550s leaning out, need help!

figgie

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Mar 30, 2005
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grimreaper;1104170 said:
good stuff, wonder why a few of the old timers say its one of the dumber mods ?

figgie, do you know if the fuel pump switches to 12v on start up or possibly when the motor is cold enough to warrant the warm up cycle?

im dgging through the manual but i cant find anything that says when and at what parameters the pump runs on 12v

could not tell you. that is based on code.

as for being a dumb mod. just in about 98% of the installs, it surely is.
 

grimreaper

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Jul 2, 2008
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when would it not be?

and to add, i feal what your talking about with the switch, soon as i drop the hammer or start building boost, half second or so of this void.
 

figgie

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Mar 30, 2005
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grimreaper;1104342 said:
when would it not be?

and to add, i feal what your talking about with the switch, soon as i drop the hammer or start building boost, half second or so of this void.

half second? less than that unless the relay is almost out the door.
 

grimreaper

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ill pull out the ol volt meter in the am and check her out, my internal clock may be off, but i can definatly feel it when slowly pulling through second then going wot.

you might be familiar with the ride, its murkats old one, jay did one top notch job on her....

not to push it but im assuming the 12v mod would be more applicable towards standalone users or is there anything to signify the different pumps other then oem, not taking to voltage jumps on a whim?
 

figgie

Supramania Contributor
Mar 30, 2005
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Twin Cities, Minnesot-ah
grimreaper;1104354 said:
ill pull out the ol volt meter in the am and check her out, my internal clock may be off, but i can definatly feel it when slowly pulling through second then going wot.

you might be familiar with the ride, its murkats old one, jay did one top notch job on her....

not to push it but im assuming the 12v mod would be more applicable towards standalone users or is there anything to signify the different pumps other then oem, not taking to voltage jumps on a whim?


ahh you bought Jay's old car? very nice buy!

I know what you are talking about. That is not the fuel pump switching. That is more tuning (ie the need for an S-AFC or other piggy back). The fuel pump switching, only way you would really tell is by logging fuel pressure. You will see a slight drop in FP before the turbo kicks in.

As for tuning. Again Toyota is not as idiotic as people want them to be. The switch to 12v happens before the turbo has a chance to kick in. Low loads to med loads. If they did that while the turbo was churning away, they would have had major major warranty repair work to be done on countless dead motors ;)