Hey guys.... I was wondering if there is any difference between a 95 420A block and a 99 420A block? Strength wise? Making? Like will I have the engine light go on if I swap a 99 420A Block in?

Thnx!

I think the only difference is that you will be required to use two top halves of the crankshaft bearings for hte 95 version.

The 95 blocks are the better ones to use, because you need to put two upper halves in yeilding full groove mains. This increases the oil supply to the rod bearings. Esspecially 2 and 3 rods which get the least oil, and have the highest rod bearing failure rate. We implimented a program on all our new short blocks where we modify them all to except full groove mains. We main increase the diameter of selected oil passages as well. We countinualy update our engine building program to ensure the best performance.