I have been working on an S52 swap for the last few months. as an alternative to using the standard modified e21/rabbit/944 booster that most everyone uses in their cars these days, i elected to go with an option that gives me more braking power. this info is also on a thread in the 24v swap section, but i was thinking more of you could take advantage of it here.
i know...you are probably asking why i would want to install this on my car. well...i ask you, why the hell not? i have already modified a rabbit booster that i am sure would work fine. i just want more braking power. i have hydroboost on my diesel f350 daily driver and i love the system. i expect i will love it just as much on my bimmer.
on the right side of this photo are the brakes i am using on the front of my car.
a few months back, i picked up the system from an old e24.
everything was fine and dandy until i installed the engine.
i think it would work out fine if the engine were something other than m/s5x. there is no way around the conflict with these parts. the good news is that i read a thread a while back that you can use the hydroboost system of a 7 series e23. this is what i found at the just yard this week. if you are going to add hydroboost to your e30 with a 24v swap, it is going to have to be the booster from the early 7 series. notice how about a third of the booster is actually inset behind the firewall. this will get you the relief you need to clear the throttle body. the e23 is at the top, the e24 is below.
also worth noting in the photo above: the upper booster has an extra fitting between the rear port and the pressure hose. this is a restriction for applications with abs brakes. there is a little orifice with approximately a 1/64" hole drilled through. if you have abs and you plan for them to work, you will need this part. it is listed in real oem and priced somewhere around 25 bucks from the stealership.
an added benefit to going with the hydraulic brake syst is that the diameter of the master cylinder is much larger than the one from the e30. e30 on the left, hydroboost mc on the right for comparison
here is a photo with the e23 booster installed. the intake boot and maf will pretty much fit with out conflict at this point. the rear orifice on the bottom of the intake boot has slight interference with the hydraulic line on the front of the master cylinder, but there won't be any issue connecting the hose.
i found a nice out the way place to mount the hydroboost reservoir. originally, i wanted to locate it on the driver side motor mounting bracket, but the top needs to be mounted above the brake booster. otherwise, the fluid could drain back and overflow.
the accumulator is going to be mounted below the booster on the driver side. i cut the mounting bracket off the e23 so it would be a little easiser to fabricate.
i went through the 20 or so power steering hoses that i have laying around in search of suitable ends for my project. using my angle grinder(with a thin cutting wheel), i ground off the metal swage collars and slid the ends out of the old hoses.
doing a little googling on line, i found http://www.discounthydraulichose.com they sell the R1 hydraulic hose needed for about a buck a foot. this is a 2500 psi hose. the working pressure of the system according to my bently manual is about 1400 psi max, so this hose will work nicely.
they also sell a crimp collar shell for about a buck each.
unfortunately, they don't sell banjo fittings. i talked to a salesman about it, but he said suitable suppliers are unavailable. i did a little searching and found a couple of aeroquip fittings in their catalog, but for most connections, you need some sort of elbow after the attachment. this is why i am reusing my old fittings. when the hydraulic parts arrive in the mail. i will just cut my hoses to length, assemble them and take them to my local hydraulic shop to get them crimped.
i have read a few threads on the forums with people complaining that the hydroboost system is unnecessarily complicated. i don't think so. you definitely have more hoses to run and you have to figure out how to locate the accumulator, but really, it isn't bad.
the reservoir has been mounted, it is a bit tight against the maf. i may move it a little later on.
here is a photo of the accumulator with the high pressure hose fittings mounted to it. that is the factory bracket from the e23 but turned upside down. on the hose fittings, i left part of the crimped collar where it attaches to the metal line because as you can see in the photo, those high pressure fittings don't have much of a barb on them. some of the newer fittings on the power steering pump don't have any barb at all. once i have the collars crimped on, i plan to put a couple of (tig) tack welds between this flange and the collar for good measure.
these are the fittings i came up with for the power steering rack and the ps pump
here is a photo of the e23 accumulator bracket with a notch ground out to fit the brace on the front strut tower. keep in mind that this will be welded to the frame up side down.
its a little hard to see in the crappy photo, but there is the up side down bracket welded low on the frame with the accumulator bolted on. the bracket is just below the bank of brake lines, just behind the motor mount bracket, and just in front of/and above the steering u-joint. the fuel lines and the carbon canister hose touch on the back side. there is about 2 or 3 inches of clearance to the master cylinder/hydro booster above(removed for clarity). the biggest reason for mounting it that low was that i felt i needed to stay away from the brake lines. i didn't want to weld on a bracket that had a cut out for those lines only to have the possibility of replacing one later.
