excuse my ignorance in the turbo department, but can someone explan the fuel programs you can get when you get your ecu reprogrammed...1 bar- 4 bar programs...im confused..4 bar seems to be in the larger turbo setups, but whats the difference?..does it flow more fuel to the injectors?..thanks for the help..scott

With the JWT ECU you can have two fuel programs: 3-BAR, or 4-BAR. The stock system runs at 3-BAR, which will allow a certian amount of fuel to spray through the injectors at full duty cycle. If you upgrade to the 4-bar program, you will need a new fuel pressure regulator that will increase your fuel pressure to 4-BAR which will in turn allow the injectors to flow more at full cycle.

without actually knowing what you need by getting on a dyno with a wideband o2, is there any general rule for when the 4 bar program should be used? Above a certain amount of boost, above a certain amount of power etc? I realize it'll always be different depending on the situation, but what are the rough guidelines of where the 4 bar program becomes necessary?

Originally posted by PDX S2000
without actually knowing what you need by getting on a dyno with a wideband o2, is there any general rule for when the 4 bar program should be used? Above a certain amount of boost, above a certain amount of power etc? I realize it'll always be different depending on the situation, but what are the rough guidelines of where the 4 bar program becomes necessary?

Above about 350 whp, you will need the 4 bar program.

T3/T-04E hybrid with the 0.82 A/R turbine housing will need a 4 bar program above about 15 psi.

T3-T04E hybrid with the 0.63 A/R turbine housing, and T-28's (any spec) can make due with 50# injectors and the 3 bar program.

4 bar program with 50# injectors is good to about 23 psi with a T3/T04E hybrid and the 0.82 turbine housing. That should be about 400-410 whp.

Rob