Okay, so some of you know I bought an 04 Auto RX8 about a year ago that wouldnt start. Trying to get it running I have replaced the fuel pump (housing was cracked, replaced with used pump), replaced the starter with one for an 07 (2kw), installed an Optima RedTop battery, replaced plugs, swapped to an LS ignition, and replaced the ESS sensor. I just recently got access to another RX8 at a parts yard that I was able to pull the MAF sensor, fuel pump resistor, and multiple relays from. I swapped them with mine and it still wouldnt start so I put my MAF sensor back on. Thinking it may be fouled plugs I jacked the front end up (remember this part, front was about 1.5ft higher than the rear) and swapped in a fresh set of plugs. It started on the second try. Let it warm up and then shut it off and tried to restart. First warm resart took 3 tries. Then I was successfully able to start it warm 10 times (each time took a few seconds but happened on the first key turn). This is the first time its ever started warm. I was going to do some exhaust work on it today so I jacked the rear up and set it on ramps, and then tried to start it. No joy. What would cause it to start when the front is 1.5ft higher than the rear but not start when its level?

TL;DR: Bought a used 04 RX8 with starting issues. Replaced a bunch of parts, including ignition, used fuel pump, etc. Car takes 30-45 minutes of jumping to start cold and hesitates and wont start hot if on level ground. But car will start 4/5 times if front is higher than rear of car. What could be wrong?