dgangle said:
In a thread I started a while back, Poser enlightened me with those dates and I'm sure he could expand on it better than I could.
That's crazy that you had the same setup and those results??? Somethin wierd. Sorry not much help.
Brake Proportioning Valve for FJ40 (1 Viewer)
- Thread starter Jerzfj40
- Start date
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In a thread I started a while back, Poser enlightened me with those dates and I'm sure he could expand on it better than I could.
That's crazy that you had the same setup and those results??? Somethin wierd. Sorry not much help.
I think it's going to be trial and error. With so many cruisers configured so many ways it will be impossible to determine what brake options will work for you. If we could have a post where everyone describes there non stock brake setup and cruiser configuration then we might have a chance of helping someone. Though the proportioning valve gives you a better range of adjustment it may not be the best fix.
Just think of the varables.
SOA Vs. SUA (the center of gravity is changed as well as geometry
Engine (2F, sbc, diesel, etc)
Tires (M/T, swampers, A/T, narrow, fat hard soft compounds)
Brake pads used (carbon, semi metalic)
Brake lines (my rear brake lines all of them are braided hoses)
Brake boosters
Shocks ( different shock affect braking performance in different ways)
other accesories that add weight to the front or rear (gas tank location, winch, compressors, Bumpers, Roll cages, etc...)
Shackles (I'm sure my hyper shackles effect my braking performance)
Springs (some are a lot stiffer than others)
Then there are calipers (stock, monte carlo, 4runner, etc...)
And the most important Brake master (stock, 80 series, corvette, asin, etc...)
I really think it is impossible to tell someone exactly what will work for them. Considering the thousands of different configurations. But I can say that if you are not lucky on the initial setup that a propotioning valve will get you closer to your goal. I have been lucky and not had to go this route.
Just think of the varables.
SOA Vs. SUA (the center of gravity is changed as well as geometry
Engine (2F, sbc, diesel, etc)
Tires (M/T, swampers, A/T, narrow, fat hard soft compounds)
Brake pads used (carbon, semi metalic)
Brake lines (my rear brake lines all of them are braided hoses)
Brake boosters
Shocks ( different shock affect braking performance in different ways)
other accesories that add weight to the front or rear (gas tank location, winch, compressors, Bumpers, Roll cages, etc...)
Shackles (I'm sure my hyper shackles effect my braking performance)
Springs (some are a lot stiffer than others)
Then there are calipers (stock, monte carlo, 4runner, etc...)
And the most important Brake master (stock, 80 series, corvette, asin, etc...)
I really think it is impossible to tell someone exactly what will work for them. Considering the thousands of different configurations. But I can say that if you are not lucky on the initial setup that a propotioning valve will get you closer to your goal. I have been lucky and not had to go this route.
- Thread starter
- #23
OK...figured it out!!!
OK...i finally installed the Wilwood adjustable proportioning valve on my 77 fj40. The valve came with two 1/8 -27 NPT to 3/8-24- inverted flair fittings to adapt double flared hard brake lines to the valve. All i had to do was remove the existing brake line from M/C to factory valve and cut off the fitting that went to the factory proportioning valve bolted on the brake booster. You will need to buy 2 new 3/8-24 fittings that will screw into the Wilwood supplied fittings. ( unbolt and discard factory proportioning valve) and using a double flaring tool, re - flare the hard line and bend to fit to new valve and it bolts right in. Use the same procedure to connect line from "out" side of valve to brake calipers.
With the adjustable valve , now my cruiser stops without the lock up problem!
I hope this is helpful for anyone with the same problem
OK...i finally installed the Wilwood adjustable proportioning valve on my 77 fj40. The valve came with two 1/8 -27 NPT to 3/8-24- inverted flair fittings to adapt double flared hard brake lines to the valve. All i had to do was remove the existing brake line from M/C to factory valve and cut off the fitting that went to the factory proportioning valve bolted on the brake booster. You will need to buy 2 new 3/8-24 fittings that will screw into the Wilwood supplied fittings. ( unbolt and discard factory proportioning valve) and using a double flaring tool, re - flare the hard line and bend to fit to new valve and it bolts right in. Use the same procedure to connect line from "out" side of valve to brake calipers.
With the adjustable valve , now my cruiser stops without the lock up problem!
I hope this is helpful for anyone with the same problem
Good to hear it.
Bodean
Hot Damn
A 1990 Toyota Supra (non-abs) M/C works perfect. Bolts right up and it's set up for 4 wheel disc.
Later,
Later,
dgangle
total rice
Bodean said:
Any pictures? Bore size? Tell me more. At $177.59 Id like to know a little more before throwing more $$ at the problem.
76 FJ-40 Front Brakes, MC, & Monte Carlo Rear Discs
Here's my experience...... I did some brake system "modeling", and I found out that the "ideal" hydraulic pressure on the rear disc should be about 250 psig. That's with my 5200 Lb Cruiser, and lots of assumptions (like 60% front braking and 40% rear braking). My modeling suggests that the Monte Carlo disc/pad system is really too large. The front brakes from the Monte Carlo are just too big for the rear of our 40's. And the result of this is ...... the rear brakes will lock up too easily.
