LS376/480 RPM limit
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Teching In
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LS376/480 RPM limit I'm from Russia and my english not very well..
I have new ls376/480 for drifting, and in drifting a lot time engine working in RPM limit.
This is my project
The problem is the RPM limit is very slow.. when I get limit my drift die, it works not like "tutututututu" like "tuuuuutuuuuuutuuuuuu"
I connect computer to OBD2 and read stock ECU, the RPM limiter intervals are 80 RPM, so it should work great.. fuel pressure 62 psi... ignition stock...
Sorry for this not understandable text
I have new ls376/480 for drifting, and in drifting a lot time engine working in RPM limit.
This is my project
The problem is the RPM limit is very slow.. when I get limit my drift die, it works not like "tutututututu" like "tuuuuutuuuuuutuuuuuu"
I connect computer to OBD2 and read stock ECU, the RPM limiter intervals are 80 RPM, so it should work great.. fuel pressure 62 psi... ignition stock...
Sorry for this not understandable text
Thread Starter
Teching In
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Thread Starter
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On The Tree
Joined: Mar 2012
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In your description, best I understand, you are saying it is not bouncing off the rev limiter "tutututu" but, dying off entirely "tuuuuuuu". I would think it is first a fuel delivery problem, not enough volume of fuel, either poor fuel pump, blockage in fuel line or injectors. Could also be voltage problems at fuel pump, do you have a large electrical wire to fuel pump? The BMW fuel pump should give enough delivery but, maybe there is a electrical problem in system.
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Thread Starter
Teching In
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In your description, best I understand, you are saying it is not bouncing off the rev limiter "tutututu" but, dying off entirely "tuuuuuuu". I would think it is first a fuel delivery problem, not enough volume of fuel, either poor fuel pump, blockage in fuel line or injectors. Could also be voltage problems at fuel pump, do you have a large electrical wire to fuel pump? The BMW fuel pump should give enough delivery but, maybe there is a electrical problem in system.
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You cannot rule out electrical. We built a gen1 motor with EFI onetime and it ran flawlessly on the dyno, then when in the car, it wouldn't RPM, after many hours it was found that fuel pump connector was begining to fail and voltage was dropping below 11 volts. This motor ran fine until about 5500rpm.
The other thing I would check is for plugged injectors or fuel line problems, did you make sure system is 100% clean before starting up new installation. Good luck.
The other thing I would check is for plugged injectors or fuel line problems, did you make sure system is 100% clean before starting up new installation. Good luck.
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Teching In
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You cannot rule out electrical. We built a gen1 motor with EFI onetime and it ran flawlessly on the dyno, then when in the car, it wouldn't RPM, after many hours it was found that fuel pump connector was begining to fail and voltage was dropping below 11 volts. This motor ran fine until about 5500rpm.
The other thing I would check is for plugged injectors or fuel line problems, did you make sure system is 100% clean before starting up new installation. Good luck.
The other thing I would check is for plugged injectors or fuel line problems, did you make sure system is 100% clean before starting up new installation. Good luck.
You check this problem in the run or in static with ignition "ON"?Yes everythink was fine with fuel lines, but know I think maybe fuel regulator broken?
This how fuel works, in the right down corner is a half image of regulator:
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Teching In
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So I don't have speedometrThis how it arrived to me, maybe this broken one was a speed sensor?
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Staging Lane
Joined: Jun 2012
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From: Hutto / Round Rock, TX
You should check the fuel pressure at wide open throttle under load. The fuel pressure can be ok with key on and engine off and even at idle but volume and pressure can drop at wide open throttle.
You NEED to connect the VSS to the ECU. Your post #13 is the VSS. It will not run well without it connected. Grab a new sensor. Plug it into the ECU. The ECU puts out a 4000 pulse per mile signal.
The speedometer in the car does not need to be connected but the VSS to the ECU does.
The speedometer in the car does not need to be connected but the VSS to the ECU does.
On The Tree
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If your using GM performance ECM you don't need VSS. I say redo fuel system with late model Corvette fuel filter with built in pressure regulator and get rid of present setup. You can mount filter at back of car and run single fuel line to intake fuel rail no return line just like C5/6 Corvette. This is what instructions for LS480 from GM recommend.
