ok im going to be going turbo soon and im going to use a fmu for a few weeks till i can get the car tuned so my ? is what ratio shim should i run with my fmu on my car i plan on runing 8-9 psi for now
Depending what year the eco is, it wont matter what the ratio is.
2003-2005 ecos had a PE delay of like 6200 rpm, which means no matter what you do fueling wise, the computer will achieve 14.7:1 by dialing back pulsewidth. If you have a 2002 or early 2003 PCM, you may be able to get away with the FMU until it's tuned, but no one hear can tell you what ratio to use.
I would suggest starting with a ratio that puts you at a max fuel pressure around 80-85 PSI, as the pros here have said that's where our pump clips. If it's rich, obviously step down the ratio. Personally I wouldn't run it hard until it's tuned, at least the PE delay threshold lowered...
well my pcm in the car is out of a 03 but i have my 02 pcm still too i can put back in
i guss ill start with a 10.1 ratio disk
Keep in mind a 10:1 FMU will have you're fuel pressure over 120 PSI @ 8 PSI of boost on stock static pressure - not good! If you can drop the static pressure to 30-35 PSI you might be able to get away with it, other wise, try to keep the in-boost pressure under 80-85 PSI