Kevin M

iTrader: (12)

I could feel the difference when I put my MRT one on. I'd pay the difference for the easier install, and mine is easier than 02-04s have it.

soggynoodles

iTrader: (50)

If I have SS brake lines and 4 pots and DBA roters, would it make a difference by installing this bracket?

RussB

iTrader: (2)

yes. the bracket keeps the firewall from flexing at the master cylinder.

soggynoodles

iTrader: (50)

So explain to me how firewall flexing makes your brakes mushy?

RussB

iTrader: (2)

can't, i have 3% battery left on my laptop

when you push on the brake pedal, it makes the master cylinder do stuff. the firewall is made of really thin metal (like tin foil) and flexes when the master cylinder is doing it's thang. the bracket stops that.

Nick Koan

iTrader: (3)

Its really something that is much easier to see then it is to explain. So, if you've got someone, pop your hood and take a look at the master cylinder while the other person presses on the brake pedal repeatedly. You will see the firewall flex near where the pedal connects to the master cylinder.

The bracket reinforces the master cylinder by bracing itself agains the sheet metal that surrounds your suspension/wheel.

Max Xevious

iTrader: (8)

it uses pixies and fairies to make it stronger !

soggynoodles

iTrader: (50)

Thanks for the info all!!

I know I'm not the only one with that question.

Egan

iTrader: (14)

What I found with the master cylinder bracket (from MRT) is that the entire resistance was being held back by the head of a bolt. Since the master cylinder does not necessarily move in a straight line towards the bolt and bracket assembly, some slippage occurs, rendering the bracket only somewhat effective. Think of it as the bracket pointing towards the master cylinder horizontally, but the master cylinder moving on an arc, towards the bracket and down. There just isn't enough surface area on the end of the bolt.

The real solution would be to have a fitting on the end of the bolt that completely fit around the end of the master cylinder, almost like a ball and socket connection. That would make the bracket much more effective. The Cusco bolt has a "washer" on the end which creates more surface area than the MRT one and may work better.

Maybe I will install my MRT bracket into the STi and try and fab up something for the end of the bolt.

Here's a pic of what I am talking about on the MRT bracket. I don't have the high res version on my laptop, so I'll look for it after work and zoom in on the bolt head. Hopefully this gives you an idea of what I'm talking about:

Wingless Wonder

iTrader: (7)

Additionally, another possible shortcoming of both the MRT and (I believe) the CUSCO bracket is that the gusset which spans the area from the strut tower side and the contact bolt side does not extend all the way to the front of the master cylinder in the area surrounding the contact point (bolt). This may allow unwanted flexing of the bracket itself. I think the gusset should be doing most of the work of resisting movement of the firewall/master cylinder, with the bracket itself just providing an attachment point for the gusset.

A steel gusset is stronger in tension than compression so the gusset must be on the 'inside' of the bracket (where current designs already place them). There's only so much space to work with in the area between the master cylinder and the strut tower so any bracket design is going to be a compromise.

--
0==WW==0
"…axles of evil…" - george w. bush

Egan

iTrader: (14)

True, and no matter how strong you make the bracket, the thin sheetmetal on the strut tower will bend as well.

bemani

iTrader: (5)

Cusco's JDM bracket mounts on the top of the strut tower, where you would mount the strut bar.

Obviously that won't work here since our master cylinder is on the wrong side.
This one seems like a hack?

Egan

iTrader: (14)

They need to make a LHD version of that thing!

Wingless Wonder

iTrader: (7)

Any add-on bracket is a hack. But, yeah, a top-mounted bracket would install in a reinforced area of the strut tower so as long as the rest of the bracket is triangulated sufficiently, it should resist movement better than the others.

What's on the other side of the strut tower? Just the strut and spring? Is there a way to install a small steel plate to distribute the load so the sheetmetal doesn't buckle? I'll have to take a look when the Cusco piece arrives.

--
0==WW==0
"…axles of evil…" - george w. bush

Egan

iTrader: (14)

Installfest! :banana: