Old cast cartech FMU VS. New billet BEGI FMU
#3
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Differences to the end user? The billet one is alot prettier. Corky said the new model is easier to produce, but both function identically.
#10
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in a nutshell:
throw a FP gauge on the fuel feed line.
then back the top allen-screw out all the way.
start the car and make note of the idle, 35psi.
remove the vacuum line to the APFR and kink the line so as not to stall.
then note the fuel pressure, most likely 50psi.
adjust the top screw to make that pressure 55-60psi. (if no o2 clamp is used)
replace the vacuum line.
stop the car, turn it to ON, jump F/P and GND.
Clamp the return line down with a wrench.
note the max pressure the the pump. (if stock 70-80psi; HP 120-130psi)
move the fuel gauge to the driver windshield. (need about 4' of fuel line)
tighten the needle valve all the way in.
get in 3rd gear and boost the hell out of it. note the psi level.
back the needle valve out and try again to reach the desired psi level.
if you need help determining fuel pressures based on power levels and injector size read my FAQ.
Corky has his instructions on his site as well.
throw a FP gauge on the fuel feed line.
then back the top allen-screw out all the way.
start the car and make note of the idle, 35psi.
remove the vacuum line to the APFR and kink the line so as not to stall.
then note the fuel pressure, most likely 50psi.
adjust the top screw to make that pressure 55-60psi. (if no o2 clamp is used)
replace the vacuum line.
stop the car, turn it to ON, jump F/P and GND.
Clamp the return line down with a wrench.
note the max pressure the the pump. (if stock 70-80psi; HP 120-130psi)
move the fuel gauge to the driver windshield. (need about 4' of fuel line)
tighten the needle valve all the way in.
get in 3rd gear and boost the hell out of it. note the psi level.
back the needle valve out and try again to reach the desired psi level.
if you need help determining fuel pressures based on power levels and injector size read my FAQ.
Corky has his instructions on his site as well.
#11
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Ok, follow all that, but adjust fuel based on your wideband gauge (and log). Use the pressure gauge just to ensure that the adjustment to the FMU resulted in an actual difference in fuel pressure. The actual fuel pressure numbers aren't important; fueling he motor properly is.
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