Supercharger

The "Dragon" torque converter offers better standing start launch and improves acceleration for auto RX-8s.

http://www.converter.com/dragon.htm

http://www.tciauto.com/tech_info/tor..._explained.htm

Supercharger

Dragon Torque Converter Upgrade Features:
- 9.5" diameter
- better torque multiplication than OEM
- A Unique Billet Front Cover
- 4130 CNC Machined Turbine Hub
- Sealed Torrington Bearings
- Furnace Brazed Impeller & Turbine
- Anti-Ballooning Plate
- Reinforced Turbine Vanes
- Heat Treated Precision Hubs
- Electronically Balanced
- Pressure Tested
- Two Year warranty

This is the best and least expensive modification that delivers real world performance increases. It does not affect the driveability of the car.

Stall speed should be matched to engine performance, the car weight, tire size and gear ratio. Proper selection of stall spec will make for quicker launch, better 60 ft. time and better ET. It is very important that these parameters be specified when ordering a converter to assure satisfaction.

norats

Thanks for the post..i've been trying to track info down lately on that.

norats


edit: It looks like 6k max on those? Wonder if anyone can make one to handle 8500-9000? Mazda couldn't do it efficiently, maybe aftermarket will.

wakeech

...it kills me to think that the flunkies who don't make it into the factory can somehow magically invent considerably better units (in all factors) than the big-namers.

there are things you can get which are more performance-biased than OEM, but will either come at the cost of quality, or just dollar amount (in multitudes...). that's fine for some, and the only way to do it, really.

anyhoo, wasn't this tranny the Ford unit?? and isn't Mazda putting together a 5 speed auto, and a 6 speed sequential or something?? Sputnik is always in the details... i'm having a brain-dead afternoon...

norats

Why is that so inconceivable? Maybe people don't want to work for a corporation or do the 9 to 5 thing. If I had the talent to design that stuff (& I surely do not) I wouldn't work for Mazda for a measly 70-80k top end...why? Perhaps in Japan it's for the pride thing.
By the way, I think economics are more of a factor than "ability to design" by most of the performance-based product that's pumped out today.

wakeech

...aftermarket performance part companies are every bit as corporate as non-factory operations, what are you trying to say?? some, yes, go the consultation route, but then they'd not really be considered a part of an aftermarket company... ahhh, whatever. moot point.
basically, factories scoop up all the best talent because they have money, and that's where all the interesting things happen: you won't find any multi-million dollar research budgets at Racing Beat or Pinapple.
besides, what makes you think you're going to end up making more in the aftermarket world of performance design as you would for an OEM??

and yes, economies of scale (based on level of demand) is why aftermarket companies are small, and as such cannot afford to hire the best and brightest, so they settle with the rest: do you honestly think that AEM or even JUN has more brain power behind it than GM or Toyota?? not a chance.

Supercharger

A torque converter is simply a fluid coupler which applies power to the ground through the transmission. An aftermarket 9.5" converter is a smaller diameter and is lighter than factory, therefore has the same effect as installing a lightweight flywheel on a manual transmission by allowing the engine to spin up faster.

The torque converter also acts as a torque multiplier, and by raising the stall speed you can put the engine closer to its range of peak torque. This has the effect of launching the car harder, and once you are closer to the peak torque range, the car will accelerate quicker. Its not uncommon to see reductions of up to 1.5 seconds in the 1/4 mile simply by changing the converter.

It takes about 4 hours for the average mechanic to do the install.
The transmission has to be removed from the car to access the converter.

wakeech

smaller diameter torque converter = speed reduction gearing = more torque??

so, it's like installing a shorter diff: it'll give you better at-the-wheel torque at all rpm, but at the cost of speed at a given rpm in a given gear, fuel efficiency, and other things i'm too tired to think about at 3.42am... hahaha... video games are BAD FOR YOU!!

MikeW

What would be the stall speed of one of those, 4000 4500? considering that peak torque is 5000 rpms
If it were that high, then you can kiss your mileage good bye.


edit
The stall speed would not be high enough for the second port to come online
You can also kiss any sporting driving good bye, you do not get any worthwhile throttle braking below the torque converter stall speed (it is very hard to precisely balance the car below the stall speed)

So the automatic cars should replace their 225/55 16 with 235/50 16 (when the time comes) and then maybe look into changing their axle ratio.

Sputnik

I assume you are trying to say that aftermarket companies are as corporate as major car companies?

Remind me how long have you been holding down a job in the corporate world...

---jps

97gpGT

Toyota has a torque converter in their automatic Celica GT-S that will spin up to at least 8000 rpm without too much of a problem, probably even higher than that. I'm sure that Mazda could do the same, but if their goal is to replace the standard automatic with a SMG version later on, then they really don't have to worry about the torque converter problem, do they? I think they are thinking along these lines...

wakeech

oy, ok. :o

5 months.

i'm not suggesting that the small companies are as large, formalized, regulated and contolled as the big OEMs, but are certainly as business-minded... what norats what saying seemed to suggest that these companies operate with vastly different principals, and are all about performance... romanticizing... they're really just businesses, which although they may come from a romance with motorsport or cars, they do have full time working hours, conduct business just as anyone else does... what i mean is that a job at an aftermarket performance company is not necessarily very different from one in a really big company, and is nearly universally the same.

norats

When you used the word "flunkies", you implied the typical aftermarket business entrepreneur was either fired or simply couldn't get into a big corporate setting, which, of course, is a false ASSumption. Many people do not WANT to be a part of it and are extremly talented at what they do in the private sector, be it automotive or otherwise.
The goal is to put out a better product than mass production can afford to & yes, this will come at a higher per piece cost, since the economy of scale is just not there, but we should expect the quality to be as good or better. It has to or the endeavor won't work. (business(es) will fail)

Man, am I bored...where's my freakin 8!!!

Supercharger

Normal driving is not affected by stall speeds up to approximately 3000 RPM, particularly with a good converter. A car will begin to roll normally when a higher stall speed converter is used. Quick acceleration will be favorably influenced by stall speed. A very high stall speed (above 3000 RPM) would not be satisfactory for street use.

Canada

There seems to be quite a few experts in this thread. That's good, I have a question that maybe you can help me with. I ordered an RX-8 AT GS. It doesn't have limited-slip differential (that was only available for MT) Nor does it have Dynamic Stability Control/Traction Control System (only available for GT). Since the car has these deficiencies, I was wondering whether driving in winter conditions of snow and ice might be difficult. Do you think these features could be added aftermarket, or would the cost be astronomical?


By the way, who can tell me in what year (1975?) was limited-slip differential first introduced into the market?

Supercharger

LSD:

http://www.torsen.com