New booster option for e30 - Bosch iBooster

[e30mclow]

I'm going through a nut and bolt rework of my car at the moment. Given that I played with the iBooster location this week, I figured I'd throw some details up here.
This is a copy & paste from another thread, so excuse the somewhat irrelevant context of the engine position comments. Engine is a 1.5JZ and trans is a Nissan CD009.

Start Paste:

I'm recently back at it and decided that "while I'm at it", I'll try to get the engine and trans back another 1-1.5".

My limiting factors are two things

1. The engine mounts that I bought years ago aren't great. The passenger side mount was at maximum extension on the mounting slot, meaning it dictated how far back the engine sat (or didn't). Oddly, the driver side still had another inch of adjustment, you just couldn't do it due to the passenger side.

2. The iBooster is tiiiiight. I had to shave both it and the intake manifold where the engine already sat, let alone before sitting it back further. The proximity also meant the intake manifold needed to come off to get the engine in/out. Painful.

A hair is all that was in it..


So to do anything about issue #1, the booster had to move. I decided on 1/2" over and 1" down. This is for no other reason than it would seem to work and not move things too far from the brake pedal.
Feeling very fancy, I made and printed a 3d template to ensure everything would line up between the booster, the firewall, and the pedal box once all is said and done.

The three studs locate the new holes/template via the existing mounting holes, which are to be welded closed later.




After first modifying the pedal box by filling the pushrod hole and extending the mounting plate to take the new bolt locations, I welded the firewall closed.






Then I printed a plug that snapped into the template to give me an accurate hub-centric guide for where the booster protrudes into the firewall. Ignore the messy print as the plug and template are sacrificial and get drilled through. I then drilled through the pedal box and firewall in one, avoiding potential misalignment.






With that it bolted up perfectly in its relocated home, awaiting modification of the pedal (easy).
I don't know how I'll bend the lines tight enough but that is a problem for later.



..and with the engine back in, perfect!


Next is the mounts. Here is how far off of the firewall I was previously limited


Not bad, but it'd be nice to free up space at the front of the engine for what will hopefully be air conditioning.
I previously used hockey pucks as engine mounts and they served me very well @ $2 each, but the engine needs to come up 1/4" to get the sump over the steering rack. I've decided to use upgraded standard e30 mounts, which I of course didn't have yet, so....like a broken record I 3d printed some for mockup (they aren't load bearing as the engine is supported in place from above.

What follows is a hybrid mix of technology and cardboard aided design.

Mount and a baseplate for the soon to be 1/4" steel bracket.


Plate for the block.


In the absence of brains, cardboard trimmed to fit the gap between the two..


Then copied into 3D


That all then gets scribed with confidence/accuracy onto the steel which arrives in a few days. I'll add a buttress of course, but those are the crucial dimensions hopefully sorted. Once welded up I'll cut any unnecessary fat off of the brackets with the plasma cutter.

Hopefully once everything settles on the mounts, and I've modified the gearbox mount, it'll rest here compared to the starting point.

[Striker01]

Amazing write-up, I'll probably revisit this thread myself before long!
I dealt with T7 design in the past and found him quite good - maybe contact him to fix/advise?

It cost about what the adapter was to ship it to the US from the UK. I don't think I'll bother with trying to get a replacement as long as the AN seals are working.

Some of the stock reservoirs from that site may work, I only tried a few. Most don't come with a clutch output though. Having the reservoir remote mounted makes intake removal much easier, it's a tight fit as is.

[marcexec]

Amazing write-up, I'll probably revisit this thread myself before long!
I dealt with T7 design in the past and found him quite good - maybe contact him to fix/advise?

I actually created this account to drop a link to a new comparison page on the OI Wiki: https://openinverter.org/wiki/Bosch_iBooster - it has multiple types listed that might need less adaptation. If you have measurements to add, that would be awesome, too!

[Striker01]

I took the floating hall effect switch from one of the reservoirs (it works fine through 1/16" aluminum plate) I tried and mounted it upside down, to make it normally open, like stock E30. The float itself was tricky, had to figure out a way to install it after welding, that's why the cap is so big. The reservoir is baffled to mimic the stock E30 reservoir and I used AN6 bungs for the master cylinder and a 1/4" barb for the clutch.







The amazon AN fittings/T7 design adapter leaked, I tried to different brands from amazon so I think it may be the adapter. I ended up ordering some AN seals from summit and they seemed to have solved that issue.

[Striker01]

Couldn't find a suitable MC reservoir I was happy with so made one of my own.

