You should be able to buy an LT4 car for 2-3k less than an early ZR1... if this is the case, add the 3k you spend on your ZR1, plus another 2-3k, and you have a supercharged LT4... figure a good 50% gain over stock, and we are talking 500-550 HP... I think that would suffice to run your ZR1 down... When adding up the numbers do it by total cost... that is car+mods.