I think a properly sized turbo and just a good stall rate torque converter will still allow an SC400 to bolt off the line.... Supercharging may just cause traction problems at launch with an aggresive T.C.... I think a properly sized 1uz-fe turbo system would keep up with the supercharger system and may even beat it. The key is having the higher stall rate torque converter in combination with the turbo setup... The torque converter will take care of your launch speed until the turbo boost comes on..
Example: With my Precision industries "dragon torque converter" my rears can still break loose some with out the use of my Nitrous system...Purely N/A my SC4 really bolts 0-30mph from a dead start all because of the aggressive torque converter stall rate 2200 (I think)... All the outside mods such as exhaust, headers, ECU piggy, and intake really just helps your topend power out...TC is all about lowend torque....However, after 30mph you will get slow, you will need nos, you will need a turbo, or you will need a supercharger setup or else you will get worked over... The 4.0 liter 1uz-fe N/A just simply does not provide enough umphh to get the heavy SC4 moving in a quarter mile sprint...