shurite44, how do you flash the converter on the A6? I hear the turn but not sure what it means or does .

 

What is the difference between "brake stall" and "flash stall"?

3. Flash stall is the maximum your engine's torque can stall a torque converter. In essence flash stall and full stall are nearly identical. If you had a transbrake, you could find full stall by putting your foot to the floor and reading your tach. For argument sake, let's say we're testing a 3500 stall Yank ST 3500. If you had a transbrake, you would see around 3500 rpms. If your motor was at idle and then you suddenly floored the throttle, you might see slightly more (maybe 100 rpm more) stall for a half second as the momentum of the motor's internals "flashed" the converter a small bit above its true stall rating.

Brake stall, on the other hand is a very subjective thing. For most, it's the highest stall you can achieve before your tires spin. This varies greatly based on many factors: Traction, gearing, brake clamping force, and engine torque. With a ST3500, I may only be able to get 2200rpm "brake stall" on the street with street tires...any higher rpm and the motor torque would overwhelm the tires. But if I was at the track with racing slicks on the starting line, I might be able to get 3200 brake stall before the motor torque overwhelmed the tires. See...brake stall is very subjective.

Yank rates their converters based on their intended application. A ST 3500 will stall 3500 rpms in a stock LS1. If you had a 422 and wanted a ST 3500, the converter you received would still stall 3500 because it would be built around the torque of a 422, not a stock displacement LS1. Yank checks the stall of their converters and their competitors by using either a trasmission dyno or a "tranny tricker" in the vehicle tested. With the tranny tricker, you can place the vehicle in 2nd or 3rd gear and stab the throttle to the floor...making it easy to read both flash stall and full stall

http://www.converter.cc/faq/faq.htm

 

No reason to put it in paddle mode. Just put into S and you will launch in first gear.

 

I have found that slighting preloading gives me the best times both ET and 60ft. In fact the only time I have got under 2sec is by preloading. Around 1000-1200rpms. Any higher and the rearend breaks loose.

 

you are correct. I sure hope this pi$$ing match does not start up again.

 

Thanks! Good write up on the previous post! I think I understand. So in a stock C6-A6...you would hold the brake pedal push on the gas just until the wheels start to turn and then let off.....now from idle you just floor it?

 

TMeyers do you have an after market tune? I just wonder why pre loading has not effect on my 60's.

I have a dyno tune but I don't think any TM was removed. Pre loading does make my RT faster when I launch. I sort of use it to fine tune my RT by staging at the same spot and varying RPM's. But my 60's only seem to be effected by weather and or track prep.

 

Purdue to be honest I think people use the term flash the TC for launching in different ways. By the way that was not my definition or write up, I just copy and pasted from that link. I am not that smart.

I always used the term to say I matched my rpm's to the rated stall before I launch. But I have been told that launching from idle is what the term means. So you got me.

I totally understand what the term flash means technically, but when racers use it as a verb or adjective to describe their technique it becomes a little gray for me.

 

I think that would be called brake stall. I don't think it would work well for drag racing. I think it would be difficult to control your RT doing a brake stall.

 

Opps forgot about that. Yeah they took some TM out but at the time they could not touch the TCM still.

Anyway the smash it got me to a best 2.04 prior to the tune. All 60ft times regardless of tech where 2.15-2.04. The lower times tended to be the smash it rotine.

After the tune the best I was able to do with the smash it technique was a 2.01. Preloading to like I said 1000-1200rpms got me a 1.98. Differnece in ET a 12.92(smash) to a 12.82(preload).

 

My problem with launching from idle is my RT's are all over the place. Power braking helps me with RT control.

My plan is to get a separate tune stored on my lab top with HP tuner. For drag racing I will set the idle up to 1200 rpms. Then I can just use the smash the gas technique again.

 

Now that is an idea.

 

And if my RT needs adjusted I could just turn the idle up or down.

 

If I can interject........... do not worry about your reaction time. You need to get your launch down first.


Power braking vs flashing the converter

Power braking is holding the brake while increasing the RPMs to just about where the rear lets loose a gradual building of RPMS
Flashing is holding the brake while you quickly bring up the RPMs and release the brake at the same time.

A really quick & dirty
You need to heat the rear tires, a short dry hop will do. If you have been sitting in the staging lanes put on the AC to run the fans & drop the engine temp. On a well prepared track you can heat the rear tires and flash the converter to get the quickest 60 foot times. Stage shallow just light the second light & stop. You want to launch with just a little bit of tire spin so the tires hook up. Concentrate on what you are doing.... do not look at the other lane.....watch the tree and practice, practice & practice. It is very helpful if you make notes on your time slips so that you can compare what you did and how will it works. Good luck

 

The only reason I go to the strip is to win the bracket race. Actually when the rules allow it I enter two different brackets. I live and die by the RT. Anything under .060 and you are on your way home or on the trailer as they say.

Actually not even sure if you are talking to me.

I am not one of these fellows that goes to the race to see how fast I can go. I do that but I am there to win the race. It is just a hobby but I am very serious about winning.

 

why the a/c ? i've always used the heater to 'drop' the engine temps.

usually, i've seen the a/c cause more heat to be generated by the engine, due to drag, etc.

while, the heater, simply uses the interior fans (blower) to pull heat from the heater core (small version of the radiator).

first time, i've heard to use the a/c to cool the car down, oh wait...yes the a/c will cool the car down and make it more comfortable to sit in but this is the first i've heard it will cool the engine/ drop engine temps.

i wonder if by turning on the a/c you are actually heating up the engine and causing the radiator fans to come on.

 

so basically, 'power braking and flashing' can be described as:

power braking gradually builds the rpms (begins to preload the suspension)
flashing quickly builds the rpms (causes the car to lurch forward during launch.

it appears flashing uses the brakes to keep the car from rolling off the line (if the car was sitting on a flat surface would you need to use the brake ?) and you floor it.

power braking uses the brakes to hold the car on the line while you 'load' up the suspension (requires more and more brake as more and more throttle is opened), well at least as much as you can with the stock brakes.

not nearly as fun a 'slamming' it into drive.

please, nobody take it personal but to me 'flash the convertor' sounds like 'drift' is to race.

 

Zig, using the A/C is to make the fans turn on. Since the fan speed is temp-controlled, it will keep the coolant temps down, not increase them.

Turning the heat on also is an old trick that also works to keep coolant temps down. Using a low temp thermo largely negates the need for either technique.

I'm not sure I understood your last comment, but "flashing the converter" is a pretty common term. Brake stalling can smoothe reaction times, but doesn't seem to offer much improvement in launch times (60 ft.). Not to throw flame on the fire, but I believe this is related to TM.

 

ok, understood. but since, as you say, the fans are temp. controlled, by turning on the a/c you are increasing the coolant temp causing the fans to come on.

yep, olds tricks and concepts still largely apply.

if this is true why are guys needing to turn on the a/c when standing in line.

a proper temp therm. will negate the need for additional aids to keep the car temp. under control.

my last statement 'flash the converter is like drift is to race' was simply a funny. similiar in concept as hammer is to nail, and rain is to wet, etc. etc.

hhmm.. maybe we have two different methods of acceleration after launch.

no fuel to the fire taken.

so tm has a dramatic effect on launch ?

 

When at the strip please do not turn on the AC. You will leave water on the track that you or the guy behind you might hit. The NHRA official at the start might not catch it and you can cause serious problems for someone. Every track I have ever been to has at some point instructed racers not to turn on their AC.