Going lean!!!
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Teching In
Joined: May 2016
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Going lean!!! Issue I'm having is the car going lean on the highway. Its fine cruising, but if I slow down and pick up speed again the air/fuel gauge swoops to the lean side and the car shudders and hesitates. But if I floor it the car has no problem hauling ***. I hooked up a fuel pressure gauge and it measured 62 psi at idle and 62 while cruising. When it shuddered it maintained the 62 psi as well. No check engine light has come on yet, which makes it more confusing. Some of the engine mods are the LSA blower at 9 psi w/ ls9 cam and the small bore LSX ls3 heads, and 80lb injectors. Also running the 4l60E with a 3600 yank converter.
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Joined: Jun 2003
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Issue I'm having is the car going lean on the highway. Its fine cruising, but if I slow down and pick up speed again the air/fuel gauge swoops to the lean side and the car shudders and hesitates. But if I floor it the car has no problem hauling ***. I hooked up a fuel pressure gauge and it measured 62 psi at idle and 62 while cruising. When it shuddered it maintained the 62 psi as well. No check engine light has come on yet, which makes it more confusing. Some of the engine mods are the LSA blower at 9 psi w/ ls9 cam and the small bore LSX ls3 heads, and 80lb injectors. Also running the 4l60E with a 3600 yank converter.
Don't know if product literature is accurate or not, but I have read the large injectors 80 and up are slower to react - makes sense as described. Whether true or not?
Might be in your tune instead or injector scaling is off. SD tunes IMO give the most crisp throttle response with FI. I would have your tuner data log and reexamine your tune.
Thread Starter
Teching In
Joined: May 2016
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I was able to get the tune checked this past Saturday and of course the car wouldn't duplicate the problem like it was before hand. But he did notice that the car did need more fuel in some areas and had also adjusted the timing. As far as the size of the injectors I cant answer on the size, due to me buying the car already built.
