Bosch iBooster Brackets for 60/80 Series – Tested in Moab, Ready to Go

[smritte]

This type of a system has been on my bucket list for quite a while. I haven't done any research into the force multiplier of the Honda unit.

From what Ive read of testing 90lbs of input pressure gives 250psi line pressure when power is off. 1200psi when power is on.

Thank you for that. I have the stock booster numbers for comparison somewhere but cant seem to find them.
One part I want to address is pedal travel and firmness. With that in mind I was considering going to a slightly bigger MC bore which will reduce line pressure some but will also slightly decrease travel and firm up the pedal.

Brakes come down to generating heat and then shedding that heat. If this setup overwhelms a stock system it could be a problem.

Not saying it is a problem. Just be aware of it until data shows it’s not a concern.

Anyone who thinks I’m overly cautious go find the video of the Chevy K5 (?) on lions back. I honestly don’t know what failed but wouldn’t wish that on anyone.

One of my buddies was there when it happened. Yes it was an early carbureted K5. He had stated the vehicle ran poorly and the girl driving it stalled the engine then tried to ride the brake down. Once you loose engine vacuum, the booster only has 2-3 pumps of the pedal until the boost is used up. Big tires increase leverage on the brakes and well, if you watch the video you see what happened.

When stand alone electric boosters came around, I decided it was something I wanted to convert to. If done correctly you can have boost with the engine off.

Watching thread intently

 

[bski90]

I've been working with Bosch iBoosters for the greater part of my career (10+ year Chassis Development Engineer for EV companies). These are extremely robust and reliable units; I can likely answer any questions about these if people have them.

 

[ajordan1975]

Definitely interested! Ever since I cammed my LS my brakes don't hold well in 4low.

 

[Hornd]

This type of a system has been on my bucket list for quite a while. I haven't done any research into the force multiplier of the Honda unit.

Thank you for that. I have the stock booster numbers for comparison somewhere but cant seem to find them.
One part I want to address is pedal travel and firmness. With that in mind I was considering going to a slightly bigger MC bore which will reduce line pressure some but will also slightly decrease travel and firm up the pedal.


One of my buddies was there when it happened. Yes it was an early carbureted K5. He had stated the vehicle ran poorly and the girl driving it stalled the engine then tried to ride the brake down. Once you loose engine vacuum, the booster only has 2-3 pumps of the pedal until the boost is used up. Big tires increase leverage on the brakes and well, if you watch the video you see what happened.

When stand alone electric boosters came around, I decided it was something I wanted to convert to. If done correctly you can have boost with the engine off.

Watching thread intently

If the Fluid Boils at the Calipers does not matter what is Applying the Hydraulic Pressure- Lock up the Rears with the Cable (E Brake on these Sketchy at Best) and Say a Prayer. A Runaway Cruiser could Quickly become the Casket.

 

[smritte]

If the Fluid Boils at the Calipers does not matter what is Applying the Hydraulic Pressure

Absolutely true but, why is your fluid boiling? If your generating enough heat at low speeds to boil fluid, you need to step up to a higher boiling point or you don't change fluid. Any real road speed has air pulling heat away from the caliper.

To stop these vehicles requires a certain amount of force and friction. Increasing the booster force only means your not pushing as hard on the pedal. If your rotor/pad combo cant hold up to the heat you generate stopping and cause considerable fade, its time for an upgrade. As is is, by increasing the tire size and adding extra weight, we should be increasing rotor diameter.

Also, the only way your even slowing down using the park brake is if you have a drum rear brake. I have rear disk. The drum in hat park brake was never designed to do anything other than hold you still when parked.

 

[White Stripe]

I've been working with Bosch iBoosters for the greater part of my career (10+ year Chassis Development Engineer for EV companies). These are extremely robust and reliable units; I can likely answer any questions about these if people have them.

What kind of line pressure do they typically provide? I found 1200psi in my research.

 

[Marvelicious]

I'm not saying brake fade is impossible on an 80, but I never hear it mentioned whenever someone starts talking about hydroboost, which should share the same combination of increased clamping power on the same calipers and rotors. I just don't see brake fade from too much brake line pressure as a big issue on these, unless some of you are taking yours to the Nurburgring?

 

[NeverFinis]

I'm not saying brake fade is impossible on an 80, but I never hear it mentioned whenever someone starts talking about hydroboost, which should share the same combination of increased clamping power on the same calipers and rotors. I just don't see brake fade from too much brake line pressure as a big issue on these, unless some of you are taking yours to the Nurburgring?

You don't have to go to Nurburgring to experience brake fade...

I experienced brake fade coming down from Pikes Peak. Not the upper section, where I used mostly engine braking and 4wd low, but the lower section where I was more relying on brakes.

The brakes were smoking. Everything is brand new: New Calipers all around + Power Stop Rotors and Z36 Pads. (edited to add: brake fluid was also new) I don't recall the exact temp, but the front rotors were over 500°F.

Larger Rotors + More Clamping Force is on my todo, which is why I am following this topic.

 

[Saito]

Open to correction if I’m wrong, but most of the time the fluid “boils” because of the moisture content and older brake fluids are hygroscopic and attract moisture when exposed to the atmosphere. That’s where the fade comes from. So keep the fluid fresh and have less likelihood of having that issue IMO.

