Odd power loss at 5k rpms..
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Odd power loss at 5k rpms..
I got on the car a bit tonight (excellent weather) and for some reason it doesn't seem to want to go past 5k rpms.. It doesn't hesitate or anything, it just seems like it loses power. Ever since I did the th350 swap its been like that. Could it be the governor? Or something else like valve float? \= I heard auto valvebody TH350s wouldnt go past 5k rpms anyway because of emissions back then (even when manually shifting). Can anyone confirm this? Thanks in advance..
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It's just odd because with my previous transmission (4L60) it never did that, I could shift at like 6500 no problem.. Also, in park or neutral, I can take it past 5k rpms if I want, it's just under load it won't budge. So the transmission has nothing to do with it? Ps. thank you for the quick reply..
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I'd expect if it was the converter or trans itself, you'd
be talking about flare. But if it just sort of plateaus,
that is more likely the motor or its controls (if you were
soaking up 50HP in the frictions or juice, you'd know
about that soon enough).
Not sure what kind of motor/PCM you might have, but
can you look at spark retard, knock retard? Vibration
or acoustics of the wrong note could be false triggering
a spark pullout and act that way.
be talking about flare. But if it just sort of plateaus,
that is more likely the motor or its controls (if you were
soaking up 50HP in the frictions or juice, you'd know
about that soon enough).
Not sure what kind of motor/PCM you might have, but
can you look at spark retard, knock retard? Vibration
or acoustics of the wrong note could be false triggering
a spark pullout and act that way.
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I'd expect if it was the converter or trans itself, you'd
be talking about flare. But if it just sort of plateaus,
that is more likely the motor or its controls (if you were
soaking up 50HP in the frictions or juice, you'd know
about that soon enough).
Not sure what kind of motor/PCM you might have, but
can you look at spark retard, knock retard? Vibration
or acoustics of the wrong note could be false triggering
a spark pullout and act that way.
be talking about flare. But if it just sort of plateaus,
that is more likely the motor or its controls (if you were
soaking up 50HP in the frictions or juice, you'd know
about that soon enough).
Not sure what kind of motor/PCM you might have, but
can you look at spark retard, knock retard? Vibration
or acoustics of the wrong note could be false triggering
a spark pullout and act that way.
#13
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Probably not going to the event, I only go there to
run it and the big events are too packed to get many
passes in.
Thinking about this some more, maybe you are just
seeing the way a higher stall converter works. Mine
will sit at about 5000RPM for a good while and the
MPH moves while RPM doesn't; eventually it will begin
to rise but not for a while. Accelerating hard the
whole time.
Now, hanging and not accelerating, that's a problem.
But hanging at your peak torque RPM and accelerating
hard, that's what a higher stall speed converter is for.
run it and the big events are too packed to get many
passes in.
Thinking about this some more, maybe you are just
seeing the way a higher stall converter works. Mine
will sit at about 5000RPM for a good while and the
MPH moves while RPM doesn't; eventually it will begin
to rise but not for a while. Accelerating hard the
whole time.
Now, hanging and not accelerating, that's a problem.
But hanging at your peak torque RPM and accelerating
hard, that's what a higher stall speed converter is for.
#14
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^ You bring up a great point, and possibly overlooked it.. I'm going to orlando this weekend so when I get back I will do a little tune up (plugs are due) and I will take a few videos showing what it does. It could very well be what you said, but I cant verify MPH increase because I dont have a speedo hooked up with the TH350.. but I'll look into it. Thanks for the help bro!