OK I just spent the last two weeks researching calling and digging for info on turbo charging my 99 dohc. From what I have learned fuel mapping alone works well with the ecu timing in moderate boost ranges. A fuel pump upgrade and maybe slightly larger injectors will help but are not needed. It also does away with the need for an FMU. greddy, apexi, megasquirt are a few that I know of...although MS is a stand alone system...much more than I will need. thats what i know of so far...what i need to know is. which is the most reliable to go with. obviously any company you call will tell you their product is the best. I need a unit to control the fuel system from idle all the way to red line. My stock ecu should be fine for now. Any suggestions anyone?

 

Mopar makes a perfect PCM for this type of aplication I do belive. Megga Squirt is an awsome system I hear though.

 

Neither the Mopar or the AFX PCMs are good for turbo aplications, they run way too rich for a turbo. The stock PCM is good for mild boost. If you want to go higher, the mega squirt is really the cheapest and best option.

 

I am thinking about running the MS for fuel only....and if I move to bigger power later it will be an easier transition for me.......does anyone know if I install the MS to control my fuel will I still need a high volume pump and larger injectors?

 

The stock fuel pump and injectors are good for mild boost. It will not hurt to have the high flow and bigger injectors though. Just remember you are going to have it dyno-tuned if you go with the MS. Tuning time is not cheap and make sure you have everything on the car when you do it. If you go with the stock Fuel pump and injectors, tune it and then wanna up the fuel pressure and injectors, your gonna have to tune it again.

 

The Mopar and AFX PCM's don't run too rich for a turbo, they actually run leaner than the stock PCM's. The problem with them is they advance ignition timing, where a turbo wants timing retarded.

The stock fuel pump will only provide enough fuel up to about the 180-190 HP range. This is something you don't want to be the weak point... $110 for a Walbro 255 lph pump is going to keep the flow you need until you are up in the 350+ HP range. Do the calculations on your own and figure out how much fuel you'll actually need though...

Larger injectors by themselves aren't going to solve anything. It's not just about getting more fuel, it's about getting the right amount of fuel. You can go with a rising rate fuel pressure regulator, a 1:1 regulator, 2:2 regulator, etc. and adjust base fuel pressure to suit your needs. Or you can go with a standalone setup like Megasquirt, which is the route I would go. Even with a "mild" amount of boost, stock injectors on the stock PCM is just stupid. The PCM doesn't know that you've got all this extra airflow, so why would it add more fuel (injector open time)? Lean burns melt pistons.

Speaking of boost, you're aware that the stock MAP sensor freaks out under a positive pressure, right? There are a couple of ways around it. Honestly though, the MS setup has come so far in the last year or two and is by far the most affordable, most capable standalone unit available for the Neon. Hard to pass up. Did I mention it can now do real-time wideband O2 sensor tuning?...

Best of luck!