I found a UK company that sells a Tesla booster adapter with AN6 fittings.





Made a mounting bracket out of some aluminum I had laying around. The forward facing bolts are very difficult to get to with everything in place, the threaded bracket made life much easier.



I ordered an aluminum weld in cap from Dedicated Motorsports and found a cap gasket on amazon: https://www.amazon.com/dp/B0CJP55D4C...fed_asin_title
Drilled a small hole in the cap to allow it to vent.

I didn't like any of the Tilton options because they vent direct to atmosphere without a gasket.

[bimmerreign]

Forgot to mention I also have LS3 headers if that matters to anyone. After eyeing some more today, it seems pretty unlikely it will fit even moving the mount over 1-2 inches. I'd have to clock it and make an adapter plate. I think I'll just end up going boosterless due to the tight fitment of everything with the LS and not wanting to custom fab a pushrod setup or big relocation plate. Can definitely see this working great for a different swap or someone who wants to fab something.

[bimmerreign]

Been following this for awhile and to help people in the future I figured I'd share my experience. I have an LS with Pennsyltucky V3 engine mounts. I bought a RHD ibooster from England in the hopes to keep power brakes with minimal modifications. However, I just put the engine in last weekend and there's interference with it, I tried every way I could to get it to fit but no success. I'm going to try and relocate the holes on the firewall like the racegerman template and see how that ends up fitting. I'll try to update on here afterwards.

[hoveringuy]

Up next, I'll be installing MK60 ABS and will have both it and the iBooster with on/off switches depending on what sort of driving I'm doing.

I run the Mk60E5 (E90, I highly recommend it over the E46 Mk60...)

It's like a superpower. Amazing....

I have a thread in the track section on it.

[jbontke]

Some notes to add after a few weeks of driving.

Up next, I'll be installing MK60 ABS and will have both it and the iBooster with on/off switches depending on what sort of driving I'm doing.

I have been looking at the MK60e5 ABS for a hot minute. What is your current brake setup?

[e30mclow]

Some notes to add after a few weeks of driving.

Without any means to control pedal feel in failsafe mode, I decided to manipulate the pedal outside of the iBooster.
I replaced the weak brake pedal return spring with a heavier duty item off of Amazon. I needed to shorten it slightly to add some preload/tension.



It works great and gives an improved pedal feel given the drastic assistance of the iBooster.
I then decided to see how the brakes feel while drifting. I like to sometimes left foot brake while sideways. It wasn't great.
Manual brakes offered far more controllable feedback through my uncalibrated left leg. I found that slight dabs on the pedal with my left foot now caused the fronts to lock, so I'll need to play with bias more.


Up next, I'll be installing MK60 ABS and will have both it and the iBooster with on/off switches depending on what sort of driving I'm doing.

[Striker01]

The X1 reservoir arrived. It will work but still not ideal, the search continues for a suitable MC mounted reservoir. The X1 firewall must tilt aft because with the ibooster in an E30 the reservoir is pointed down.



I was hoping to use the built in hall effect fluid sensor but it is normally closed where the E30 one is normally open, so iI had to shorten the E30 plunger so it will work correctly.



I also needed to extend the plug.



This one just clears the N52 intake tube, after some heat and a little massage, there was no hope as it was.

[Striker01]

Another question, what brake line adapters are you using? I was considering this one as linked earlier in the thread but I read that since the Tesla uses 6mm brake lines the flare on that adapter might be too small.

I found some m12 x 1.0 to 3/16 line fittings. The MC uses inverted flares.

Your order details

We'll let you know when your order has shipped.

6-Metric Brake-Pipe Fittings Unions Master Cylinder 12mm X 1mm Metric 3/16 Pipe


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[hp13]

Another question, what brake line adapters are you using? I was considering this one as linked earlier in the thread but I read that since the Tesla uses 6mm brake lines the flare on that adapter might be too small.

[Striker01]

I used the 2002 reservoir with e30 clutch elbows friction fit into the donor reservoir bottom piece. I wouldn’t recommend this rout, brake fluid is seeping around the fittings. I have a later model reservoir from an f48 X1 on the way to try, it has the clutch feed. I’ll post a pic once it’s installed. I’m pretty sure the intake manifold studs will have to be switched to bolts for it to work.

[jbontke]

What did y'all do to set up the line going to the clutch master cylinder? I'd like to use the original brake fluid reservoir but there's no outlet to feed the clutch mc.

Since not all iBooster reservoirs have previsions for a clutch feed, you could use the 2002 remote reservoir. Or use a small independent reservoir for the clutch.