As with everything else race car related, "it depends". I know people who get their best footbrake launches from idle or a little over to people who come up on the converter more than me!
I put most of the emphasis on reaction time and that determines how high I bring the converter up from dead idle after I stage. That is normally 3,200 to 3,400. I can go a bit higher. But some people come up on the converter and bump into the stage light.
When I launch, the converter flashes to between 5,000 and 5,500, depending mostly on the weather and a little on if the car is set on "kill" or "bracket mode".
The looser the converter, the higher you can bring the rpm's up before "creeping". Brake system condition is also a factor. If your rear drums are starting to glaze, they will not hold the car as well. I found that periodic, very light sanding of the rear shoes helps. That's also when I check the brake adjustments and swap slicks from side-to-side.
I believe that rear brakes are more important in holding the car on the line than the fronts. If you can "harness" the power going to the rear tires, it will hold better than the skinny, small contact patch fronts regardless of how big & strong the FRONT (edited) brakes are.
A 10" converter rated at 5,500 stall just doesn't sound right. How high the converter flashes depends on torque, carb accelerator pump circuit, car weight and some other stuff. I have an Autometer playback tach. That is one of the best "tools" I ever got because it shows what the engine rpm's are actually doing rather than what you "think" it's doing. One example is that it's possible to actually see a flat spot (to a certain degree). (Unfortunately, I never got the program that would let me print out the graphs.) The converter won't flash as high as when it has a quick, clean & steady rise in rpms. When you see the converter flashing higher, than something is working better - i.e.: better air, better carb tune, water temp is more "compatible" with the carb tune-up, etc. But the converter still needs to be in the ballpark for your engine combo and it's potential.
Like I said, with all the variables, "it depends". But off-hand, if your engine can handle it, I'd consider a smaller/looser converter. I just never heard of a 10" converter "rated" that high. 5,500 would be 8" territory. But the "rating" is just a ballpark figure. More torque/big block will flash more than less torque/small block.
Last edited by Locomotion; 05/18/13 11:00 PM.