Posted on 02/09/2015 6:05:02 AM PST by rickmichaels
I don't know if they do. Powerglides are pretty popular. Some of them have air-shifters which don't use a clutch. It depends on what kind of drag car it is.
I don’t think there are many “Turbos” on the drag racing circuit.
Oh sure there are. Happens all the time. Usually twin turbos.
I’d venture to say 70% plus of drag cars are NOT shifted manually.
Lots of HD Powerglides as you pointed out, and the pro classes have air shifted specialty transmissions.
As a guy who designed automatics for 25 years, I can say we rejoiced the day the engine guys let us into that software system that controlled the engine and we implemented "torque management".
I’d venture to say 70% plus of drag cars are NOT shifted manually.
Are you really sure of that ?
No matter what RPMS the motor can produce, the lag between “increasing RPMS” and the inevitable “MAX RPMS” and the vacuum needed to signal a shift “automatically” is lost power.
I would venture to say that Drag racers are manually shifting in order to maintain an “increasing” RPM engine output.
I hang out at Lucas Oil Raceway all summer long here in Indy .
That’s where they run the biggest race in drag racing, the US Nationals.
I hang out at Lucas Oil Raceway all summer long here in Indy .
That’s where they run the biggest race in drag racing, the US Nationals.
I missed my calling.
I’m a bit old school, but I do know how things work.
I’ll stand with my belief that an “Automatic transmission” is faster than a manual.
They can be programmed to shift at a predetermined RPM. Most of those engines are dyno tested repeatedly and their torque curves mapped and analyzed constantly.
The engine in a drag car only runs full throttle for a few seconds, the accuracy and timing of the shift points is critical for a winning run...lots of things are.
Barometric pressure, air temp, relative humidity, tire pressure, track temp, wind direction, fuel characteristics, what the driver had for breakfast...
“Boost” engines don’t have usable vacuum.
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My supercharged Mercedes has vacuum assisted brakes , supercharged engines do have vacuum at part throttle. A large accumulator/booster is usually sufficient for anything short of actual racing.
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