DIY: Clutch Start Switch Bypass
#16
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The clutch will still spin with the flywheel as you turn the key. But as long as the shifter is in neutral first, the input shaft will not turn and move the car at all and so called draw more amps.
#17
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when we say clutch...we should separate it from clutch disc and pressure plate...sure the pressure plate and flywheel is turning no matter what...but the disc is what connects it to the input shaft thus powerflow into the transmission...
when we engage the clutch (pedal) ...or disengage the clutch disc...it removes it from the other parasitic drag of the input shaft...clutch disc...and the rest of the counter-gears in the trans still spinning... thus less amperage for the starter to work...
even in neutral with the clutch (pedal) disengaged...or clutch disc engaged...though we have no movement...the input shaft is still spinning...and so is the counter-gears within the trans...until we engage a synchro which links us up to the output shaft...thus output...
does that help or make sense?
when we engage the clutch (pedal) ...or disengage the clutch disc...it removes it from the other parasitic drag of the input shaft...clutch disc...and the rest of the counter-gears in the trans still spinning... thus less amperage for the starter to work...
even in neutral with the clutch (pedal) disengaged...or clutch disc engaged...though we have no movement...the input shaft is still spinning...and so is the counter-gears within the trans...until we engage a synchro which links us up to the output shaft...thus output...
does that help or make sense?
#19
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funny you should mention alternator...dont know about subaru alternators...but fords been providing pcm input to field the alternator...their theory was to reduce the amount of amperage to the starter during startup as well as to fully regulate the output of the alternator depending on conditions/ load/ charge of battery...
anyone know if the subie is a basic normal alternator hookup?
anyone know if the subie is a basic normal alternator hookup?
#20
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Subies have basic setups, nothing I've heard of for field generation in Subaru ECUs for starting as far as I know. But I know that the newer cars have higher output alternators than older models back then. I can imagine Ford having PCMs to field the alternator because of the larger size V8 engines.
#23
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this is one of the many reasons why a clutch 'safety' switch is used at start up. you release your clutch (pedal depressed) for less load on the starter when cranking. and as for people saying leaving it in gear when you park. its so that your car dont jump when you crank. its a clutch safety switch for a reason same as an automatic theres a safety switch in the shifter so you dont crank it in gear. regardless of safety people have there own opinions as how they wanna run their car. less amperage on the alternator dont make sense because the car aint running. its actually taking amperage from the battery guys. witb more amperage to put out to the starter to crank the faster the battery will die at crank without the engine running. sooo makes sense as to why its better to crank with clutch pedal depressed. but in reality THAT much of a load isnt gna kill your battery unless youre cranking for about 2-5 min straight. bottom line, if you do this, take precaution and make sure your car is in neutral before you crank!!!
#24
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this post is old, but another reason to do this - some cars have weak main thrust bearings, like 2G DSMs. And even Miatas. The pressure of you pushing on the pressure plate during a no oil pressure start up can wear the bearings, and give you a bit of crankwalk later. Not sure if Subaru ever had that problem, I've never heard of crankwalk problems.
#25
this post is old, but another reason to do this - some cars have weak main thrust bearings, like 2G DSMs. And even Miatas. The pressure of you pushing on the pressure plate during a no oil pressure start up can wear the bearings, and give you a bit of crankwalk later. Not sure if Subaru ever had that problem, I've never heard of crankwalk problems.
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