engine wise, all I would invest in is, a ARP headstuds and a cometic .043" headgasket. The gasket will drop the compression to ~9.8:1. Crome and uber work nicely, you just need teh right copy.

Install the turbo kit, with some 450cc or bigger injectors then, goto me or mtber and get a good street tune. With a good tune ~250whp is VERY safe on stock internals. That is much more than 50whp.

Casper your ringlands cracked because of the vafc hack, it doesn't remove timing. timing causes detonation, which leads to your ringlands cracking.