i know...you are probably asking why i would want to install this on my car. well...i ask you, why the hell not? i have already modified a rabbit booster that i am sure would work fine. i just want more braking power. i have hydroboost on my diesel f350 daily driver and i love the system. i expect i will love it just as much on my bimmer.
on the right side of this photo are the brakes i am using on the front of my car.
a few months back, i picked up the system from an old e24.
everything was fine and dandy until i installed the engine.
i think it would work out fine if the engine were something other than m/s5x. there is no way around the conflict with these parts. the good news is that i read a thread a while back that you can use the hydroboost system of a 7 series e23. this is what i found at the just yard this week. if you are going to add hydroboost to your e30 with a 24v swap, it is going to have to be the booster from the early 7 series. notice how about a third of the booster is actually inset behind the firewall. this will get you the relief you need to clear the throttle body. the e23 is at the top, the e24 is below.
also worth noting in the photo above: the upper booster has an extra fitting between the rear port and the pressure hose. this is a restriction for applications with abs brakes. there is a little orifice with approximately a 1/64" hole drilled through. if you have abs and you plan for them to work, you will need this part. it is listed in real oem and priced somewhere around 25 bucks from the stealership.
an added benefit to going with the hydraulic brake syst is that the diameter of the master cylinder is much larger than the one from the e30. e30 on the left, hydroboost mc on the right for comparison
here is a photo with the e23 booster installed. the intake boot and maf will pretty much fit with out conflict at this point. the rear orifice on the bottom of the intake boot has slight interference with the hydraulic line on the front of the master cylinder, but there won't be any issue connecting the hose.
i found a nice out the way place to mount the hydroboost reservoir. originally, i wanted to locate it on the driver side motor mounting bracket, but the top needs to be mounted above the brake booster. otherwise, the fluid could drain back and overflow.
the accumulator is going to be mounted below the booster on the driver side. i cut the mounting bracket off the e23 so it would be a little easiser to fabricate.
i went through the 20 or so power steering hoses that i have laying around in search of suitable ends for my project. using my angle grinder(with a thin cutting wheel), i ground off the metal swage collars and slid the ends out of the old hoses.
doing a little googling on line, i found http://www.discounthydraulichose.com they sell the R1 hydraulic hose needed for about a buck a foot. this is a 2500 psi hose. the working pressure of the system according to my bently manual is about 1400 psi max, so this hose will work nicely.
they also sell a crimp collar shell for about a buck each.
unfortunately, they don't sell banjo fittings. i talked to a salesman about it, but he said suitable suppliers are unavailable. i did a little searching and found a couple of aeroquip fittings in their catalog, but for most connections, you need some sort of elbow after the attachment. this is why i am reusing my old fittings. when the hydraulic parts arrive in the mail. i will just cut my hoses to length, assemble them and take them to my local hydraulic shop to get them crimped.
i have read a few threads on the forums with people complaining that the hydroboost system is unnecessarily complicated. i don't think so. you definitely have more hoses to run and you have to figure out how to locate the accumulator, but really, it isn't bad.
the reservoir has been mounted, it is a bit tight against the maf. i may move it a little later on.
here is a photo of the accumulator with the high pressure hose fittings mounted to it. that is the factory bracket from the e23 but turned upside down. on the hose fittings, i left part of the crimped collar where it attaches to the metal line because as you can see in the photo, those high pressure fittings don't have much of a barb on them. some of the newer fittings on the power steering pump don't have any barb at all. once i have the collars crimped on, i plan to put a couple of (tig) tack welds between this flange and the collar for good measure.
these are the fittings i came up with for the power steering rack and the ps pump
here is a photo of the e23 accumulator bracket with a notch ground out to fit the brace on the front strut tower. keep in mind that this will be welded to the frame up side down.
its a little hard to see in the crappy photo, but there is the up side down bracket welded low on the frame with the accumulator bolted on. the bracket is just below the bank of brake lines, just behind the motor mount bracket, and just in front of/and above the steering u-joint. the fuel lines and the carbon canister hose touch on the back side. there is about 2 or 3 inches of clearance to the master cylinder/hydro booster above(removed for clarity). the biggest reason for mounting it that low was that i felt i needed to stay away from the brake lines. i didn't want to weld on a bracket that had a cut out for those lines only to have the possibility of replacing one later.
Comment