The JDM DC5R Brembo conversion thread !

[npcan2]

So I've done some researching, and with the help of my mates here at Honda Australia and in the UK I have hard information on the braking system in the DC5R.
TL;DR
- If you're upgrading to JDM Brembo calipers, you will need to change your proportioning valve to any JDM 01-06 DC5R unit (found in USDM 03-07 accord and USDM 03-05 civic si) or you'll ruin your braking performance by always locking the rear brakes first.
- If you don't want mushy brakes, change the brake booster as well to JDM 01-03 DC5R Unit.
- But for ultimate brake feel and performance, there were revisions made to the facelift JDM DC5R 04-06 Brake Booster and Master Cylinder for even greater brake feel, whilst the proportioning valve stayed the same.

Part Numbers directly from Honda

Brake Booster:
01-03 AUDM DC5R: 01469-S6M-Q50
01-03 JDM DC5R: 01469-S6M-J50
04-06 JDM DC5R: 01469-S6M-J80

Master Cylinder:
01-03 AUDM DC5R: 46100-S6M-J52
01-03 JDM DC5R: 46100-S6M-J52
04-06 JDM DC5R: 46100-S6M-J53

Proportioning Valve:
01-03 AUDM DC5R: 46210-S5A-822
01-03 JDM DC5R: 46210-S5A-812
04-06 JDM DC5R: 46210-S5A-812

Hope this help anyone else doing the conversion

[Flippit]

I've done the conversion and taken it to wakefield and the rear brakes never locked up on me? I must say though they do feel a bit mushy but I have not changed my rear pads yet so will see if that changes after. Good info though mate definitely something to look into for future!

[npcan2]

I've done the conversion and taken it to wakefield and the rear brakes never locked up on me? I must say though they do feel a bit mushy but I have not changed my rear pads yet so will see if that changes after. Good info though mate definitely something to look into for future!

I found the rear end twitchy under heavy braking at Phillip Island, so that's where I got 'locking the rear first'.
Also, the amount of times i've bled my brakes trying to get rid of that mushy feeling... it makes since that more fluid needs to go to the front given there is 4 pistons instead of 2.

[Flippit]

I found the rear end twitchy under heavy braking at Phillip Island, so that's where I got 'locking the rear first'.
Also, the amount of times i've bled my brakes trying to get rid of that mushy feeling... it makes since that more fluid needs to go to the front given there is 4 pistons instead of 2.

I wonder what the differences physically are though?

Because, If the booster was too small or was not holding much vacuum the pedal would feel hard and car would feel like brakes are dragging on, and come to think of it but quite possibly the JDM is different to AUDM due to different atmospheric pressures in the world which effects air and volume and so on.

Just a thought ?

[npcan2]

I wonder what the differences physically are though?

Because, If the booster was too small or was not holding much vacuum the pedal would feel hard and car would feel like brakes are dragging on, and come to think of it but quite possibly the JDM is different to AUDM due to different atmospheric pressures in the world which effects air and volume and so on.

Just a thought ?

I'm not sure of the physical differences, but I found this regarding the changes to the facelift DC5R:
"Improvement of brake pedal rigidity by (rise of master cylinder diameter and rigid rise etc of the pedal bracket), actualizing the brake quality where the control characteristic which is effective securely even with little foot pressure is good. "

Not sure if it's the most reliable source though...

[Flippit]

Hmm so the actual pedal it self has been raised/moved too has it? Thats interesting! Are you going to go ahead with the JDM facelift booster and stuff? If so then let me know how it goes and if you feel difference.

[npcan2]

Ok,
So after a long time researching parts and sourcing parts, I finally had a 2006 JDM DC5R Brake Booster, Master Cylinder and Prop Valve installed. While I was there I also installed a Tegiwa Brake Master Cylinder Stopper (http://www.tegiwaimports.com/tegiwa-...egra-dc5-3192/)
Firstly, my mechanic told me the install was an absolute pig. Getting the booster and Master Cylinder out was apparently a real pain. Prop valve seemed easy.

Review:
Brake feel is softer than I expected. The booster and master cylinder makes the brakes much easier to press, so for daily driving they are quite soft. But as soon as you're driving hard and want to brake hard or heel-toe, they feel really responsive and have really strong feel. Honda have done a really good job designing brakes that work when driving slow or hard.

The prop valve has made the biggest difference to the braking performance of the car. No longer does the car break out at the rear under heavy braking. No longer does that car feel heavy to pull up; like a truck. The car brakes hard from any speed and doesn't ever feel unstable. Ever since I put the brembo's on the car, i found the braking either the same or worse than stock. Now I understand why honda put brembo's on the car. I can't wait to try them at the track.

Tegiwa Master Cylinder Stopper:
The unit looks good and is a smart design and would stop the master cylinder moving when hard on the brakes. I can't really review the performance as I got all this stuff installed at the same time. It can't do any harm and stoppers like these have been proven in other cars before.

Conclusion:
Brake master cyliner and brake booster make the car easy to drive at normal speed and gives really good feel and response when driving hard. Install seems to be complicated and price of brand new units from Honda UK come close to $1,000AUD. If you can find a cheap second hand set (as I did), I would do it. However there wasn't a huge difference and obviously will not affect braking distance.

The prop valve is a MUST for anyone with JDM Brembo's on their AUDM DC5. Honda designed our braking system around the 2pot front calipers not the bigger 4 pot brembo's. By upgrading the prop valve, your car will brake with the correct amount of front/rear bias for optimum braking performance as Honda designed it. Without the prop valve, the stock brakes out perform the Brembo's on the street and track. The prop valve is also very cheap new or second hand and can be sourced relativly easily and is very easy to install!

[Flippit]

Awesome stuff mate! May look into getting the P-Valve (46210-S5A-812) from Honda

[npcan2]

You won't be able to get it from Honda Australia.
Give Collins Honda a call in the UK (I used skype), and speak to Matthew Buckton from spare parts or try emailing him at MatthewBuckton@collinshonda.com. He can get all JDM parts and he is willing to ship to Aus. Tell him you got his details from Nick in Melbourne.
If you need a JDM VIN, use DC52301006 or DC52306200. These are both JDM Facelift DC5R VIN's.

[Flippit]

You won't be able to get it from Honda Australia.
Give Collins Honda a call in the UK (I used skype), and speak to Matthew Buckton from spare parts or try emailing him at MatthewBuckton@collinshonda.com. He can get all JDM parts and he is willing to ship to Aus. Tell him you got his details from Nick in Melbourne.
If you need a JDM VIN, use DC52301006 or DC52306200. These are both JDM Facelift DC5R VIN's.

Legend!!

I know a guy who works for Honda Australia, I'll see if he can pull any sort of strings, if not, Matthew it is !

[butter]

Bump from the archives.

I now own Chi's old DC5R with the JDM suspension/brake conversion, and today I tried to install DC5R AUDM stock suspension but it wouldn't fit.

I wasn't sure if there was a difference between AUDM stock suspension and JDM stock suspension. I'm hoping this post brings more light to this topic, as there is little documented on JDM stock suspension compared to AUDM.

The rear part of the strut would not line up with the same angle as the trailing arm. The angle was off about 20* from the slot. I'm stumped with why it wouldn't fit.
Neither the rear right or left would line up with the angle only being slightly off. I could possibly shave down the metal bushing to fit it, however I'm under the impression it should fit like a glove being OEM suspension.

Does anyone have any info? Or from this, I can conclude JDM conversions will need JDM stock suspension?