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What are the advantages/disadvantages of swapping proportioning valves?
All,
I am making this thread to discuss the benefits/drawbacks of different prop. valves at the track.
It seems that all discussion is centered around "I drove my Civic down the street with a 30/40 and then I switched to the 40/40, and I felt no difference."
Well, as most of you know, braking at the limits and on the street are two different things.
I am constantly working around my brake biasing at different tracks. Coming out of the chute into the carousel at Summit Point Main, my car likes to lock up. Into Turn 1 and off of the main straight at NJMP Thunderbolt, my car likes to lock up. Autocross is particularly bad, where I will lock up ANYWHERE if I use all of my brakes-- again, forcing me to modulate more carefully.
re: What are the advantages/disadvantages of swapping proportioning valves?
Id venture to say 75% of us use the Integra 40/40 prop valve with a 99-2000 SI MC.
Front brake set ups vary from Integra GSR, 99-00 SI.
Big brake set ups from wildwood, brembo etc.
Then there are the hybrids ITR and Legend front brake set ups.
There are plenty of Brake threads for you to become more knowledgeable on the various types used. Google using Honda-tech in the search string.
This topic has been rehashed since 1998, and since we all have the same types of cars not much has changed.
If you are locking up there could be a number of issues, calipers pads poor brake lines, and yeap including the DRIVER.
Use quality pads for what you are doing (track or autoX) front and rear, even if they are OEM in the rear. (wait those are probably made in china too lol.)
Slow changes and test!
re: What are the advantages/disadvantages of swapping proportioning valves?
When you mention that you're using the stock proportioning valve, then if the car originally came with drum brakes, and you upgraded to rear discs, then yes, get the 40/40 proportion valve installed, and then see how that works. When I look at my proportion valve, I really don't see any label to know that it is a 40/40 valve, but my race shop confirmed that it is.
On my car (2000 Civic hatch race car with B18C type R and running approx. 2500 lbs), my front brakes are Type R / Honda V6 calipers (Honda V6 and wagons used the same calipers as the type R) using 11" rotors, and discs are also at the rear. We eventually upgraded from a 13/16" master cylinder to a 1". I originally used Carbotech XP10 pads front and AX6 (autocross) in the rear. When I switched to a more aggressive front pad (Raybestos ST43), I started having the front brakes lock up easily, so I switched the rear pads to Carbotech XP8 pads, and that seemed to balance things out pretty well again.
Anyway, if your proportion valve is for rear drum brakes and you've upgraded to rear discs, then get the 40/40 valve installed and then see how everything feels.
PS - are the brake sliding pins in good shape and slide easily? I usually check and regrease them every time I change pads, but I recently changed to a higher temp grease, so maybe that will hold up better. - Jim
re: What are the advantages/disadvantages of swapping proportioning valves?
A completely different car but I just parted out my 90 HF crx and had a NSX caliper front upgrade with stock DA rears using HP+ pads up front and HPS in the rear. Was using the 40/40 with a 15/16s ex master cylinder and it was very easily to modulate on braking with no lock up issues. Not sure if it was my suspension set up or lack or a rear sway bar but on heavy braking it seems to like to step the rear end out coming into corners which could of been my alignment too. I liked it so I left it, just looks like that happened in your photo too
re: What are the advantages/disadvantages of swapping proportioning valves?
A few questions (or points to think about):
1- What tires are you running?
2- Are you running optimal pressures, and have you tried playing around with the front/rear tire pressure distribution? (from your other posts, I assume you probably have, but sometimes we forget )
3- What is your alignment like in the front?
4- How old is your master cylinder?
You can always try to put more aggressive pads in the rear to simulate the effect a 4040 prop valve would have. What it will really do is apply more pressure at the rear, so you will have more rear bias. I guess the question here is: "What are you trying to fix?" Are you getting too much dive? One thing I have learned over the years is that the rears I run (rear EH Si calipers) tend to stop doing any useful work for me when they are approximately 1/2 worn, so my personal rule of thumb is to change the pads when they appear to be half worn.
