Well I decide to finally go with the 12tz. I saw the abuse my 12tr took and I was convinced that OS makes them pretty strong. I had bought my 12TR engine used and abused and it had well over 10 gallons (minimum) through it and had never been cracked open, not once. I knew I would be getting the TZ so I took my TR out to track a few weeks back and ran it pretty lean. It didn't help that it was 95° out that day and after 3 hard laps she popped! And boy did she pop! I included some pics so you guys can see the damage, yeah it was pretty ugly but she went out fighting. That thing took some serious abuse and it ran strong till the end. Well its up on my shelf now as a testament to what can happen in these hot South Florida days. Ill be braking in the TZ soon and I just wanted to send out a quick thanks to all all you guys that chimed in on this thread!