Knowing this, I elected to continue using the stock proportioning valve in series with the new Summit adjustable proportioning valve. Glad I did!
With the Summit adjustable proportioning valve dialed fully clockwise (CW) for maximum hydraulic pressure to the rear brakes, I measured 850 psig. And, yes, my brakes locked up too easily.
I ended up with the Summit valve adjusted almost fully CCW and the hydraulic pressure is now about 460 psig. With this setup, my brakes are excellent in a straight line stop on pavement. With my center of gravity so high, I still am very cautious in braking while going around a corner; the inner rear brake will still lock up.
I said all of this to offer the suggestion that you might install a pressure gauge to help diagnose your problems.
Here's my experience...... I did some brake system "modeling", and I found out that the "ideal" hydraulic pressure on the rear disc should be about 250 psig. That's with my 5200 Lb Cruiser, and lots of assumptions (like 60% front braking and 40% rear braking). My modeling suggests that the Monte Carlo disc/pad system is really too large. The front brakes from the Monte Carlo are just too big for the rear of our 40's. And the result of this is ...... the rear brakes will lock up too easily.
Knowing this, I elected to continue using the stock proportioning valve in series with the new Summit adjustable proportioning valve. Glad I did!
With the Summit adjustable proportioning valve dialed fully clockwise (CW) for maximum hydraulic pressure to the rear brakes, I measured 850 psig. And, yes, my brakes locked up too easily.
I ended up with the Summit valve adjusted almost fully CCW and the hydraulic pressure is now about 460 psig. With this setup, my brakes are excellent in a straight line stop on pavement. With my center of gravity so high, I still am very cautious in braking while going around a corner; the inner rear brake will still lock up.
I said all of this to offer the suggestion that you might install a pressure gauge to help diagnose your problems.
I use a Jegs prop valve and simply flared the sock lines with a standard flare tool for the jegs fittings and metric for the master cylinder, have a previa mini van master that is 4wdb non abs, works great so far, also running a mini truck booster. Flareing the lines is not that difficult once you practice 5-10 times on so spare line, the less adapters and fittings, the less possibility for leaks.
I found a pre-made 3/16" brake line at Auto Zone that seems to have the proper fittings. See below.
They only sell these in 8" lengths, I am going to try and install the other one line this weekend. It is going to be pushing it to get it over to the the bottom fitting on the three way. I will post a picture once it is complete.
Can someone check and see if I plumbed this right? The one on the top is the front brake. The one on the three way is the rear brake.
Can someone check and see if I plumbed this right? The one on the top is the front brake. The one on the three way is the rear brake.
you want the proportioning valve in the rear circuit so that you can prevent the rear from locking up before the front
which way you orient the valve does not really matter, it will only affect the direction in which you turn the knob to close or open the valve
which way you orient the valve does not really matter, it will only affect the direction in which you turn the knob to close or open the valve
Which valve did you get? The ony wilwood porportioning valves I find ony have one inlet/outlet, mines all jammed upDitto, 'cept my valve is from Summit.
A little late spencer, but I think this is the one that I used.
JEGS Performance Products 63020, JEGS Adjustable Proportioning Valve | JEGS Performance Products
JEGS Performance Products 63020, JEGS Adjustable Proportioning Valve | JEGS Performance Products
Thanks man, I got it figured out with a combination of a new wilwood one from summit and a 60 series Aisn one off of one of my parts cruisers. I actually sold the 40 in October!
you didn't say which mc you are using but I used one from a fjz80 abs I was having rear lock up problems and just really bad breaking to where it was dangerous and almost rear ended people. It turned out (after trying an adjustable prop valve and everythng else) that the front port on the mc needed to feed the rear lines and vice versa. Not all mc's do this but the one I got was for a fjz80 it said abs on the side of the reservior and it had a front port that came out from the top. All this may be useless info to you but thought it might help others with similar problems.
This is an older post thread, but hoping to get some feedback.
I have had the JT Outfitters 4 wheel disc conversion installed for almost a year. Normal breaking works fine. When I hit it them hard the rear does lock up first and the fronts not at all. The MC is the AISIN with top fitting on end and rear one coming out at a 45deg angle rearward. Seen a couple of post now that put into question which fitting goes to which axle.
If I lock up rear now would it not make sense to reverse it as the first course of action? Don't want to mess with proportioning valves if it's as easy as changing MC connections and bleeding...
Thx,
LR
So did you do the conversion? Do you know if you put a new porporioning valve on when you put the discs on? I didn't do mine so I don't know what the stock valve was like but here's what I know: as far as I know you should only have one. It will be by your brake booster or master cylinder, you can follow back the brake lines to it. My stock 60 has it up bolted to the booster on the same bolts that bolt the master cylinder to it but that is not adjustable so if you have that set up most likely it is going bad and needs to be replaced. If you find an adjustble one (mine had a knob on it) play with that knob till it feels right. The porportioning valve basically just controls where the fluid pressure goes to first.
Can't hurt to purge your brakes and flush everything out including old fluid. I always do that before spending good money on brakes.
Also I think if you have an adjustable valve then turn it counterclockwise to get the front opened up
