Forcing an *up*shift in an automatic--mpgs

and the irony is that MY race car has an automatic - the rules require it (stock car)... yet the car originally was a stick.

If you own a sprint car, how much to let me try it? :)

Ray

Reply to
Ray
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Sounds like what you want is something like the Porsche Tiptronic transmission. Other manufacturers have their own versions of this.

With electronically controlled transmissions, its just a matter of the processor commanding the shifts based on user inputs rather than preprogrammed shift points.

If you could figure out which solenoids are opened and closed for each shift, you could probably put together some simple logic to step through the shifts based on driver inputs.

You could easily screw something up by mis-shifting. But stick and clutch drivers have had that ability for years. The factory units (Tiptronic and others) incorporate the best of both worlds. You can shift pretty much as you want, but there is still some logic in the loop to prevent really stupid (and expensive) mistakes. Automatic tranny repairs tend to be much more expensive than stick and clutch repairs.

I've seen after market engine controllers. I've also seen home-brewed ECMs build by people with extensive automotive and electronics experience. I would think that there would be after market transmission controllers available, particularly for 'sportier' cars (forget about the minivan) which would include manual override functions.

There are other reasons to tinker with stock shift points. My Landcruiser has a feature for skipping first gear when starting off on slippery surfaces.

Reply to
Paul Hovnanian P.E.

That has nothing to do with the shift settings possible for an automatic. If there was a thread about trying to make the clutch work smoother on a manual transmission would you say "the solution has been around for a while. We call it an AUTOMATIC transmission."

Reply to
Ashton Crusher

True- but hybrids now have regenerative braking. Plus you don't have to drop the transmission to put on new brake pads....

It's not like

Only on break-away from a stop, assuming the driver is competent at operating the clutch... :-/

Reply to
Steve

Sticks in racing: Formula 1- no IRL- no CART - no NASCAR - yes Rally/hillclimb/etc. - yes

Conventional manual transmissions are in the minority even in racing these days.

Reply to
Steve

fine. The solution to your problem has been around for a while. It's called a replacement valve body for your transmission.

Frankly, on the cars I've owned, the automatic transmissions do a pretty darn good job of knowing when to shift up and down in regular street driving.

Ray

Reply to
ray

IMO: Clutch = manual transmission, Torque Converter=Automatic.

from wikipedia: "Formula One cars use semi-automatic sequential gearboxes with six or seven forward gears and one reverse gear. The driver initiates gear changes using paddles mounted on the back of the steering wheel and electro-hydraulics perform the actual change as well as throttle control. Clutch control is also performed electro-hydraulically except from and to a standstill when the driver must operate the clutch using a lever mounted on the back of the steering wheel. By regulation the cars use rear wheel drive. A modern F1 clutch is a multi-plate carbon design with a diameter of less than four inches (100 mm), weighing less than

2.20 lbs (1 kg) and handling 900 hp (670 kW) or so."

from my reading, an IRL or CART car uses a similar type of sequential style gearbox, but it's still got a clutch.

How many automatics will you find in Stock Car road racing - SCCA type of stuff?

24 Hours of LeMans? 24 Hours of Daytona?

I think that conventional automatics are the minority. Entry level dirt track and bracket drag racing are about the only places you'll see a torque converter.

Ray

Reply to
ray

That's one way to look at it... but on the other hand an electric paddle switch that tells a gearbox to shift up or down a gear without use of the clutch is hardly a "manual" transmission in the conventional sense, and that's exactly what F1, IRL, and CART cars use. At best, its a "manumatic."

What I said. ;-)

Reply to
Steve

The paddle shifter also controls the clutch in an F1 car.

What do you consider a motorbike gearbox then? It's a sequential shift.

Ray

Reply to
ray

Not on a vehicle with electronic computer control of the transmission. The valve body modifications will only change firmness of the shifts.

Don

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Reply to
Don

Actually, the diesel drives a generator which powers traction motors directly--at least on smaller work-type locomotives, and I'm pretty sure on the big boys as well. The rpm does seem to vary from idel to load, like gas-powered welders. In NYC subways (all electric), regenerative braking far exceeds the friction brakes, ito power. Unfortunately, this regenerative power is bled off through huge resistor banks, and not fed back into batteries (there are none), and not back into the third rail/running rails, because being unregulated it interferes with the trackside signal systems.

The Prius has battery-charging regenerative brakes, fwiu.

But, pure battery operated vehicles w/ an ancillary generator would seem simple and workable, mebbe w/ some solar roof chargers. Something perhaps a diy-er could do. Yeah, detroit would love dat.

Reply to
Proctologically Violated©®

Indeed, MOST Diesels drive the motors directly. However, there are now some hybrid locomotives, designed for yard work where the power cycle is very peaky. These do have batteries, and a smaller engine (or two).

Reply to
Don Stauffer in Minnesota

Yes, even the 6000-horsepower GEs work that way (the biggest locomotive currently built).

Not much. Idle on a locomotive diesel is around 400-500 RPM. WFO pumping out all 6000 horses is 900 RPM.

Reply to
Steve

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