So the rumor was that Honda spec'd a 1" Brake Master Cylinder for the 05-06 DC5-S... however I have not found any proof of this, and in fact I bought an 06' DC5-S BMC and it was 15/16 like the 01-04 DC5-S...

Can anyone disprove that a 1" BMC does not exist in USDM land?

It is said that the DC5-R in Japan has a 1" BMC, but I have not seen anyone say definitevly either. But a Right Hand Drive BMC is useless anyways because the hard lines flare fittings are on the wrong side so it's sort of a moot point.

I just want to know if the ITR Brembos are supposed to have 1". I have them, and best I could find in Left Hand Drive was 15/16, and Hopefully that will be a big improvement over the EP3 one which I thought was 7/8" or 3/4" I do not know what it is until I take it out...

Also is there any tuning necessary when swapping BMC + Brake Booster? In the helms it says you should adjust the throw or something with some Propietary honda parts, am I going to get bad performance if it's not spec'd correctly?

 

The Base RSX and EP3 I believe have a 3/4" BMC stock... and I have the DC5R Brembos...



So when increasing the caliper's piston displacement, the stock master cylinder now has to push more fluid, so it has a longer pedal throw... Larger Master Cylinder would equate to shorter pedal throw, and stiffer/more respensive.

I have a 15/16" waiting to go on in 2 days, I just was hoping to find out if a 1" exists in a Left Hand Drive version, if one did exist, I wouldn't put this 15/16" on. But since it seems that a 1" doesn't exist, people don't care, or whatever can't find one... Gonna go ahead with my 15/16" BMC install this weekend on my EP3.

 

Let me know when you're going to do the install, if you can do it Saturday, I'll stop by. I'll bring my DC5R MC to compare.

-Victor

 

Good deal! Did you get my email? I'll drop you a PM...

 

I heard about the install -- do tell! How is it now?

 

Yes, it was a bolt on install. With the DC5S 15/16" MC and a fresh fill, it felt a lot better. Now when I get some free time, I'm going to do the same thing for my DC5R Brembo swap. Bill will chime in about his thoughts soon.

-Victor

 

The whole process was easy, 2 hardlines, 1 vaccuum line, 1 codder pin, and some extraneous 10mm bolts to move... took about 3-4 hours? bleed the brakes really really well... I plan on bleeding them again in about a week since on one line I was still getting some tiny air bubbles. They have since become a tad mushier than what you felt Victor, but that's normal.

The brakes feel great, really wham down now when I stomp on them. I paid about 150$ for the 06 type-S Master Cylinder Used. you will need around 1.5 liters of fluid, good time to do the ATE 200 (Gold) or ATE Blue... http://www.car-parts.com is where I got mine.

The trick for EP3 and DC5 is that all Left Hand Drive master cylinders are interchangeable. If you have an EP3 you need to swap the external reservoir onto the DC5 master cylinder; 1 phillips screw and pop it off, easy cheesy. Any RHD (i.e. JDM or UKDM) master cylinders will NOT work as they have the hard lines on the wrong side. Bring an flare nut 10mm open wrench, it's the only way to do hydraulic lines...

As for the sizes... it's a mystery still. I have searched high and low, and heard conflicting and 2nd hand accounts. Honda released this press release

http://www.hondanews.com/CatID...ves=t

Standard 4-wheel disc brakes with a 3-channel Anti-lock Braking System (ABS) help to provide secure stopping power. The RSX is equipped with 10.3-inch ventilated discs in front and 10.2-inch discs at the rear. To match its additional performance capabilities, the RSX Type-S uses larger 11.8-inch ventilated discs up front. For 2005, a larger diameter master cylinder was applied to increase hydraulic pressure, the rigidity of the brake pedal increased and the pedal stroke was reduced. These enhancements combined to both enhance stopping power and improve braking feel.

But in 2006 they said:

Large disc brakes at each wheel help deliver exceptional stopping power. In front, the RSX uses 10.3-inch ventilated discs, while the high-performance Type-S features 11.8-inch ventilated discs. Both the RSX and the RSX Type-S are equipped with 10.2-inch rotors at the rear. The brake systems on both models have a low pedal stroke ratio, a rigid brake pedal and a large diameter master cylinder for enhanced performance and superior braking feel.

Point is, honda implied in a press release that they increased the master cylinder... you can interpret that however you want, but the important part to realize is that honda could NOT have increased the master cylinder from 2004 to 2005, because the statement is vague. I'm not going to get into the nitty gritty, there is a thread on club rsx where I duked it out already over that...

