1991 ls motor. my block is FRESHLY rebuilt. i just hot 5700 miles on it. oversized jdm type r pistons, 2 layer head gasket, ummmm the head is stock internals. with 98 ls cams that are more aggressive and give a little more umph. im using a stock ecu that hits 7 grand. i feel great power from a dead stop to redline . as the same in 2nd 3rd and 4th. as if it want more rpm. i have a jdm b16 s1 tranny. gearing is awsome in there. i figure if i can get this bad boy to red line at 8 it would run a bit faster and put furure bolt on's to it max potential