 

[ajordan1975]

You don't have to go to Nurburgring to experience brake fade...

I experienced brake fade coming down from Pikes Peak. Not the upper section, where I used mostly engine braking and 4wd low, but the lower section where I was more relying on brakes.

The brakes were smoking. Everything is brand new: New Calipers all around + Power Stop Rotors and Z36 Pads. (edited to add: brake fluid was also new) I don't recall the exact temp, but the front rotors were over 500°F.

Larger Rotors + More Clamping Force is on my todo, which is why I am following this topic.

View attachment 4148218

everyone experiences that when riding the brakes on Pikes Peak, even on the lower half after the "check point"...

 

[bski90]

What kind of line pressure do they typically provide? I found 1200psi in my research.

That is entirely determined by the foundational system, master cylinder size and stroke, caliper piston sizes, etc. All these do is provide electro-mechanical assistance/boost verse the vacuum assistance of the OEM booster. Line pressure will be EXACTLY the same as with the vacuum booster, however, you may achieve deeper stroke due to the motor's assistance (based on whatever tesla calibrated with bosch) and thus higher line pressures and more brake torque.

 

[Marvelicious]

You don't have to go to Nurburgring to experience brake fade...

I experienced brake fade coming down from Pikes Peak. Not the upper section, where I used mostly engine braking and 4wd low, but the lower section where I was more relying on brakes.

The brakes were smoking. Everything is brand new: New Calipers all around + Power Stop Rotors and Z36 Pads. (edited to add: brake fluid was also new) I don't recall the exact temp, but the front rotors were over 500°F.

Larger Rotors + More Clamping Force is on my todo, which is why I am following this topic.

View attachment 4148218

Okay, but you're discounting my mention of a notoriously difficult situation by mentioning an equally notoriously difficult situation. I'm sure we could come up with a few more, but it doesn't change the fact that it's pretty difficult to do.

New fluid or not, you don't mention what grade you're using. For what it's worth, if you're pushing your brakes to the point where fade is becoming an issue, it would also be worth being sure to go to DOT 5.1, which gets you around a 50f higher boiling point than DOT 4 and something like 80-100f over DOT 3. It doesn't seem to be as common on the shelves of the local O'Reilly or whatever, but it's not significantly more expensive.

Either way, my main point was that I don't see this as being functionally any different from a fade standpoint than hydroboost. Both raise brake line pressure, potentially much higher than vacuum boost, but everyone who has done it raves about hydroboost.

 

[npcrs32]

Interested in this for my 40, 60 and 80.

 

[NorthWA]

Interested for my 96 stock w/abs.

 

[Brindleboxer]

Spoke with Torfab and they are still not offering this setup yet as they are still testing. I do plan on going this route once it is available.

 

[ScotyDosentKnow]

Spoke with Torfab and they are still not offering this setup yet as they are still testing. I do plan on going this route once it is available.

Thanks for the update! I want to diesel swap an 80 series and this may be the route I end up going so hopefully they figure it out soon lol

 

[1973Guppie]

Interested for my trail 80. I have been looking to help the brakes out but don't have huge $$$ for big brake kits etc. I removed the ABS system awhile ago and that really helped with braking but I still want better, firmer brakes. So basically this just gives you a booster that does not need vacuum? Is the purpose of this to vastly increase braking OR is it just for trucks that don't want to rely on a vac source? Curious what % increase in braking one can expect from this mod?

 

[torfab]

A quick update on the Bosch iBooster brackets:

I finally received the first production batch and have started assembling hardware kits for fitment. The firewall-side brackets are complete and ready to go. The only remaining item is the master cylinder side, where I'm currently using a hand-made adapter pin. I'm working on getting that component finalized before releasing them for sale.

This is currently a small pre-production run, so I'll only have a handful available initially while I gauge demand and make sure everything is exactly how I want it before moving into larger production.

Pricing is still being finalized, but I'm targeting somewhere in the $250-$350 range. Once I have everything nailed down, I'll post ordering information and a link here.

Thanks to everyone who's expressed interest so far. It's exciting to finally have these in hand after a lot of testing and development.


For those who missed the original post, this is the same setup I installed on my 80 and tested in Moab. Combined with stock calipers, stock rotors, quality pads, stainless braided lines, and no ABS, it delivered the best braking performance I've ever had from the truck.

 

[Kodiak John]

A quick update on the Bosch iBooster brackets:

I finally received the first production batch and have started assembling hardware kits for fitment. The firewall-side brackets are complete and ready to go. The only remaining item is the master cylinder side, where I'm currently using a hand-made adapter pin. I'm working on getting that component finalized before releasing them for sale.

This is currently a small pre-production run, so I'll only have a handful available initially while I gauge demand and make sure everything is exactly how I want it before moving into larger production.

Pricing is still being finalized, but I'm targeting somewhere in the $250-$350 range. Once I have everything nailed down, I'll post ordering information and a link here.

Thanks to everyone who's expressed interest so far. It's exciting to finally have these in hand after a lot of testing and development.


For those who missed the original post, this is the same setup I installed on my 80 and tested in Moab. Combined with stock calipers, stock rotors, quality pads, stainless braided lines, and no ABS, it delivered the best braking performance I've ever had from the truck.

View attachment 4153142

View attachment 4153143

View attachment 4153144

Following. Thank you!

 

[BayArea80]

I'm definitely interested!