New booster option for e30 - Bosch iBooster

[hoveringuy]

I just got to try it. Compared to my current brakes, it feels much smoother. No delay.
it feels like when you're riding a nice e-bike, it doesn't feel like the motor is helping but you just have a lot of wind at your back.
The true test will be if it feels uncommunicative or overboosted on the road

[nando]

Holy cow! FredK in da house!

To give some color to my discussion with hubcapboy - the N52 three stage manifold takes up a shit ton of room. Basically, if the Model S booster clears that by a finger width, it's going to clear pretty much everything else by a mile. IMO, it makes swaps of all kinds a much simpler and cheaper proposition.

I'm still not sure about the model 3 / honda booster. It probably clears a lot of typical swaps (certainly M5X). It could clear the S54. Clearing the N52 is a bigger hurdle.

[FredK]

Whoa, this is pretty cool! That test video of the guy in the Delorean was pretty convincing too!

[nando]

I'm pretty sure in reality it's no wider than the gen-1 booster. It's possibly shorter?

I have a line on a Honda booster for a song. I'm having a hard time not buying it on a whim.. there's a Model 3 MC for pretty cheap too. for a RHD booster, you're looking at least $500, plus the connectors. I feel like moving some bolts around at less than half that cost could be worth it?

Looking at it again, the ix is kind of oddball, everything is in a different position relative to the RWD E30. I think for sure, the Gen 1 will fit easily. I'm not certain about Gen 2. I think it's a "maybe".

[hubcapboy]

I want to say I found a RHD photo showing the part number and it was the same as the LHD... it might just be a casting number and it gets a part number when it gets cut one side or the other and assembled with a booster.

...a Tesla part number doesn’t do us much good because we can’t order from Tesla.

I think the model 3 (ibooster gen 2) would absolutely fit anywhere a normal booster would fit. The challenge I have with the n52 intake is extreme, and I don’t think it would fit with that constraint.

[nando]

Is there any technical documentation on the MC sizes?

If you dig through enough pictures, you'll see stampings of "25" on them.

[nando]

You know honestly, the flange isn't that much different on the Model-3 booster. It seems like it would be relatively trivial to move the bolt centerlines less than 3mm over:


I think the pictures are deceiving too. It looks like the connector sticks out to the side, but I think it goes pretty much straight down. Should easily fit within the huge envelope of the original E30 booster, no?

[nando]

It looks like the castings are identical, but the flanges are different (the CR-V's is thinner). However, it does unbolt from the main booster housing:

[kristov]

Is there any technical documentation on the MC sizes?

[nando]

Yeah, I saw that one yesterday, but it seems pretty crusty. Wish we could read the part numbers on it - I doubt it's very expensive new.

Really thinking about one of those CRV boosters though. Could always swap out to the Tesla RHD MC later on. What I like is I could get this put in long before doing a swap... keeping my E30 operable is one of the reasons I've been able to hang onto it through marriage and two kids. :p

[kristov]

https://www.ebay.co.uk/itm/Tesla-Model-S-70D-2016-Brake-Master-Cylinder-J121/383277652321?hash=item593d20d961:g:y9IAAOSw8Q5d1h2w

RHD MC if someone needs one.

[nando]

Another option could be the Honda CRV booster - it's a Gen 1 like the Model S. However, the MC has the ports on the wrong side, and the casting is single-purpose, so you can't drill them on the other side. It does come with a remote reservoir, and being a Honda part is pretty cheap if you can find one.

https://www.ebay.com/itm/46000-TLC-A05-2017-2018-17-18-Honda-CR-V-Power-Brake-Booster-Assembly/373144448405

[nando]

I took a chance on the Model S booster because it eyeballed to the right size. The Gen 2 booster from the model 3 does NOT have the same firewall pattern. Lars has that documented here:

https://www.evcreate.nl/installing-the-ibooster/

The master cylinder with the ports on "our" side from the Gen2/model 3 also will not fit the Gen 1. If you look at the ears, the two bolts between the master and booster are clocked 90 degrees when comparing the two. (ok... MAYBE it would fit, but the booster would be sideways which doesn't help fitment of the Gen1... it's taller than it is wide)

Lars figured out the RHD/LHD difference as well:

https://www.instagram.com/p/B1DXLYxIj3K/

We're definitely playing catch-up to him here.

I will happily take measurements from anywhere to anywhere. I think it would be useful to have a "silhouette" drawn of the two firewall bolts and the outline of the booster (to scale) so people can print it out to mock up.

Regarding the amount of work to tap for lines on the left... RHD masters are of course very scarce, but to avoid the seat problem and to avoid having adapters stickout out of adapters on the side of the master, facing, drilling, and tapping could make the unfinished side of the master suitable for a banjo bolt. As long as the master cylinder is rebuildable and you can get it apart, that's the kind of thing you can do with a drill press.

That delorean thread is exactly what I stumbled upon, and oudevolvo on that forum is Lars :)

ok, that's good to know, i was wondering if they were the same or not - they look similar enough, but it's hard to tell from pictures.

it's too bad because the MC is the same size and has the ports on the left instead of the right. Also, there's a Honda version of the same booster that you can get a lot cheaper because it doesn't have the Tesla name attached to it - of course, the ports are on the wrong side, but it is a 23mm MC.

It seems like a RHD Model S booster is about as plug and play as you can get for an E30, or just bend your lines around so they mount on the other side for the LHD MC, or do what Steve is suggesting.

there was also a flare connector somebody posted in one of those links that you could just put on the end of the E30 brake lines and thread it in - no adapter needed.

I figured these were the same people, but that one thread had everything in one place, while the others were spread out. I still think you could buy the connectors yourself for a lot less than $150 - although it does make it convenient to get it all in one package ready to go..

[LukeJ]

I disagree..

Just drill and tap for 3/8-24 and install an adapter to 4.75mm bubble flare.

Feel free to give it a try. Make sure you don't get any metal chips into the piston and cylinder during the process.

How deep should you drill to make sure you don't damage anything else?

Let me know how it turns out. ;-)

[hubcapboy]

I took a chance on the Model S booster because it eyeballed to the right size. The Gen 2 booster from the model 3 does NOT have the same firewall pattern. Lars has that documented here:

https://www.evcreate.nl/installing-the-ibooster/

The master cylinder with the ports on "our" side from the Gen2/model 3 also will not fit the Gen 1. If you look at the ears, the two bolts between the master and booster are clocked 90 degrees when comparing the two. (ok... MAYBE it would fit, but the booster would be sideways which doesn't help fitment of the Gen1... it's taller than it is wide)

Lars figured out the RHD/LHD difference as well:

https://www.instagram.com/p/B1DXLYxIj3K/

We're definitely playing catch-up to him here.

I will happily take measurements from anywhere to anywhere. I think it would be useful to have a "silhouette" drawn of the two firewall bolts and the outline of the booster (to scale) so people can print it out to mock up.

Regarding the amount of work to tap for lines on the left... RHD masters are of course very scarce, but to avoid the seat problem and to avoid having adapters stickout out of adapters on the side of the master, facing, drilling, and tapping could make the unfinished side of the master suitable for a banjo bolt. As long as the master cylinder is rebuildable and you can get it apart, that's the kind of thing you can do with a drill press.

That delorean thread is exactly what I stumbled upon, and oudevolvo on that forum is Lars :)