Cheap Proportioning Valve Upgrade
Re: Cheap Proportioning Valve Upgrade
Any one still have a 30lb spring? pm or email me plz 01knightridergt@gmail.com
Joined: Feb 2000
Posts: 404
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From: Valley Center,Kansas
Car: 92RS
Engine: LS 402 inwork
Transmission: TH350
Axle/Gears: 10 bolt,3:73's
Re: Cheap Proportioning Valve Upgrade
I'm making the swap to manual brakes, will this spring mod still make an improvement?
If anyone has a spare spring PM me and I will Paypal you the funds
If anyone has a spare spring PM me and I will Paypal you the funds
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Joined: Mar 2007
Posts: 185
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From: Slinger WI
Car: 55 chevy Belair & 86IROC Z
Engine: 350 in 55 86IROC Z LT1
Transmission: 55 4speed IROC Z4L60e
Axle/Gears: 12 bolt 410 in55 and 342 inCamaro
Re: Cheap Proportioning Valve Upgrade
This for 4 wheel disc and improves rear disc brakes
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Joined: Sep 2006
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From: Long Island NY
Car: 88 Formula
Engine: 355
Transmission: worked 700r4 2500 stall
Axle/Gears: Strange Engineering 12 bolt 3:73
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Joined: Mar 2007
Posts: 185
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From: Slinger WI
Car: 55 chevy Belair & 86IROC Z
Engine: 350 in 55 86IROC Z LT1
Transmission: 55 4speed IROC Z4L60e
Axle/Gears: 12 bolt 410 in55 and 342 inCamaro
Re: Cheap Proportioning Valve Upgrade
part # 1ncf2 spring from Granger
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From: Charlestown, IN
Car: 1971 Camaro
Engine: 427
Transmission: TKO600
Axle/Gears: 3.73
Re: Cheap Proportioning Valve Upgrade
Did this the other day, mine was horrible, gummed up, spring stuck.
Front spring as bad, I'm sure, anyone know what spring would work for the front setup?
Front spring as bad, I'm sure, anyone know what spring would work for the front setup?
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Joined: Feb 2009
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From: Commerce Twp, MI
Car: '91 Camaro
Engine: LSx
Transmission: 4l60e
Axle/Gears: posi
Re: Cheap Proportioning Valve Upgrade
i just ordered some from Grainger today, pick them up tomorrow, cleaned up my prop valve, dirty and gummed up inside. I will have some left over
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Joined: Feb 2004
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From: So Cal
Car: 89 IROC Z28
Engine: 357 TPI
Transmission: 700R4
Axle/Gears: 3.42 Posi
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Joined: Feb 2009
Posts: 185
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From: Commerce Twp, MI
Car: '91 Camaro
Engine: LSx
Transmission: 4l60e
Axle/Gears: posi
Re: Cheap Proportioning Valve Upgrade
it should work with any 4 wheel disc, Im currently running CTS-V on all 4 corners on mine, which I had it set up with LS1 before
Joined: Mar 2013
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From: Darien IL
Car: 87 IROC
Engine: LT1
Transmission: T56
Axle/Gears: LS1 10bolt w/ 3.73
Re: Cheap Proportioning Valve Upgrade
hey guys, I have been through this thread and either i didnt see it or its not there, but has anyone run LS1 brakes front and rear with the spring change in a stock 87 drum prop valve? If so what spring?
Gregs_GSXR might be the best one to answer if you can.
Gregs_GSXR might be the best one to answer if you can.
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Joined: Dec 2001
Posts: 1,997
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From: Bartlett, IL
Car: 92 ZR-1
Engine: LT-5
Transmission: ZF-6
Axle/Gears: SuperDana 44 4.10
Re: Cheap Proportioning Valve Upgrade
I had C5 brakes on my 84 Vette. Doug Rippie sells a proportioning spring for that upgrade which I used. Worked fine. I think it was about $12.
