How to run LS2 with LS1 alternator?????
How to run LS2 with LS1 alternator????? I have steering box clearance issues which is why I chose the F body alternator. It does not have the duty cycle output which the E40 ecm uses to determine electrical load therefore throwing out code P0622 - Generator F-Terminal Circuit. It is reaking havoc on my idle as it is seeing a duty cycle of 0% and is trying to raise the idle to fix it. Question for the gurus is can you program out that circuit with HP tuners or successfully cheat the input? If not either I need to figure out how to fool it or buy another brand new alternator from a vette or such which has the duty cycle output but I would rather not as I already have this one. Just to clarify, I am not asking how to make the LS1 alternator charge as that horse has been beat dead already. Definately going with a LS1 pcm the next go around as this LS2 ECM sucks for conversions.
I have steering box clearance issues which is why I chose the F body alternator. It does not have the duty cycle output which the E40 ecm uses to determine electrical load therefore throwing out code P0622 - Generator F-Terminal Circuit. It is reaking havoc on my idle as it is seeing a duty cycle of 0% and is trying to raise the idle to fix it. Question for the gurus is can you program out that circuit with HP tuners or successfully cheat the input? If not either I need to figure out how to fool it or buy another brand new alternator from a vette or such which has the duty cycle output but I would rather not as I already have this one. Just to clarify, I am not asking how to make the LS1 alternator charge as that horse has been beat dead already. Definately going with a LS1 pcm the next go around as this LS2 ECM sucks for conversions.
I might need to run an F-Body alternator on my BMW swap. Engine is a 2006 GTO LS2 with the E40 PCM. The F-Body unit is apparently smaller and has a more compact rear bracket. The range of motion of my drivers side motor mount is limited by the larger rear bracket of the GTO's alternator.
I can't find any definitive information regarding the use of a one-wire F-Body alternator in place of the stock two-wire GTO unit with regard to both wiring and the E40 duty cycle issue referenced above.
Any help is appreciated.
Thanks.
Tipsy
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I have used a 2008 CTS-V alternator, a common aftermarket brand and a F-body alternator on my LS2 with LS1/411 PCM. The CTS-V expected PWM and since the 411 does not support that, the alternator only put out 13.7 volts which was a bit low.
The F-body works perfectly, but seems bigger in size than the CTS-V alternator.
I would go to a well stocked parts store and have them bring out different LSx alternators for you to compare their sizes. Maybe CTS-V, Corvette, GTO.
The F-body works perfectly, but seems bigger in size than the CTS-V alternator.
I would go to a well stocked parts store and have them bring out different LSx alternators for you to compare their sizes. Maybe CTS-V, Corvette, GTO.
Corvette won't fit your bracket. It's bigger.
Been there, done that but in reverse. I have a Camaro operating system that doesn't use the duty cycle input.
I'm doing a harness from a truck for a swap. It has the duty cycle wiring. So maybe look into the truck alternators? I'm not sure if they fit an Fbody bracket, but I think they do?
Been there, done that but in reverse. I have a Camaro operating system that doesn't use the duty cycle input.
I'm doing a harness from a truck for a swap. It has the duty cycle wiring. So maybe look into the truck alternators? I'm not sure if they fit an Fbody bracket, but I think they do?
Last edited by RonSSNova; Mar 22, 2015 at 10:26 AM.
