Well, it varies a lot, I'll try to explain in detail.

Sometimes (5% of the time) the car will start on the first crank, sometimes it can take cranking for 10 seconds at a time 10-12 times over the course of 15 minutes before it will start.

The only pattern that I've been able to consistently find is that the problems gets worse as the outside temperature goes up, my coolant temp sensor reads accurately in link. I've tried increasing my cranking fuel adj in link to combat this but I've increased this value in 10% increments up to an extra 100% fuel while cranking with no noticeable change.

The interesting thing is that the car will always start eventually, it has never left me stranded and often times after cranking 10 or 12 times I'll turn the key and it will catch instantly and fire right up, there seems to be no pattern as to when this will happen.

When it doesn't start I can often hear it attempting to catch on the first try. With my starter turning at about 200rpm I will see readings as high as 400rpm while logging meaning that the engine is firing but will not produce enough power to start itself. Sometimes however it wont try to catch at all on the first try and just turns over around 200rpm

If the car doesn't start my wideband will read from about 12:1 - 14:1, these readings didn't really change when I increased my cranking fuel adj by up to 100%. I would expect to see richer AFR's which indicates to me that the injectors are just not receiving enough fuel while cranking to start the engine, even with a bigger pulsewdith.

A new test that I've been performing is to put a 10A charger on the battery for about 15 minutes to generate a high surface charge in the 13V range, I haven't tried it enough times to confirm that this works every time but it seems that the extra juice will help the car start on the first try. My battery is moderately healthy and will hold 12.5-12.6V overnight, it has also been tested with an ammeter at 625CCA, it was originally rated for 700CCA. Now I realize that a new battery may help the situation but I don't think that's the underlying cause of the problem here. I've also considered an AGM battery which will put out about 12.8-13V to supply all systems with a bit of extra power.

I tried to decrease my plug gap from 0.28 to 0.24 this weekend in case my ignition system was weak thinking that the smaller gap would help to produce a stronger spark but this had no effect.

The car will start first time once its hot, an interesting symptom is that it revs to about 2500rpm when started hot which seems quite high, I'm not sure if this is related.

A list of things I've checked / done to try to fix this issue:
- Rebuilt starter
- New power and grounds cables to starter (0 gauge welding cable)
- Additional ground from manifold and alt to chassis (4 gauge)
- New black body ISC
- Swapped MAF
- Triple checked for vacuum and boost leaks
- New PCV valve and hose to manifold
- Checked coolant temperature sensor
- Tested coils for resistance
- Tested and swapped two power transistors for resistance
- Tested injector resistor pack
- Tested injector resistance
- Opened AFPR and inspected diaphragm
- Pinched return line as stated above, pressure holds, no
leaking injectors
- Fresh caps when ECU was socketed two seasons ago
- Installed new exhaust (not really relevant)
- Increased 10V deadtime value in link to add fuel while
cranking.

One question that comes to mind is could I be flooding the engine? I've pulled the plugs after cranking 3 or 4 times and they typically have fuel around the outer ring of the plug but not on the electrode itself, also I would think I'd see a big puff of black smoke and really rich afrs after it finally catches and I'm not seeing that so I kind of ruled it out.

So there ya go, there's more info floating around in my head and I'll continue to post whatever relevant details I can think of. If you guys can help me fix this car without dumping a ton of money into parts I would be really grateful. I'm fine with going out and dropping a couple hundred bucks on a part if we can confidently agree that its going to fix the problem I just don't want to throw money at it and hope for the best.