500 rwhp on a Mustang dyno with my ProCharger D-1SC setup through a T-56.. The car trapped 120-124.

With 640-650ish on a DynoJet through a 4L60 on my turbo combo the car traps around 139 MPH.

 

Silver95 started to explain it and I will further the thought. The torque converter acts as a torque mulitplier... Using mechanical advantage and slip to let the engine sit at peak torque for the entire launch. A dedicated dragstrip auto will actually drop below the stall speed during a shift. I was shocked to find this out but my boss/buddy has a V6 Camaro auto clickin' mid 9's N/a. Held the record and is about to take it back. He has a 7000 stall and shifts is PG at 9k. This would normally let the engine lug to 5500-6000 but the stall lets the engine spin at max power makin' it quicker down the track. BUT.... that's only for a dedicated drag car. A street/strip just helps at the launch and the converter is out of play for the rest of the trip. This explains the great launch and great times with the lower ET. The M6 has less mass to move around so it doesn't rob as much power. If you were to swap transmissions ON THE DYNO... they M6 will show around 10% more power on the same engine. They don't rob you going down the track. This explains the higher HP and higher Trap speeds with the same ETs as the autos. And one more point, I don't care HOW FAST you think you are... when you go to snap that next gear in your M6 you are NOT ACCELERATING for that .2 secs... and the auto is... it never stops pulling. So suppose you could pull a .15 gear shift.... X 3 shifts down the track... = .45 secs of not accellerating. Doesn't seem like alot but it makes a difference. That would be like the auto rocking off the gas and coasting for .5 secs around the 1/8 mile marker. So that's why the M6's have to post a higher trap to make the same ET. If you want the fastest toy at the track, go A3 with a stall speed right at or over your peak torque RPM, if ya wanna have more fun grab a M6 and bang some GEARS!!! I've got both... my A4 is faster... but my M6 is alot more fun!!!

 

Tech Talk



Stall Torque Ratio is one of the most misunderstood aspects of torque converter construction. Our competitors often call stall torque ratio: torque multiplier. The stall torque ratio is the amount of engine torque that the torque converter can multiply at a particular rpm level. By definition, stall torque ratio is when the turbine is at 0 RPMs and the converter is at maximum designed stall. This will produce a positive push on the turbine to increase the torque to the input shaft of the transmission, multiplied by the designed stall torque ratio of the torque converter. For example, a stall torque ratio of 2.0 would multiply 200 lb. ft. of engine torque to 400 lb. ft. of torque at the transmission input-shaft.

The misconception of stall torque ratio is that more must be better. This is not always the case. High stall torque ratio applications, typically are for industrial equipment or engines with limited low rpm engine torque. With high stall toque ratio converters, there are important trade-offs. What you take at one end you give up on the other. Typically, a torque converter with a very high stall torque ratio, such as 2.0-2.5, will be much less efficient above its rated stall speed. There is a sacrifice in higher rpm efficiency to achieve high stall torque ratios. That lower efficiency translates into less horsepower transmitted to the tires over an RPM range.

The problem with a high stall torque ratio converter is that it is only high while the car is not moving. Maximum stall torque ratio occurs at wide open throttle with no rotation of the transmission input shaft. As the input shaft starts to rotate with vehicle forward movement, the stall torque ratio will become non-existent much sooner than a converter of the same stall, with a lower stall torque ratio. A converter with a stall torque ratio of 2.2 for example, would display that at the starting line, but it would drop off much sooner than a converter with a lower stall torque ratio.



For example: A competitor's converter with a claimed stall torque ratio of 2.5 would typically have an efficiency of around 90% at high RPMs (5,000 plus). That means 300 flywheel horsepower would translate to 270 horsepower at the transmission input-shaft. A Super Yank Converter with a stall torque ratio of 1.6 has efficiency in the 97% range. That means a 300 horsepower engine would transmit 291 horsepower to the transmission input-shaft: A gain of 21 horsepower!

As you can see, the converter with the lower stall torque ratio will multiply torque for a longer period of time than the converter with a higher stall torque ratio. As most of you know, most racing occurs above 3,000 RPMs. That's why the lower stall torque ratio often wins the race:

*Lower stall torque ratio is gentler on the tires at the initial launch, but it will pull harder for the remaining 1,305 ft. of the 1/4 mile. Less races will be lost at the starting line from excessive wheelspin.
Lower stall torque ratio will be more efficient and transmit more torque and horsepower to the tires. This translates into lower ETs and higher trap speeds!

 

Well the run that was 10.5 at 142 was about 11psi so i would say 740-750hp.

1.8 60 ft
142 mph
10.5
M6

3990 with driver..

Car did a 1/4 burnout then snapped the k member. Havent bothered since

 

Whats really interesting to me is some people with a little of 600 are running in the 9's

 

I ran 9.90s @ 136 with 550rwhp(dynojet) @ 3300lbs

 

While my car is heavy, it is setup for drag racing (shocks, control arms, QTPs, etc etc)

618rwhp (SAE) 760rwtq
Dynojet
4125lbs (weighed on scale, full tank & driver incl - i.e. racing trim)
10.42
131.4

It does 60' well (1.4x on 5 passes that day). And I documented on this dyno an additional 7% loss from the 9" & stall. Also, my impeller was dinged up so when I get it back next month I should have 15+ psi & HOPE to run a 9.9x this year. But only once.

Interesting subject. Hope that helps your investigation John.....

 

What a heavy pig! But good times

 

What is it with WS6 cars being enormously heavy? My LT1 WS6 car is about in that range and no one seems to believe it when I tell them…