What a converter flashes is dependent on quite a few things. One of which is anytime you put a 505" engine in front of any converter it's going to feel lose because of the massive torque a huge engine like that makes. My PTC 3500 flashes over 4000 with my torquey little 408 yet it doesn't feel lose when I cruise it. Remember also that converters are rated 2 ways. Brake stall and flash stall. Flash stall with a big cube block is almost always going to be quite a bit more than brake stall. Also remember this, taller tires weigh more so they'll cause the converter to work more, which equals more slippage and quite possibly more stall