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Joined: Feb 2009
Posts: 185
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From: Commerce Twp, MI
Car: '91 Camaro
Engine: LSx
Transmission: 4l60e
Axle/Gears: posi
Re: Cheap Proportioning Valve Upgrade
part # 1ncf2
i have some of these left over and is what Im running on my current set up
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From: NYC
Car: 1982 Recaro TA, 1989 TTA#948
Re: Cheap Proportioning Valve Upgrade
Joined: Apr 2005
Posts: 311
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From: Lombard IL
Car: 1989 TA
Engine: 406
Transmission: 400
Axle/Gears: 9 inch
Re: Cheap Proportioning Valve Upgrade
I understand that but with wilwood and 13" roters on front and the crap irons on the rear my fronts Do all the work Just looking for more out of the rear
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From: NYC
Car: 1982 Recaro TA, 1989 TTA#948
Re: Cheap Proportioning Valve Upgrade
If you lock up the rears first, the rear will kick out and you will lose control of the car. Very dangerous - it's your car but it is very irresponsible to do something like that and put everyone else in danger who happens to be on the road when you lose control.
Put in an adjustable proportioning valve and consider beefing up the rear brakes to a better set up so you get the bias set properly.
Put in an adjustable proportioning valve and consider beefing up the rear brakes to a better set up so you get the bias set properly.
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From: Charlestown, IN
Car: 1971 Camaro
Engine: 427
Transmission: TKO600
Axle/Gears: 3.73
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From: Charlestown, IN
Car: 1971 Camaro
Engine: 427
Transmission: TKO600
Axle/Gears: 3.73
Re: Cheap Proportioning Valve Upgrade
I have a few springs left as well. $5 shipped. PM me if interested.
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Joined: May 2009
Posts: 225
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From: Bergen, Norway
Car: '87 Camaro SC
Engine: 305 LG4
Transmission: TH-700R4
Axle/Gears: 3.42
Re: Cheap Proportioning Valve Upgrade
Just saw this thread. Why have I not seen this thread before?!?
Anyways. Looking for a spring to put in my 87. I've got LS1/C5 front and stock drums rear with the original prop valve. Rears will keep turning when the car is jacked up and brake pedal floored, so I definitely need to do something about that.
(...)
In my original post I asked if anyone could send a spring to Norway where I live, mainly because I didn't know of any places in Norway that makes springs like these. But now I might have found someone who does. But I wanted to check if the measurements I've used are correct.
So I am looking at four different springs:
- They all have an outside diameter of 12.19mm, which should convert to .480"
- They all have an uncompressed length of 38.10mm, which should be 1.5"
Spring #1 has a thickness of .055", an inside diameter of .37", 13.5lb and a spring rate of 18.33lb/inch
Spring #2 has a thickness of .059", an inside diameter of .36", 15.5lb and a spring rate of 24.67lb/inch
Spring #3 has a thickness of .063", an inside diameter of .35", 19.1lb and a spring rate of 31.63lb/inch
Spring #4 has a thickness of .067", an inside diameter of .34", 22.3lb and a spring rate of 40.31lb/inch
Will any of these fit my car and application?
Also, are you guys changing the prop valve, or the metering valve?
Thank you.
-Dennis
Anyways. Looking for a spring to put in my 87. I've got LS1/C5 front and stock drums rear with the original prop valve. Rears will keep turning when the car is jacked up and brake pedal floored, so I definitely need to do something about that.
(...)
In my original post I asked if anyone could send a spring to Norway where I live, mainly because I didn't know of any places in Norway that makes springs like these. But now I might have found someone who does. But I wanted to check if the measurements I've used are correct.
So I am looking at four different springs:
- They all have an outside diameter of 12.19mm, which should convert to .480"
- They all have an uncompressed length of 38.10mm, which should be 1.5"
Spring #1 has a thickness of .055", an inside diameter of .37", 13.5lb and a spring rate of 18.33lb/inch
Spring #2 has a thickness of .059", an inside diameter of .36", 15.5lb and a spring rate of 24.67lb/inch
Spring #3 has a thickness of .063", an inside diameter of .35", 19.1lb and a spring rate of 31.63lb/inch
Spring #4 has a thickness of .067", an inside diameter of .34", 22.3lb and a spring rate of 40.31lb/inch
Will any of these fit my car and application?
Also, are you guys changing the prop valve, or the metering valve?
