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Discussion Starter #1
I am in the middle of a transplant to go from a vacuum assisted brake system to an electric assisted brake system.

Specifically removing the OEM Mkiii System and replacing it with a Bosch iBooster system.

Why?

Great question!

Advantages

1. More compact package

20200515_124741.jpg


2. When not in use, minimal power usage as the canbus is receiving and transmitting messages.

3. Engine failure will not cause brake failure.

4. On the very deep technical side, certain canbus message can adjust assist rates.

Disadvantages;

1. Not a drop in ordeal which requires custom adapter

2. Power requirements up to 30 amps.

3. Unsure of viability without a standalone.

On to pictures of the oem adapter and my designed adapter

OEM bosch ibooster adapter
20200512_092037.jpg


My design

MasterBrake_Adapterv2.jpg


3d printed
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received_1157083911312874.jpeg


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The 3d printed parts are for test fitment and mock up. If it works, the design will be going to CNC machining to be made out of 6061 Aluminum.
 

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1987 Supra Turbo R154 Pearl White, Blue Velour
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Now THAT is pretty damn cool. I love the idea of 3D printing a prototype! Will the 30amp requirement be an issue?
 

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Discussion Starter #3
Now THAT is pretty damn cool. I love the idea of 3D printing a prototype! Will the 30amp requirement be an issue?
It depends as it is transient. But it might press the stock alternator. I am upgrading mine as this is one of a couple things that will need a more stout alternator.
 

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1987 Supra Turbo R154 Pearl White, Blue Velour
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Well it's good you're updating the whole related parts chain.
 

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Cool shit there figgie !

On the power draw, unless you are in stop & go traffic a lot, or doing something like auto-crossing, you should be fine with either the stock alternator, or maybe a Cressida 80 amp, which is a direct bolt-in.

I am going to an electric vacuum pump to get around the low vacuum on my set up.
But I am also going with an MR-S electric power steering pump, that will task the stock alternator, so I went with a Ford 3G 160 amp alternator.

Just keep in mind that most aftermarket 'high amp' alternators need to be driven at a much higher rpm than a stock one, so you may need to look at over driving one, if you do need to go in that direction.
 

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Discussion Starter #8 (Edited)
@Piratetip

Yep! Another bosch unit eps. That one does take speed input as a way to control rate which is simple to do.

The brake is fairly simple stuff considering. :)
 

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Discussion Starter #9
Cool shit there figgie !

Just keep in mind that most aftermarket 'high amp' alternators need to be driven at a much higher rpm than a stock one, so you may need to look at over driving one, if you do need to go in that direction.
Thanks Gordon!

On the alternator, i have to match sonething like the new 5 or7 series bmw as i will also be going electric power steering along with a couple of other high amp pull stuff.
 

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Discussion Starter #12
What will you be using to control this?

Nice stuff man!
well i have a slew of MoTeC stuff that will be installed and they have the needed canbus.
This will be the next phase after the install.

The 3d printed part ALMOST worked except the holes where off by about 2mm (short) so now i need to get it printed one more time :/
 

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Pretty rad idea there. Would be interesting to see how the brake feel is compared to stock.

Also, I had no idea that the MR-S had electric steering. I was considering picking up a Prius setup if I can't sort out my leaks... Gonna give that one more "throw new parts at it" attempt with a reman pump and hope that takes care of things. Beyond that though, I like the idea of electric steering, even if I've always heard that hydraulic gives better feel. I don't drive many modern cars to compare. I like the idea of it never leaking though!
 

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Discussion Starter #14
Also, I had no idea that the MR-S had electric steering. I was considering picking up a Prius setup if I can't sort out my leaks... Gonna give that one more "throw new parts at it" attempt with a reman pump and hope that takes care of things. Beyond that though, I like the idea of electric steering, even if I've always heard that hydraulic gives better feel. I don't drive many modern cars to compare. I like the idea of it never leaking though!
it is actually good you brought that up,

the issue with electric steering is not the system itself but the developers doing the program.

as an example

the BMW M3cars (forgot since when) have electric steering.

the issue is that BMW programmed the steering to have assist on the return to center portion which is what ALL the complaints about numb feel was. It wasn't the turn in feel.

Funny enough all those parameters (to include bump steer, assist rate at center and at turn, assist based on speed) CAN be programmed. The ATS also have electric steering and they actually disabled assist on the return to center portion. That is why the ATS felt better to the leagues of BMW M3 purist. Everyone asks why?

Because the system is programmed by a couple of folks and then that is what they go with.
 
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