I can say I bought a 440Source 4.15 crank kit thats in my 493. I checked the pistons with pins and rods using my brothers tools and they were all very close. So close I went with their balance on the kit and crank since I knew mine was a street eng that I would not be running hard that much and it has worked fine. Its been in my car since 2011 and no vibration at all at any rpm that I can notice. Course if I was going to be twisting it hard every weekend I would want to have it checked to be sure. Ron