Thank you.
-Dennis
Last edited by 87_LG4; Feb 10, 2014 at 11:22 AM. Reason: Just wanted to try out my new signature image :)
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Joined: May 2009
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From: Bergen, Norway
Car: '87 Camaro SC
Engine: 305 LG4
Transmission: TH-700R4
Axle/Gears: 3.42
Re: Cheap Proportioning Valve Upgrade
Tried the 15.5 lbs spring this weekend. It really made an improvement on my LS1/drum setup. Only had time to do a short drive without any hard braking, but the pedal feels better and the brakes grip firmer and faster than before. Now I actually believe my brakes can stop my car. Probably one of the quickest and cheapes upgrades anyone can do to these cars. Love it
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From: NC now
Car: 83 L69 Z28 T tops
Engine: 305 H.O.
Transmission: 5 spd
Axle/Gears: 3:73
Re: Cheap Proportioning Valve Upgrade
Been reading all the threads on the brakes. I have a 83 Z28 with 4 wheel disc, ordered it new, and the rear brakes have never worked. Rotors and pads are like new, 66K mi. So far I've replaced the MC, PPV, and no luck. Bought a new PPV from Summit and the brakes worked fine after they were bled. Then while holding the pedal it went down and they haven't worked again. checked the lines to see if they were plugged and they're clear. I'm at a loss, been doing this for close to 50 yrs. and never had this much trouble with brakes. Just went to bone yard and got a PPV off an 87, looks like the one in the threads got springs to change the spring just hate to change the fittings to metric and not have it work. When you push on the pedal good fluid comes out of the MC for the front breaks but the rear just seems to run out very slow unless you jam on the brake pedal then it will shoot out. Trying to keep it stock. Allot of great information in these threads hope someone can help an old Camaro guy out.
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From: Waxahachie Texas
Car: 88 IROC Z/28-under re-construction
Engine: 5.7 Tuned Port
Transmission: It's in there....
Axle/Gears: 9 bolt Borg-Warner
Re: Cheap Proportioning Valve Upgrade
Just placed an order and will have xtra
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From: Waxahachie Texas
Car: 88 IROC Z/28-under re-construction
Engine: 5.7 Tuned Port
Transmission: It's in there....
Axle/Gears: 9 bolt Borg-Warner
Re: Cheap Proportioning Valve Upgrade
got them today
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Joined: Oct 2001
Posts: 8,113
Likes: 6
From: NWOhioToledoArea
Car: 86-FireBird
Engine: -MPFI
Transmission: T5
Axle/Gears: 3:42
Re: Cheap Proportioning Valve Upgrade
My upgrade was to get a Disc/Drum brass hotrod prop valve off ebay and convert everything to standard lines.
[ditching the metric line stuff]
[ditching the metric line stuff]
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Joined: Mar 2012
Posts: 324
Likes: 0
From: orlando fl
Car: 92 camaro RS
Engine: vortec 350/396
Transmission: T5
Re: Cheap Proportioning Valve Upgrade
If I keep stock 3rd gen rearemnd and pull drums off and put factory 3rd gen disc brakes on the rear. Will I have to upgrade the spring or get a proportioning valve off a factory disc brake car?
Joined: Jan 2003
Posts: 642
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From: Northern New Jersey
Car: 1988 Trans am GTA
Engine: corvette 350 swap
Transmission: t-5 swap
Axle/Gears: 3.27:1 borg warner 9-bolt w/ PBRs
Re: Cheap Proportioning Valve Upgrade
Good luck finding a disk brake prop valve. The spring upgrade is definitely worthwhile.
Also I have 4 springs left.
Also I have 4 springs left.
Member
Joined: Mar 2012
Posts: 324
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From: orlando fl
Car: 92 camaro RS
Engine: vortec 350/396
Transmission: T5
Re: Cheap Proportioning Valve Upgrade
Im at junkyard right now getting two of them. Lol. I got the disc brake setuo off this same car last weekend but didnt think about the prop valve. But there is two rear disc brake camaros here at the yard one is already stripped though. Nobody sells the prop valve new for disc brakes?