PLEASE... if you find a 1" master cylinder, take pictures for christ's sake! It says what size it is under the bottom!

Here are the 4 accounts of people who have claimed to have done this:

I bought a 2006 RSX-S master cylinder was 15/16"

Logan says he has seen or has a 1" master cylinder.

DC5ITR329 says he has a 1" like Logan.

Victor had an ITR Master cylinder, and it was 15/16"

Works great, the pedal distance has settled in, and I reccomend it to anyone...

 

Are you guys doing to do the brake proportioning valve, too? Or is that going to be necessary at all?

 

People have said it makes a difference, and I'm sure it would make sense, but only place I could find it was 100$... more than I paid for the full master cylinder!!! so... maybe should just get the type-S one... I've never seen one, and not sure where it goes... not in the helms at first glance, but can't be that hard to find, gotta be on a hardline somewhere.

The install is easy, the only hard part that you need to be careful about is the hard lines which if you cross thread or mess up can give you a leak, and then you have to replace the entire line, and that would be expensive and tricky to get it back in place. 10mm flare nut wrench is key:



Lemme know if you wanna do the install Leland, I'll give you a hand.

 

Cool -- maybe that'll be something for me to do along with camber kit parts.

It's funny -- after doing suspension, rims & wing, i/h/e, and a hub & brake swap, it's the little things that are interesting me, even though there's hardly any showoff-like glory in them.. lol

 

Oh, DUH...

I just realized that a friend of mine has an '06 Type-S.

Shouldn't I be able to look at the part and see its size?

 

LMK if you guys want to do the P Valve. I can get them for about $50 new. The P Valve is the same from 02-06 TYPE-S. The base is different. Once I get the TYPE-S MC, I'll do it all the same time.

-Victor

 

You are saying the type-S and the ITR have the same P-valve? If so, count me in. I'd probably be in if it was even just the type-S... better than the EP3/base one.

Logan is going to try and get me some pictures of his MC that says 16/16 on it. So definetly try and get the 05/06 ones... I may have had bad luck and gotten jipped at the used parts dealership, but need some hard proof to get some $ back or something...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ocelaris &raquo;</TD></TR><TR><TD CLASS="quote">You are saying the type-S and the ITR have the same P-valve? </TD></TR></TABLE>

No, sorry, I was just refering to the years of the TYPE-S. I'm going to do the TYPE-S either way.

-Victor

 

Ok, there was some confusion, but now it is settled...

There is no 1" Master Cylinder.

You can see the 05/06 DC5-S and DC5-R Cylinder which is 15/16 and the EP/base is 7/8

 

Good stuff, Ocelaris.

 

Sorry, those aren't my pictures, Logan took those pictures... but if you read the CRSX thread, I will take credit for that

 

Took a brief look at mine couldn't fine the stamped size though thanks to Ocelaris we already know I have a 7/8" BMC. Only thing I see I'd have to unbolt are the two bolts holding it to the drum looking thing and two valves. Looks pretty easy enough.

Please let me know how it works out for you Ocelaris, and the brake firmness improvement over the EP3 7/8" BMC. I've never really "driven" a Type S to get a feel for their brakes so I'm curious. I HAVE swapped to Type S calipers and rotors, might benefit from the larger BMC as well.

 

Don't forget the brake booster, you have to swap the brake booster and master cylinder together. You're right about the master cylinder, it's only 2 bolts, 2 hard lines. The brake booster has 4 bolts inside the cabin you have to remove and 1 codder pin. pretty self explanatory. Only difficult part is making sure the hard lines are not cross threading when you put them back in. Bring at least 1 liter of fluid to flush, and it was reccomended to me, to flush again once you have put the ABS into effect. So it's not a stretch of the imagination to get 2 liters of fluid to flush.

I thought I had said that everything has worked out great, but if I hadn't made that clear, everything works great! no problems, it's not like a super duper huge difference, but it's definetly in my book worth the 150$ I paid for the 15/16 BB + MC.

 

I thought I read in that other thread that a second flush wasn't necessary -- but that a second bleed was needed after invoking ABS. Would there be enough in a 1-liter can to bleed some more?

Also talked to Gary via IM earlier today. He was totally impressed; "Have you driven Bill's car yet? Holy jeezus.. stops on a ******' dime"

 

Probably want to get 2 liters just to be safe. I ran through 1.25 after the first flush. And wasn't totally satisfied with 1 of the lines. So 2 liters is probably best. then you can use the last 0.75 to do the second bleed after ABS was invoked. Normally I only use like .5 liter per flush, but to really get the air bubbles out, had to do it major time.