AMC 150 I4 built to 2.7L, Weber 38/38 DGASM 136hp/173ft-lb 1984 Block
Took the engine out, had it bored out and got longer forged rods and pistons. 2.7L was the final number. :-)
They said I should be able to handle 6,500 RPMs without any real issue.. but it will get shaky at that range. lol. I just stick to the stock 5,200 RPM redline range.