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Joined: Mar 2012
Posts: 324
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From: orlando fl
Car: 92 camaro RS
Engine: vortec 350/396
Transmission: T5
Re: Cheap Proportioning Valve Upgrade
Im at junkyard right now getting one now. Lol. I got the disc brake setuo off this same car last weekend but didnt think about the prop valve. But there is two rear disc brake camaros here at the yard one is already stripped though. Nobody sells the prop valve new for disc brakes?
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Joined: Oct 2001
Posts: 8,113
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From: NWOhioToledoArea
Car: 86-FireBird
Engine: -MPFI
Transmission: T5
Axle/Gears: 3:42
Re: Cheap Proportioning Valve Upgrade
no one sells them direct fit, but you can find plenty of uni hotrod brass prop valves, in disc disc or disc drum....... nothing about a prop valve makes it a one car design.
Id avoid junk yard million mile parts and longevity......
Id avoid junk yard million mile parts and longevity......
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From: Brick, NJ
Car: 1987 Z28
Engine: 350
Transmission: Auto
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Posts: 627
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From: Waxahachie Texas
Car: 88 IROC Z/28-under re-construction
Engine: 5.7 Tuned Port
Transmission: It's in there....
Axle/Gears: 9 bolt Borg-Warner
Joined: Jun 2003
Posts: 504
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From: Oak Harbor, WA
Car: 1990 IROC-Z
Engine: 383 HSR
Transmission: 700R4
Axle/Gears: 3.70
Re: Cheap Proportioning Valve Upgrade
I just ordered a pack of 5; 1NCR5. Expected delivery of Tuesday, Pm me if you need one.
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Joined: Feb 2014
Posts: 5
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From: NC now
Car: 83 L69 Z28 T tops
Engine: 305 H.O.
Transmission: 5 spd
Axle/Gears: 3:73
Re: Cheap Proportioning Valve Upgrade
Got the brakes done. Got a Proportioning valve bleed tool and help out with the bleeding.
Works real good if you don't have one in your toolbox your missing out takes the proportion valve issues out of bleeding brakes. Used a new proportioning valve from Summit, rear brakes work great. Thanks to third Gen.org for all the help.
Works real good if you don't have one in your toolbox your missing out takes the proportion valve issues out of bleeding brakes. Used a new proportioning valve from Summit, rear brakes work great. Thanks to third Gen.org for all the help.
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Car: 1991 firebird
Engine: TBI 305 (built)
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Axle/Gears: 4.10
91' bird 305 TBI T-5, trick flow heads, 4.10 gears, full UMI setup, track times coming soon!
Joined: Dec 2012
Posts: 206
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From: cape cod ma
Car: 1988 gta
Engine: 383
Transmission: 700r4
Axle/Gears: 9 bolt 3:23
Re: Cheap Proportioning Valve Upgrade
Using the 1ncr5 spring. Can anybody recommend another spring for more rear brake pressure?
Joined: Mar 2011
Posts: 547
Likes: 27
From: Germany
Car: 1990 Trans Am
Engine: 305 TPI
Transmission: Auto
Axle/Gears: Stock
Re: Cheap Proportioning Valve Upgrade
Hey guys,
I was thinking.
My car and at least one other F-body and one other car are having the issue of the drums locking up fairly quickly even with moderate pedal pressure.
What would happen if the spring in the prop valve were to weaken over the years and lose some force?
I guess it would compress real easy and give way to the pressure coming down the line, just like when someone slams the brakes.
Is this correct?
I was thinking.
My car and at least one other F-body and one other car are having the issue of the drums locking up fairly quickly even with moderate pedal pressure.
What would happen if the spring in the prop valve were to weaken over the years and lose some force?
I guess it would compress real easy and give way to the pressure coming down the line, just like when someone slams the brakes.
Is this correct?
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From: Minnesota
Car: 89 IROC-Z
Engine: 370 LSX, LS3 Top End
Transmission: Built T-56
Axle/Gears: 9" Aluminum Center 3.89's
Re: Cheap Proportioning Valve Upgrade
I need an R5 and will pay shipping. If someone has one please PM me!!!








