brand new 1600cc injectors maxing out at 10PSI
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Joined: Aug 2005
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From: San Francisco
brand new 1600cc injectors maxing out at 10PSI
i have 2 brand new bosch 1600cc injectors, running a gt35r and at 10.5 pounds of boost, the injector duty cycle is at 98%. i have the bosch044 fuel pump so it should be plentiful. where is the excessive fuel going? the only other thing is the pump is getting about 0.5volts less than its supposed to, causing about a 1-4 psi drop in fuel pressure. what can be wrong?
im gonna assume you mean that just the secondaries are 1600cc, and the primaries are the stock 550's? I'd get a fuel pressure gauge ASAP so you know whats going on there, whether its a pump/filter problem or an injector problem.
Aftermarket pumps can also max out the stock pressure regulator; the walbro 255 i put in mine was just overwhelming the stock FPR with a constant fuel pressure of about 50 psi. I switched to MS at the same time tho, so I was able to tune around it til I got a better regulator, but its something to look out for.
Aftermarket pumps can also max out the stock pressure regulator; the walbro 255 i put in mine was just overwhelming the stock FPR with a constant fuel pressure of about 50 psi. I switched to MS at the same time tho, so I was able to tune around it til I got a better regulator, but its something to look out for.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
two things right off the top
when you say you get a 1-4 drop in fuel pressure, that isnt right a real bosch 044 should have enough capacity even with a little less voltage to keep up. is it a NEW pump? ive seen them wear out before.
second i have seen people get injectors that they thought were 1600, but really they were 850's or so. also the 1600's vary by like 10% or something, so you might want to get them tested.
i assume you've done the dumb stuff like both fuel filters?
when you say you get a 1-4 drop in fuel pressure, that isnt right a real bosch 044 should have enough capacity even with a little less voltage to keep up. is it a NEW pump? ive seen them wear out before.
second i have seen people get injectors that they thought were 1600, but really they were 850's or so. also the 1600's vary by like 10% or something, so you might want to get them tested.
i assume you've done the dumb stuff like both fuel filters?
