Proportioning valve? |
Post Reply | Page 12> |
Author | |
Siskiwit
Member Joined: 23 Dec. 2013 Location: 54827 Status: Offline Points: 166 |
Post Options
Thanks(0)
Posted: 17 Mar. 2019 at 11:12am |
I will be installing a Suzuki disk brake conversion on my Willy’s. I was wondering if it would be wise to put a adj. proportioning valve in also. I read that it may not be needed with the weight distribution of the JEEP. What do you think? I have a $20 coupon for Summit and wondering if I should use it for other parts.
|
|
'48 2a - '46 2a - '54 3b - '70 cj5 and a bunch of accessories.
|
|
Mark W.
Member Sponsor Member Joined: 09 Nov. 2014 Location: Silverton, OR Status: Offline Points: 7923 |
Post Options
Thanks(0)
|
Well on a normal vehicle 60% of the braking is done by the front wheels. In a hard stop the weight leans forward. This causes the rear wheels to loose traction if your brakes are applied with the same amount of force front to rear then the greater weight on the front and the reduced weight on the back will cause the rear wheels to skid. A tire in skid has NO CONTROL if you are on a corner or even a road with a decent super (OK the public would call it a crown) then the ass end of your jeep will slide down the slope while the rear tires are in skid. Brake systems without a Proportioning valve will bias the front to rear by having different sized wheel cylinders. I would assume your disc brake set up dose not have smaller pistons on the rear. You also need to put 2lb residual pressure valves in a Disc brake system one in the front line one in the rear line. Drum brakes should use 10lb valves. YES YOU SHOULD USE A PROPORTIONING VALVE. |
|
Chug A Lug
1948 2A Body Customized 1949 3A W/S 1957 CJ5 Frame Modified Late 50's 134L 9.25"clutch T90A D18 (1.25") D44/30 flanged E-Locker D25 5.38 Since 1962 |
|
rocnroll
Member Sponsor Member Joined: 20 July 2005 Location: Tuscumbia, AL Status: Offline Points: 13562 |
Post Options
Thanks(0)
|
Just fronts or front & rear? |
|
'47 CJ2A PU
'48 CJ2A Lefty "Common sense is not that common" |
|
Siskiwit
Member Joined: 23 Dec. 2013 Location: 54827 Status: Offline Points: 166 |
Post Options
Thanks(0)
|
All four corners
|
|
'48 2a - '46 2a - '54 3b - '70 cj5 and a bunch of accessories.
|
|
otto
Member Joined: 26 Feb. 2012 Location: Orygun Status: Offline Points: 2240 |
Post Options
Thanks(0)
|
Did Suzuki fit the donor vehicle with a valve? If one was used on a Sidekick or Samarai you could just use a factory part.
|
|
47 CJ2A w/fuel injected boat engine
48 CJ2A 64 Ford Econoline Travelwagon If you can't get there in a Jeep, get a motorcycle! |
|
Siskiwit
Member Joined: 23 Dec. 2013 Location: 54827 Status: Offline Points: 166 |
Post Options
Thanks(0)
|
I think I will install one. I just read that it probably wasn’t needed or hasn’t been needed on a cj2a by the guy that made the conversion kit if I remember right. I haven’t set up a brake system before so everything is new to me and want to do it right the first time. I’m going with a Wildwood dual master with a remote resivoire. One more thing I understand I will need a couple of 2 psi. Residual valves, where are they plumbed in? I am guessing after the proportioning valve going to the front and rear.
|
|
'48 2a - '46 2a - '54 3b - '70 cj5 and a bunch of accessories.
|
|
Stev
Member Sponsor Member Joined: 27 July 2016 Location: Cincinnati Status: Offline Points: 2383 |
Post Options
Thanks(0)
|
Sikiwit,
I put a proportioning valve in after I did the Geo Tracker disc brake conversion because the rears (still drums) were locking up before the fronts and --- the rear end of the Jeep was coming around when the rears locked up. I also have a dual master cylinder from Herm. |
|
Stev
1946 CJ2A Trail Jeep (The Saint), 1948 CJ2A Lefty Restored |
|
Siskiwit
Member Joined: 23 Dec. 2013 Location: 54827 Status: Offline Points: 166 |
Post Options
Thanks(0)
|
Thanks for the info.
|
|
'48 2a - '46 2a - '54 3b - '70 cj5 and a bunch of accessories.
|
|
Mark W.
Member Sponsor Member Joined: 09 Nov. 2014 Location: Silverton, OR Status: Offline Points: 7923 |
Post Options
Thanks(0)
|
Residual pressure valves go between the pistons and prop valve they are ment to stop leak back in disc brakes and to keep the springs in a drum brake system from pushing fluid back to the MC.