From your picture, it seems like your fronts are locking up and not your rears, so you can probably get away with a little more rear bias. However, a lot of how you setup your car comes down to tire & suspension setup, weight distribution, and driver preference.
re: What are the advantages/disadvantages of swapping proportioning valves?
I was having a similar issue on my ek hatch. I found that integra front brakes have a larger piston than the civic with the same size brakes. I swapped to the civic front caliper and was very satisfied with the results. I did have to change to an integra brake booster after doing this as well as I couldn't generate enough pedal pressure to lock the tires. The integra booster provides quite a bit more assist which was needed with my 1" integra master cylinder.
re: What are the advantages/disadvantages of swapping proportioning valves?
I have been thinking this through over lunch, and something about these pictures tells me that you perhaps also need to adjust the driver .
You appear to be violating the laws of the traction circle in this picture, causing understeer by asking your car to turn (even just a little) and make use of 100% or more of it's capacity to brake. This causes your fronts to be overloaded and they just light up.
When you get into this situation, you normally need to ease off the brakes and remove steering input. This is totally counter-intuitive, as you are removing steering input to make your car turn more, put it will definitely help point your car in the correct direction.
You also appear to be looking at where the car is going, rather than where you would want it to go. Keeping your eyes on the objective/target does wonders in keeping the car off the grass.
Once again, I don't mean to criticize, but these are things that may help (and they don't cost a lot of money to try out and implement).
Not saying here that you don't need to adjust bias (see my other post above), but it is one thing to consider.
re: What are the advantages/disadvantages of swapping proportioning valves?
Originally Posted by Matt_EH3
I have been thinking this through over lunch, and something about these pictures tells me that you perhaps also need to adjust the driver .
You appear to be violating the laws of the traction circle in this picture, causing understeer by asking your car to turn (even just a little) and make use of 100% or more of it's capacity to brake. This causes your fronts to be overloaded and they just light up.
When you get into this situation, you normally need to ease off the brakes and remove steering input. This is totally counter-intuitive, as you are removing steering input to make your car turn more, put it will definitely help point your car in the correct direction.
You also appear to be looking at where the car is going, rather than where you would want it to go. Keeping your eyes on the objective/target does wonders in keeping the car off the grass.
Once again, I don't mean to criticize, but these are things that may help (and they don't cost a lot of money to try out and implement).
Not saying here that you don't need to adjust bias (see my other post above), but it is one thing to consider.
On point. Randy Pobst recently did a braking how to for Motor Trend on youtube. Might want to check it out.
re: What are the advantages/disadvantages of swapping proportioning valves?
I guess I made this thread to see what everyone was running in terms of brake setup and what prop. valves they were running. I made it "track experience only," because, these threads exist everywhere-- but the sentiment is generally "my car drove great."
I'm running a brake setup that mimics a popular choice among H2 Honda Challenge Drivers. This includes my rear pads.
The problem I have is, I've never been told whether I needed to or would ideally want to swap to a different prop valve.
I would consider running a different rear pad-- I have considered it. If I can save money on rear pads by just upgrading the prop. valve, I'd rather do that.
The picture is just for attention. I normally don't turn and mash my brakes at the same time
re: What are the advantages/disadvantages of swapping proportioning valves?
Originally Posted by Dilbones
The problem I have is, I've never been told whether I needed to or would ideally want to swap to a different prop valve.
Originally Posted by Calif_Kid
Anyway, if your proportion valve is for rear drum brakes and you've upgraded to rear discs, then get the 40/40 valve installed and then see how everything feels.
Originally Posted by .Grimace
Was using the 40/40 with a 15/16s ex master cylinder and it was very easily to modulate on braking with no lock up issues.
But the car isn't ready yet so I can't say whether it works well or not. But I'll tell you I don't understand any of this 40/40 business... I deal with part numbers and have yet to understand what part number this mythical prop valve is supposed to have.
re: What are the advantages/disadvantages of swapping proportioning valves?
I decided to take a quick look at part numbers, and for a 2000 Civic Si (that has rear disc brakes), Honda Automotive Parts gives part number 46210-S04-902 as the proportioning valve. The strange thing to me, is that they list the same prop valve for 2dr DX, EX, HX and also for 3dr CX and DX with all of those using rear drums per the website. The 2dr EX (with rear drums) calls for prop valve 46210-S04-962, and I'm not sure why it calls for a different part. The 4dr DX and LX (rear drums) also use a different part number 46210-S04-912, but I guess that maybe the weight distribution is slightly different.
There is also a brake upgrade thread in the sticky section of the Brake & Suspension forum at https://honda-tech.com/forums/suspen...egras-3044628/ and around 30% of the way down the thread, there is a short section on 'Brake Bias - Proportioning Valve'.
I looked up the above part numbers for year 2000 as I had heard that a 99-00 Si has rear discs so figured that its rear prop valve would be setup for rear discs, but if the part numbers and info on the website are correct, then it looks like the same prop valve was also used for some rear drum brake equipped cars. I wasn't sure what prop valve part numbers fit a 1993 Civic though, but I looked at the Honda Civic/Del Sol (1992-2000) forum and found some threads that have info on a 4040 prop valve:
re: What are the advantages/disadvantages of swapping proportioning valves?
Calif_kid, so according to the parts catalogs, the disc-equipped EKs use the same part number as drum-equipped ones. Just like what I found to be the case for EGs. My research is just above your post. I can't believe Honda would make a serious mistake like this, not on two separate generation cars!
I also have an EK, but it has ABS so no issues there.
BTW, the different valve on the 2DR EX EK you mention might be due to 262mm front brakes?
So 262mm front /240 mm disc brakes use the same prop valve as 240mm front/drum rear. 262mm front/drum rear use a different one.
Last edited by KoRn_vIRuZ; 08-03-2016 at 04:46 PM.
re: What are the advantages/disadvantages of swapping proportioning valves?
Originally Posted by KoRn_vIRuZ
Calif_kid, so according to the parts catalogs, the disc-equipped EKs use the same part number as drum-equipped ones. Just like what I found to be the case for EGs. My research is just above your post. I can't believe Honda would make a serious mistake like this, not on two separate generation cars!
I also have an EK, but it has ABS so no issues there.
BTW, the different valve on the 2DR EX EK you mention might be due to 262mm front brakes?
So 262mm front /240 mm disc brakes use the same prop valve as 240mm front/drum rear. 262mm front/drum rear use a different one.
Good and interesting points... I'm not positive that the part numbers that are listed at the Honda/Acura websites are correct, but I expect that they probably are. The last five links I gave at least give the op some possible part numbers and info on what will fit his car. He may be able to find the part used, or even at a wrecking yard, but on my car, I only see some three number/letter sequences on the proportioning valve instead of 3040 or 4040, so if the op did go to a wrecking yard, then I'm not sure how confident he can be that he is getting a 4040 valve, but he can always take a look. - Jim
re: What are the advantages/disadvantages of swapping proportioning valves?
Assuming you have a 4040 prop valve I would first change your brake pad setup. I would first try a better rear brake pad, this will hopefully even out your front bias braking a bit, which is most likely causing you to overload the front end during hard braking. I run 11" front (Carbotech Xp10) and upgrading the rear disc to **** pad to a medium performance pad really helped a lot for the braking balance.
re: What are the advantages/disadvantages of swapping proportioning valves?
There is a reason most track driven and race cars use the 4040 prop valve out side of running an adjustable setup.
I made our enduro team switch to the 4040 when we swapped in the rear discs, and I have always raced with a 4040.
I thought I told you in one of your other threads about this to change it, and it should correct a lot of your issues you have experienced. You shouldn't be locking up like you have said unless you are too aggressive with the rear pad for your tires.
Just follow the herd on this one, its the right way to do it for the last like 20 years.
re: What are the advantages/disadvantages of swapping proportioning valves?
Originally Posted by known
There is a reason most track driven and race cars use the 4040 prop valve out side of running an adjustable setup.
I made our enduro team switch to the 4040 when we swapped in the rear discs, and I have always raced with a 4040.
I thought I told you in one of your other threads about this to change it, and it should correct a lot of your issues you have experienced. You shouldn't be locking up like you have said unless you are too aggressive with the rear pad for your tires.
Just follow the herd on this one, its the right way to do it for the last like 20 years.
Sounds good. I'll take your advice and update this thread when I do so, sir.
Re: What are the advantages/disadvantages of swapping proportioning valves?
Originally Posted by Calif_Kid
I decided to take a quick look at part numbers, and for a 2000 Civic Si (that has rear disc brakes), Honda Automotive Parts gives part number 46210-S04-902 as the proportioning valve. The strange thing to me, is that they list the same prop valve for 2dr DX, EX, HX and also for 3dr CX and DX with all of those using rear drums per the website. The 2dr EX (with rear drums) calls for prop valve 46210-S04-962, and I'm not sure why it calls for a different part. The 4dr DX and LX (rear drums) also use a different part number 46210-S04-912, but I guess that maybe the weight distribution is slightly different.
There is also a brake upgrade thread in the sticky section of the Brake & Suspension forum at https://honda-tech.com/forums/suspen...egras-3044628/ and around 30% of the way down the thread, there is a short section on 'Brake Bias - Proportioning Valve'.
I looked up the above part numbers for year 2000 as I had heard that a 99-00 Si has rear discs so figured that its rear prop valve would be setup for rear discs, but if the part numbers and info on the website are correct, then it looks like the same prop valve was also used for some rear drum brake equipped cars. I wasn't sure what prop valve part numbers fit a 1993 Civic though, but I looked at the Honda Civic/Del Sol (1992-2000) forum and found some threads that have info on a 4040 prop valve:
In reference to the EK valves. The 4 wheel disc cars use the same valve as the small disc/drum cars. The EX uses Si front brakes and rear drums, that's why it has a different valve. I just thought I'd throw that out there.
Re: What are the advantages/disadvantages of swapping proportioning valves?
If you go thru all the math, it turns out that the hydraulic pressure going to the rear calipers needs to be almost constant. The pressure going to the front is linear. That is a difficult combination to get to.
I set up autocross cars for slight oversteer as you late brake into a corner. This is done to avoid the situation in the second pic in this thread. In autocross, that is an unrecoverable situation. Most of the racecars I have built have balance bars built into the brakes. I used to know that on high grip surfaces, I needed to set the balance bar to X, and on slick surfaces, I set the bar to Y setting. High grip surfaces require way more front brake.
My CRX autocross car can hit 1.5 geez on the binders on Avons.
Re: What are the advantages/disadvantages of swapping proportioning valves?
Originally Posted by whittlebeast
If you go thru all the math, it turns out that the hydraulic pressure going to the rear calipers needs to be almost constant. The pressure going to the front is linear. That is a difficult combination to get to.
I set up autocross cars for slight oversteer as you late brake into a corner. This is done to avoid the situation in the second pic in this thread. In autocross, that is an unrecoverable situation. Most of the racecars I have built have balance bars built into the brakes. I used to know that on high grip surfaces, I needed to set the balance bar to X, and on slick surfaces, I set the bar to Y setting. High grip surfaces require way more front brake.
My CRX autocross car can hit 1.5 geez on the binders on Avons.
Woah, you're pulling moar G's under braking than in corners? That's wild. Something I've never seen on the track.
A balance bar is sick, but I don't think I'm going to splurge on my DE car. Also, it's probably not legal for H2 Honda Challenge-- and that's where I wanna be.
07-30-2016, 06:46 AM
What are the advantages/disadvantages of swapping proportioning valves?
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