8+ powerplants, and the torque converters ability to “fill” the space between ratios, it is all that is needed and in actual use, all we use is 2nd and 3rd. The hundreds of final drive ratios are possible thanks to our “quickchange” style gear sets, which allow us to keep final drive ratios low. When the car is shifted into 3rd gear the clutches lock the shafts together with all of the gears spinning in oil, but doing no work. Also, one of the main bonuses is the converter acts like a shock absorber between the engine and the tire. Ring & pinion, axles, cv’s, differential…these and many other parts are cushioned from shock loading by the fluid coupling. In theory you could say that the torque converter is doing most or all of the work and soaking up a good amount of the shockload imposed by the tire/motor. Most of our Fortin race customers who have given up a clutch have at least doubled their ring & pinion mileage with a converter. 1st thru 4th gear sets in those transaxles also pass Magnaflux & live longer as well.

Weddle Industries now offers converter options for the Albin’s transaxle line, and Mendeola has prototypes running on the S4/HD units, all for this reason. We’ve been helping customers install torque converter equipped transaxles in off road/sand cars for 15 years, and thankfully are still being educated by it and learning how to do it better…. And it’s still fun! If on the other hand if you’re the type that enjoys short stroke, high RPM screamers making their impressive horsepower numbers up top in a small range, our computer is ready to help determine the ideal gear ratio setup for your bus box, Mendeola 2D, the new Weddle HV-1, or any other unit you may be thinking of.

Everybody’s needs and wants are different and anyone who says a combination is the only one for that motor - or that car and tire, may not fully understand your needs. If you run a lot at say Sand Mountain or Little Sahara at altitude and can lose HP accordingly. Most importantly, gather input from many sources, so you can have an optimized combination that works for you! We hope this helps and of course, feel free to call any time…. Ask for Jeff!

See you in the dunes.

Transaxle Engineering

(818) 998-2739

Chatsworth, CA

Transaxleengineering.com

Great info! Thanks

How much for something to hook up to a 200-250hp Subaru Motor??

these babies are bombproof!!! I would love to own one!

Good read. Welcome to the boards

Please post some tasty pics of your products and the rides they live in. We're a visual group, much like kindergartners- we read pictures very well.

Here is their 3speed bus auto. It lives in my burnt up baja. It will be in my next 4 seat build as well!


And the ride it was in...

I'm sold on convertors....in my 1100 h/p car I use to go thru clutches every other trip now I have 17 trips with a Fortin and haven't had an issue the t/q has two air to oil coolers and never gets above 250 degrees ....My new 1500 h/p also going to have a T/q but with a sesq Albins....builders choice of tranny.

Wow thats the info that will be needed for many of the baller's. But is this a Baller only Trans or is it available for us broke guys as well???

id love to use the diff part in my build hooked to my powerglide.

pm sent also take a look at neptrics pictures that is the bus automatic.

[quote name='Kevin' date='Oct 12 2009, 12:49 PM' post='3474947']
id love to use the diff part in my build hooked to my powerglide.
[/quote hows the car looking/ coming along kevin,any new pictures?

We offer a bus automatic for the cars up to 350 H.P. 3 SPEEDS,manual valvebody ,930 cvs only avalible in rear engine ap.and in a 4.10 final drive ratio. with all the goodies for $5500

its coming along slowly. nothing new lately. gotta draw up some stuff to have lasercut to mount the rear diff, some other small brackets for stuff. then just plumb it and wire it. only things i may need to get still are custom axles, not sure if the ones i got from you are gonna work yet.

Here are a couple of pictures from dumont /thanksgiving last year. Valet parking 4 buggys at wiskey petes was the best!

Just imagine what the valets said when you guys pulled in......



and what they did with the cars after you walked away!!!!!!!

My car is the last one in the line, what a blast that was!!
I think we got the most looks from the security in the hotel as we walked to the buffet carrying steering wheels!!!

I can't wait for this year to do it again!

what is the cost for a 3 speed that will handle a 4000lbs car with 650hp v8?

$15500 Thats including the tq. converter. extra is the shifter(winters is what we use) $250 adapter/with flex plate $550 +cooler ,heat exchanger.

will an s4 benefit from a converter ?? can i increase my hp over what i could use on a clutch ??? how would the dog legs wear with a converter??? what would a converter conversion cost ?? and lastly how do you cool the the converter on this set up ?? does it mount up with a pump like an auto and run through a cooler ??

bob, find supreme airs fortin converter thread, im sure ut wouod be pretty much the same as a conversion for a fortin.

gotcha they started to do one at eyeball then the customer changed his mind and went with a clutch. next year i would like to pump up the ponies but im already on the ragged edge with my s4. maybe a tourqe converter could change this up a bit

products

Here are a couple of my car with the new body and paint !!

naa my s4 is 5 years old. i have never blown it up and ive ran big hp through it. ive been through 3 motors

Considering all the trans issues lately I figured I would bump this to the top. Great guys, great products and great service!

What was the problem with the tranny on the new Funco for Bill Jones - blew first rip out.

he forgot to down shift ,trying to lug 700 hp in high gear will make a little heat.

Expensive mistake there. Just curious but what type of a price is a rebuild on the auto's? Cheaper/the same/more expensive than the other transaxles out there?

A rebuild on the diff/auto depending on mileage will run in the range of 1500-3000 .

ttt

You forgot one thing. With an "automatic", your never out of gear between shifts. Your always under power.