I am doing a DA rear disk swap and I have everything I need but the right prop valve. If I were to leave it on the stock valve until I find one would the car be safe to drive? I know that the proportions are different but what is the difference in the proportions between say an DX valve and an Si or DA valve?

Thanks

 

man i was about to post the same thread i just picked up civic ex rear brakes for my lx sedan so im in this with you lol i wanna find out aswell ill post if i find anything out!

 

there is no apparent rhyme or reason with the numbering of the proportioning valves. its NOT a ratio. so dont use a stupid / between the numbers.

that said, i recommend trying to find the brake SYSTEM that closely matches what you have. but, 4040 is known to work fine with just a rear disc swap.

http://www.norcalcrx.org/tyson/pics/brakepartslist.gif

i have a lot of 4040 for sale. $35 shipped.

 

Tyson, What valve comes standard on a DX, any idea? What car is the 4040 off of? I might actually be interested in that.

Also, I have a prelude MC for the swap, however, I couldn't find any place around here that carried the reservoir for it. Is the standard DX MC reservoir OK to use or do I actually need to have the extra fluid that the bigger Prelude/Integra reservoirs hold?

I know these are real newbie questions but I'm not mechanic I'm mostly just curious.

 

+1 ex si da does it matter what you have in the back what proportioning valve is best to use and one more thing how the heck do you even change this i know nothing about brakes systems lol but still wanna get this disk brake swap done and over with

 

sorry ef white dont wanna thread jack just wanna know how to do this two

 

im also doing the swap i just got the brake booster, mc,4040 prop valve out of a 91 teg.i was looking at my friends rex and noticed ther 2040 or 30 40 i dnt remeber,but i was reaserching and i read that if you just put the rear disk with out the bigger mc and bb your pedal will feel real spongy and mabe unsafe.and if you dont get the proportioning valve then youll never get the full force of the breaks.google is your friend

 

Naw man, you're good.

In fact I could probably answer that question for you.

The prop valve is on the passenger side of the engine bay, you'll see the brake lines coming in from the MC and then have some lines going out to the wheels. AFAIK it's just a direct bolt in replacement for the one that's already there it just has some difference to it (which I'm trying to figure out) that is needed for rear disks vs. rear drums.

 

wonder if i could just order a proportioning valve for a local auto parts store but for an 89 ef sedan whats better da one or si ex one i would think ex would be a better choice seeing how the ex had rear disk brakes and the ex si vavle be native to an ef sedan what do yo think

 

you don't have to change the prop valve from what I have seen the si crx's came with a 1720 and they had rear disc the hf crx's didn't and they came with a 1720 also your stock one in superior enough to do the job unless you upgrade the front BIG time its not needed to go to a 4040..... saying thins i have even seen that most of the 92-95 civics are the same way the ones with disc brakes using the same exact prop valve as the ones with drums if you wana do anything upgrade booster and master

 

i don't know how to do all that bro lol so from what your saying i can just bolt this all up and my STOCK LX valve will work i don't want it to lock up kill me on the highway lol so im just trying to figure this out

 

Oh, I'm not sure then.

From what I was told this part just replacing something that's already in line with the brake system. If there's more to it I'm not sure so take my word with a grain of salt I guess...

 

I have already done this swap on my Dx hatchback. Mine is an 88 so i had to not only get the rear discs but i had to take the struts and rear lcas if you have an 89-91 you dont need this. The Da rear brakes and the Si rear brakes are the same. I also used the Da e-brake cables. I changed my MC and Booster to the non abs Da one and left the proportioning valve alone, i had The Da one to change it but i couldnt get the lines off the old one and i didnt want to break them so i just left it. In my opinion the proportioning valve doesnt change much in the characteristics of the brakeing. My car stops a lot better than it did before and better than my friends integra. It is safe to run the DX LX or SI civic prop valves I have been running mine for months with no problems. If you have anymore questions just ask.

 

Thanks for the input Projekt, I'll be putting it all together this next week while I'm off work for the holidays and I'll take it for a test drive around the local roads to make sure all is well before I go on the highway again or autocross it.

Next week I've got my work cut out for me too I've replaced every bushing in the rear end. I got a set of Koni/GC suspension with a 350/280 setup and I broke something in the transmission right before I started this project so I've got another one I'm throwing in temporarily until I get the DOHC ZC swap set to go for this summer and I'm overhauling the interior (ripped up the carpet for replacement and replacing the seats and rear seat delete).

 

You're mistaken. The 90-91 Crx Si that came with rear discs has a different 2040 prop valve.

Ppl who have changed out their 1725 for a 4040 with rear discs have reported improved and proper braking.

 

Tyson, I also just noticed that link you posted, it didn't work on my phone when I posted before but OMG thank you so much for that I'm saving that in my car docs folder

Also, any idea about the MC reservoir? I have a Prelude MC that I'm going to use since I was unable to find any place that carried the DA MC unit and the only prelude one I could get a hold of didn't have a reservoir on it. I have the DX reservoir for my old MC I can use if that one will work or I can go hit up the junk yard this week to see if there is an EX/DA/Prelude sitting in the lot that I can grab one off if I need the larger reservoir.

 

ef ex are 3540... i just swapped by buddies out for a 4040 just because we had an extra one. lol

i don't think it made any difference at all but oh well.
i have that 3540 in the garage $15 shipped for those who are desperate... lol

 

sorry haven't seen a 2040 on a ef at the yard just going by what I see most are 1725 my crx has a 1725 right now i have a 4040 i just got at the yard the other day just haven't got to put it on yet since its been 17degrees outside lol

 

noob speaking out here you guys are losing me i have the full hubs trailing arms rotors off of an already brake swapped 91 ef hatch that's all going on to my 89 ed sedan now the proportioning valve that's 40-40 is the out i need??? im so lost how can you tell could i pop my hood and see what mine is where on the master cylinder is it sorry this was the only concept of this whole swap im confused about i apologize in advance

 

I took the 2530 out of my hatch and installed a 4040. I also installed the larger bore m/c out of a 90 EX sedan. If you look on the front you can see where the prop valve is stamped.

 

hmmm i am not aware of a 2530. what kind and year of hatch?

 

It's an 89 Si. A USDM made in Canada if that makes a difference. I've had it since 98 and I'm the second owner, I knew the previous owner and am 100% sure she didn't make any changes. She was annoyed when I put my MOMO steering wheel in it.

 

ok ill look into it. i did notice today i never cross referenced 3dr hatches. mostly cuz i dont care bout them, lol.

 

nice price

wrong. I have full DC brakes on my EF with stock Std MC and booster, works fine.

Wrong. proportioning valve will not reduce braking force. Just the proportioning thereof

You will be fine for 99% of the time. You SHOULD use a prop valve from a 4wheel disc car though. Even better if it is for a setup that closely mirrors your own.
Prop valve is stupid easy to swap. Buy one from Tyson and git r dun

 

so tyson would you sell me your 40 40 proportioning valve? if so how mutch?