New booster option for e30 - Bosch iBooster

[nando]

Hmm, it would seem the larger MC would be beneficial in that case to keep the pedal effort a little more normal?

I'll bet the failsafe mode assistance is programmable too. It's only a matter of time until that's hacked.

[jon volk]

Failsafe mode works as intended. Pedal effort is nearly zero, which take a few to get used to, but short controllable pedal travel from engagement to locked.

[nando]

neat - I'm thinking for myself, I'll be happy with just the default mode, but CAN control in the future could make things interesting. I like the idea of adaptive cruise control for example.

anyway, my i3 MC came. The bolt pattern is the same, and with a little nub ground off the back of it, it would fit right in. Of course, as noted the shaft is a little different - the i3 outside diameter measures at 15/16", the Model S at 1". They are nearly the same length - but the part where the rod pushes on it is deeper on the model S. I think it could work with some modifications, but first I'm going to look at disassembling the i3 MC to see if we could just drill holes on the model S MC. It only cost $30, so I'm not super worried about ruining it (although I hope I can keep it working!)

I'll post pictures of the differences later.

[hubcapboy]

New info on the CANBUS connections:

https://www.evcreate.nl/ibooster-can-bus/

[nando]

yeah, mine came with the connectors. Unfortunately they cut the pedal position sensor from the main plug, but it's still there.. I just have to reconnect the wires.

[hubcapboy]

BTW, the Honda Accord and CRV (that use iBoosters) come with a remote reservoir from the factory that will attach to the same style MC used on the Model S. I don't know if they'd work upside down, but they would certainly increase the clearance for different manifold setups.

oh that's pretty goofy... well spotted



For anyone trying to track down plugs, any of the dismantlers who have these parts listed are probably just unplugging them and scrapping the harnesses for copper. If you reach out directly to the dismantler and they specialize in these types of cars, chances are they have one that hasn't been taken apart yet, or a shell sitting in the yard with the harness intact. Don't confuse "not listed on ebay" with "not available" when it comes to factory plugs.

If you're asking, you'll need the large power and computer connector, the small pedal position sensor connector (which loops back into the large connector) and the float level sensor and switch. There's no penetration into the tank for the level switch... it's a reed switch that's operated through the reservoir from below.

[nando]

BTW, the Honda Accord and CRV (that use iBoosters) come with a remote reservoir from the factory that will attach to the same style MC used on the Model S. I don't know if they'd work upside down, but they would certainly increase the clearance for different manifold setups.

[nando]

Mine came with cut off fittings - I can take pics/measurements when I get a chance to disassemble it.

As fast as the MC - I'll have to find out. I got an i3 MC for the cost of a nice lunch, so if it doesn't work out, no big loss. It does however appear to be 23mm, so that would be awesome if it does work.

[hubcapboy]

The i3 and x3 masters looks like they have a smaller diameter "plug" on the interface into the booster. They certainly aren't the same shape (there's a side-shot of mine separated on the first page).

I haven't taken my pedal linkage apart or taken a good look at it. We're going to need to lengthen it, if anyone wants to take a look at how best to do that.

I'm also curious what the Tesla hard line flares look like if you unscrew one. I think they're M12 ISO double flares (not bubble flares). I ordered the wrong adapters the first time.

If I was stuck with a LHD master and didn't think I'd have room for the ports on the engine-side, I think I'd try attaching to the reservoir ports and mounting it upside down. This is a similar idea:



There shouldn't be any pressure there other than the head from the remote reservoirs, and as long as they're mounted above the master the cylinder won't know which way up it is.

This would put your outlets on the fender side and your reservoir connection on the bottom. It would actually give you *even more* room because the next closest interference if you're doing something crazy like ITB's is probably the reservoir tank. It would also open up your shopping options to any ibooster master with the right diameters, because the shape of the reservoir is no longer important.

You could even use the Chevrolet Bolt master, which is super goofy and at 45 deg rotation:

https://www.ebay.com/itm/2016-2017-CHEVROLET-VOLT-Master-Cylinder-84006919-OEM/124017747341?hash=item1ce008a58d:g:f0gAAOSwUORd~Q2b

(before you get too excited about that whole thing being $83 with the booster and everything... that one's different at the firewall, although it does suggest that sourcing a replacement "booster" out of the middle of your RHD assembly is going to be cheap going forward.

[nando]

RHD Model S booster in. Anything you folks wanted as far as measurements?

Looks clean, nice score on the RHD master cylinder. Mine will be here within the hour (LHD though). Can't wait to mess with it. :)

[nando]

The X3/X4 MC looks promising as well:

https://www.ebay.com/itm/2011-2015-BMW-X3-OEM-3-0L-BRAKE-MASTER-CYLINDER-W-RESERVOIR-TANK-34336794473/143761928740

I can get both an i3 *and* X3 MC for less than the cost of shipping a RHD Model S MC from Australia.. so I might just go for it. Brand new X3/X4 MCs are like $100, and I'll bet the Model S reservoir will fit. if it works you guys can thank me later :p

[Bored]

RHD Model S booster in. Anything you folks wanted as far as measurements?

[hubcapboy]

Tough to say without getting one in hand, but looking at the photos did make me think that threading the reservoir bungs and remote-mounting the reservoir could be an option... then you could just run the master cylinder inverted as well.

[nando]

I'm convinced that somewhere, there exists another MC that's not necessarily Tesla, fits the same bolt pattern as the gen 1 ibooster, and has a bore suitable to the E30 with the ports on the correct side.

For one, these kinds of parts don't get made in a vacuum. Tesla buys from suppliers like everyone else - suppliers who want to save as much capital on tooling and designs as possible.

So the same reason this bolts into the same firewall pattern as the E30 (and every BMW since the dawn of time, apparently), there must be more than one MC that bolts to the ibooster.

Anyway, just wasting time on a google image search, I think the i3 MC is a potential candidate - and, it's cheap. Thoughts? Part # 34336858911

https://ebay.us/DGb7Yh

[Trevbot]

It's far more hazardous to the safety of other road users to cobble together hydroboost systems from junkyard parts, use outright dangerous chase bays single circuit master cylinders, or build iffy looking unengineered remote booster setups, than it is to install a twin or tandem cylinder manual brake setup with more pedal travel which can still lock the brakes on dry pavement without undue effort.

This solution is not a hydroboost, has dual circuits, was engineered by bosch to mount directly to the firewall on an identical flange to the E30, and retains factory ABS. All the reasons you have listed are exactly why we are pursuing this.

Also, some things are not adequately protected from water intrusion in all orientations, something further to look into is to sure to make sure it is well sealed in the inverted position and shielded if it is not.

If you read the whole thread you would know it is used in the "inverted" orientation in a RHD model. Actually its on the first page.