Quote Originally Posted by DieselNuts View Post
The Mach has an aluminum block and cast internals, correct? Before I got my Cobra I thought about a Mach1 but decided against it because of reading that 450 was the MAX you could run safely before building the bottom end.
yep, like I said Mach's and cobras have an industry standard for how far you can go before buying yourself a new block.

Cobras are alum blocks with forged crank/rods/pistons, machs are alum blocks with cast rods/pistons and a forged crank. The limit for a safe tune via FI on a stock block is 450-460...anything past there and you will not last long. but most people detune for 420-440!