Edited by Mark W. - 18 Mar. 2019 at 3:10am |
|
Chug A Lug
1948 2A Body Customized 1949 3A W/S 1957 CJ5 Frame Modified Late 50's 134L 9.25"clutch T90A D18 (1.25") D44/30 flanged E-Locker D25 5.38 Since 1962 |
|
Siskiwit
Member Joined: 23 Dec. 2013 Location: 54827 Status: Offline Points: 166 |
Post Options
Thanks(0)
|
Thanks for the exact info I was looking for. Like I said before I don’t know shat about brake systems other than the obvious. . I know now what parts to order. Thanks a lot.
|
|
'48 2a - '46 2a - '54 3b - '70 cj5 and a bunch of accessories.
|
|
Mark W.
Member Sponsor Member Joined: 09 Nov. 2014 Location: Silverton, OR Status: Offline Points: 7923 |
Post Options
Thanks(0)
|
Siskiwit you only need one per circuit so put the Residual pressure valve between the Tee where your line splits right and left and the Proportioning valve. |
|
Chug A Lug
1948 2A Body Customized 1949 3A W/S 1957 CJ5 Frame Modified Late 50's 134L 9.25"clutch T90A D18 (1.25") D44/30 flanged E-Locker D25 5.38 Since 1962 |
|
Rick G
Member Joined: 17 May 2015 Location: Amarillo, TX Status: Offline Points: 1467 |
Post Options
Thanks(0)
|
Siskiwit,
I have 4 wheel discs (the large GM calipers) and I don’t use any proportioning valves or residual valves. I originally installed the residual valves fore and aft, but have since done away with them. I have had zero problems with my brake system without either type of these valves. I’ve been wheelin pretty hard with this setup for 4 years now. I never have to worry about my brakes. HTH, Rick
|
|
chasendeer
Member Joined: 24 Feb. 2012 Location: Napa,CA Status: Offline Points: 1080 |
Post Options
Thanks(0)
|
Rick What master do you have? Thanks Jay
|
|
Rick G
Member Joined: 17 May 2015 Location: Amarillo, TX Status: Offline Points: 1467 |
Post Options
Thanks(0)
|
Wilwood 1” with dual remote reservoirs.
|
|
Metcalf
Member Sponsor Member Joined: 21 May 2009 Location: Durango, Co Status: Offline Points: 736 |
Post Options
Thanks(0)
|
With 4-wheel disc brakes, I don't think a proportioning valve is required on a flat fender. The weight distribution is close enough front to rear it doesn't seem to be an issue. Most of the tires used on early jeeps can't really generate a ton of brake force before they lock up and slide. I installed one on mine when I designed and built my Sidekick/Tracker conversion. I have played with a lot, and I don't see much difference. It does create another leak point or three which is annoying, because most aftermarket units use NPT threads and adapters. With discs on just the front axle, a proportioning valve seems to be required more often to keep things more balanced between the different braking systems. A residual valve helps keep LIGHT pressure on the piston to help deal with any lateral concentric runout of the rotor to the caliper. The caliper can typically float in it's mount inboard and outboard, but the rotor can push fluid out of the piston depending on the force required. The residual valve helps this. Without one, you basically just have to push more fluid ( more pedal travel ) before things can lock up. This can cause a softer pedal feel at the top of the stroke. |
|
42 MB that had a one night stand with a much younger 69 CJ5 and a 50s GM truck.
|
|
Siskiwit
Member Joined: 23 Dec. 2013 Location: 54827 Status: Offline Points: 166 |
Post Options
Thanks(0)
|
That’s why I considered not installing one, extra leak points. I think I’ll plumb the brakes without one first and if I find I need one I’ll put one in. Thanks
|
|
'48 2a - '46 2a - '54 3b - '70 cj5 and a bunch of accessories.
|
|
jpet
Moderator Group Sponsor Member x 5 Joined: 30 Apr. 2008 Location: Ramsey, IL Status: Offline Points: 11173 |
Post Options
Thanks(0)
|
|
|
CJ2A #29110 "General Willys"
MB #204827 "BAM BAM" "We do what we can, and we try what we can't" |
|
LesBerg
Member Joined: 09 Apr. 2014 Location: Athol, ID Status: Offline Points: 1554 |
Post Options
Thanks(0)
|
OK. I guess I'm going against the grain.
I installed a proportioning valve on mine after completing the four-corner Suzuki disk brake conversion. I found that panic-braking on dirt/gravel without it caused the rear to lock up well before the front. I want to be in full control on mountain roads. That said, I'm still running the factory master cylinder on a jeep with a two-foot stretch, powered by a 225 Dauntless. Given that my wheelbase is 24" longer with a slightly lighter engine, my weight distribution is doubtlessly different from stock. If your line-flare skills are up to par (mine aren't) then potential extra leak points shouldn't be an issue. I guess the best advice would be to go drive it for a while. If you find that the back locks up unexpectedly or more often than you'd like, install a proportioning valve.
|
|
1948 CJ2A 157713 24" Stretch "Old Ironsides"
1st Armored Div 6th Infantry Reg 3rd Infantry Bn Headquarters Company #161 rubigo in quo speramus - "In Rust we Trust" |
|
Post Reply | Page 12> |
Tweet |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |