The Tragic Tale of ElSuperPinto

Short answer: Because the 4th-gen Prius is brake-by-wire.

Long answer: Because the 4th-gen Prius is brake-by-wire, meaning that the master cylinder isn't so much a master cylinder, as it's a hydraulic multi-purpose device with the primary function being to give the driver of a Prius the feel of normal hydraulic brakes. The module on the side of it is there to use inputs from various sensors, including the yaw rate sensor in the steering column, the brake pedal position sensor, various pressure sensors, the wheel speed sensors and so forth and so on to decide how much of and which type of braking to apply. The "which type of" braking comes into play because the majority of the time, the Prius isn't using it's hydraulic system and brake pads to stop the car, it's using the electric motor for regenerative braking, which not only slows the car down, it also recharges the high voltage battery. While stepping on the pedal connected to that master cylinder does cause brake fluid to come out through two of the three ports on it, it's only designed to do so under certain circumstances, in others, it bypasses internally and sends the fluid to a "stroke simulator". In addition to all of this complication, there's also the fact that while the assembly I got DOES include the brake booster, it's not the WHOLE brake booster. If you look up at the hydraulic diagram, you'll see the mention of a "brake booster pump assembly". That's not internal to the assembly I ordered and received, it's halfway across the engine compartment. That guy gets fed brake fluid via gravity via the nipple on the side of the master cylinder reservoir through a hose, and then sends pressurized fluid back to the booster's inlet port. Without that, no boost.

On top of ALL of that mess, when the Prius master cylinder's control module goes into failsafe mode, it does so by reverting to behaving as a manual brake master cylinder, meaning it won't energize any of it's various internal components to do a damned thing to help, and even after consulting a Toyota master technician I've known ten years and putting our heads together studying the various wiring diagrams, hydrulic diagrams, and parts catalog pages, neither of us is convinced it could or should be tried. The one thing we both are sure could be done is using a relay that's triggered by the stoplamp switch to turn the accumulator pump on and off, but we can't be sure the pressurized fluid would actually go where we want within the master cylinder assembly.
So... if you'll remember, I'd hit this roadblock in my quest to have power brakes with the big ol' Four-Point-Six-Liter-Chevy-eater under the hood...

There's something I wasn't aware of though.

https://www.stangnet.com/mustang-forums/posts/9279066/ There's @90sickfox providing the answer to a question he probably didn't know I was asking.

I can run an ugly-ass hydroboost unit (which I still don't want to do for aesthetic reasons) AND not have to add an otherwise unnecessary power steering pump to my engine by hiding a Volvo electric power steering pump inside my fender.

I'm adding to the list of crap to get at the junkyard.
 
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In other surprising news... my old man actually dug a path through all of his junk in the garage to the Capri this week... I don't know exactly what he's up to...
 
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So... No ElSuperPinto progress... yet. @90sickfox just bought my Ford Racing tach and I'll be using that money for the head bolts and a gasket set so I can start building the Mark VIII engine.

In the meantime, more progress has been made on the Toyota's Overland build. I now have LED bulbs in every internal light fixture, an ultra-bright overhead light to use to light up the back of the vehicle when the hatch is up, attic storage, and a rear charging/power panel.
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For those not in the fox body thread, here's the BMW N63 V8 I'm completely re-wiring at work:

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If you're wondering why so little gets done on my :poo: these days, well, there's your thousand words as to why.
 
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Those engines always amazed me with the turbos in the valley. Pretty smart set up...but complicated to split the intake to opposite sides. That thing is almost like two engines smashed together.

Rodents do love the sweat taste of European vehicle wiring.

The Toyota is looking good. Form and function...very nice man !!!
 
Those engines always amazed me with the turbos in the valley. Pretty smart set up...but complicated to split the intake to opposite sides. That thing is almost like two engines smashed together.
The electronics actually run it as two engines, it has a separate DME (PCM) for each bank, and they're linked together through a single harness.
 
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There supposed to fly by now wtf?


I'm ready for some 'Over Land' adventure....
Get the beer tap in and your ready to go!
 
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Here's an update to the thread where I bitch about BMWs, show the status of my 4Runner's mods, highlight why that 2010 Taurus in my parents' driveway is the bane of my existence and show the rare times I work on the Suburban or they Hyundai my dad drives...


Are ya'll ready for it???

II STUFF HAPPENED!

No joke. Look at all these goodies! Valve covers, coils, and the ignition harnesses from an Aviator, fuel rails, alternator, and coolant crossover from a Continental, an EDIS-8 from a Town Car, and a huge pile of bolts!!!!
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Of course there is, I have a 4Runner. Had you mistaken me for a mere Jeeple?
Took the 4Runner on an off-road adventure for the first time today. There's a 40-mile stretch of red dirt roads that cuts through the Texas hill country and crosses three rivers and several creeks (no bridges), and I've been itching to try it for months. Didn't even come close to getting stuck, had a blast, and rolled with some guys in Jeeps for awhile after I waited on them to get one of their Wranglers un-stuck in one of the river crossings.

Here she is after coming out the other side and back to pavement:
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Today was a good day.
 
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That's awfully clean! :jester:

I used to have an 87 Ranger STX 4x4 regular cab short box. In my hometown we had a place where we could go offroad and play around like that. The first time I went through there with my Ranger I had a buddy who decided to ride in the back holding onto the roll bar. I hit a mud bog and when we come out the other side and stopped, he jumped out of the back of the truck and looked like he buried himself in mud. There wasn't a clean spot left on the truck, except maybe where he was holding on to the rollbar. That was just one of our "adventures" :rlaugh: