Hi all,

I've got an EF6 JDM crx. Stock brakes are 242mm front, drums rear, 13/16" Master cylinder and a proportioning valve which says 2030.

I'm fitting twin pot Legend calipers to the front with 282mm discs and leaving the drums on the back. I've had plenty of crx's with discs on the rear and drums are going to be better for what the car will be doing.


On a EF8 SiR non ABS you get 262mm front, discs on rear too, 15/16" MC and a 2040 valve for what it's worth. I have a valve from one of those too.


I've read a few threads here about people swapping brakes out and changing the proportioning valve. Would anyone have a reccommendation for my setup ?
Worth noting that I will also be using a 1" MC from an Integra typeR.

Does 2040 mean that the fronts get a pressure of 40 and the rears get a 20 or is it the other way around? (it makes more sense to me that way and the numbers being of some significance but not a specific unit of measure?)

I'd have thought that a 4040 would put too much bias to the rear of the car ?


When I checked my valves I noticed that the ports on the side also have markings. One on either end of the valve. You can see some pictures here: http://www.nominous.com/pics/proportion
I wondered if anyone knows what significance they have and if it's possible or worth doing a hybrid valve by mixing different ends from two differing valves ?

Reason I ask this is having read quite a few posts about proportioning on here one with Tyson's comments sticks out:
https://honda-tech.com/zerothread?id=1721473
unless you can decipher the meaning behind 1725, 3030, 3040 and 4040, then go right ahead and tell us. none of us have figured it out other than looking at trends, which in total arent consistent.

If you wouldn't mind taking a quick look at the proportion valve that you have and please post up what it came from and the numbers on it, I wonder if we've been looking at the wrong thing ?

EF6 JDM 1.5 2030 33 68
EF8 JDM SiR 2040 47 74


Anyway, hope someone can shed some light

 

ive yet to figure anything out.

the 2 digit numbers next to the circles are probably just casting numbers. telling the date and mold number.

im pretty certain, in order for the number to make any sense, it has to factor in more than just MC size, and brakes front and rear. vehicle weight and wheel base are probably in the calculation as well.

there is also an odd thing that when the rear brakes acheive a certain amount of pressure, it will RELEASE pressure. cant explain any more than that.

i dont know anyone thats figured it out. it doesnt simply mean a ratio. otherwise, 3030 would be the same as 4040, so why have both, on two different cars, on two totally different setups.

theres a diagram in this thread that somewhat looks accurate to the construction inside our prop valves. but the text and the conclusion do not make sense. https://honda-tech.com/zerothread?id=820354


so i dunno.


btw, the JDM/European prop valve numbers are not what you listed. at least not according to my source. but its not 4040 either. i have it somewhere recorded in a conversation at home. if you can verify by pictures, and parts numbers, then i would appreciate that.

meanhile, here's all the relevant brake info ive gathered so far.

http://www.norcalcrx.org/tyson/brakepartslist.xls

 

I totally agree with Tyson but would add;

I think the numbers are intended by Honda to drive us crazy!

Wes

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">
the 2 digit numbers next to the circles are probably just casting numbers. telling the date and mold number.
</TD></TR></TABLE>

Perhaps, but as you say who knows for sure.
It would seem odd that it is different on either end. Both those valves I showed were from 90 JDM cars.
I wondered if perhaps they were valve sizes internally. I'll grab another spare one and rip it apart a little more.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">btw, the JDM/European prop valve numbers are not what you listed. at least not according to my source. but its not 4040 either. i have it somewhere recorded in a conversation at home. if you can verify by pictures, and parts numbers, then i would appreciate that.
</TD></TR></TABLE>
Part numbers will be a little harder as I have no access to the JDM EPC only the UK and Euro one. I can certainly ask some other UK guys what is in their cars for each of the different varients and I might get luck with some guys from Holland.

I can however assure you that those pictures are of genuine JDM EF6 and EF8 valves. Both without ALB. The EF6 is my car and the EF8 I just broke for parts.
Being in the UK we tend to get JDM imports. I've had a few myself.

I'll ask some guys on the UK crx forum to give me the numbers from their valves to add to the list.

 

Think about using a 90-91 Civic Ex prop valve.
That car had big front brakes and rear drums.

Also, a DA with ABS has a 1 inch master cylinder and has the brake lines on the correct side for use on a CRX.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nominous &raquo;</TD></TR><TR><TD CLASS="quote">
I'll ask some guys on the UK crx forum to give me the numbers from their valves to add to the list.
</TD></TR></TABLE>

i've already asked. not much response.

http://board.hondacrx.co.uk/ph...light=

i asked SETI, he's also here on honda tech, he's in holland too i think. he said VT had 2525. not sure what year. which totally doesnt make sense either. because it has front 17CL-14VN calipers for 10.25" rotors and rear disc brakes too.




Modified by Tyson at 9:16 AM 10/24/2006

 

Yeah, total lack of response huh.
TBH I'm not getting much back from people either. Have some folks coming round on the weekend who wont have ABS but the D16A9.
In the UK ALL VTEC crx's got ABS.
The Dutch guys didn't for sure and got PAS instead.
I'll double check with Bas (SETI) as I need to email him to remind him on something else.

JohnnieChimpo: we never got a Civic EX unfortunately and very few DA6's make it over as they were all JDM the model was never released UKDM.

 

so after doing a bit more reading on proportioning valves, another function (as well as proportion front and rear brakes) it has is to "hold off" the front brakes so that the rears get to brake first, especially in rear drum application. apparently rear drums need more time to actuate than discs because the shoes are not in contact with drum as opposed to disc pads always dragging on the rotor. its a split second operation, but i can see where it would be beneficial. at least this is the case with some early domestic models. and i can see it not being as needed when theres rear discs instead of drums.

just thought id throw that in to chew on.