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I own a 1989 Milano gold.

I have looked for ways to improve the car without resorting to many costly alfa romeo specific parts.

From the moment I got the car I hated how the car behaved under hard braking and even concidered getting rid of it, the front brakes would lock up under braking (not very heavy braking either) and not allow you to turn in. After much *****ing about this prob my friend George suggested getting an adjustable brake proportioning valve.

We went to a couple of shops at Sears Point and bought one that had a rotary adjustment, brake line, and a crimping tool for a total of $80. After removing and kicking the stock proportioning valve as hard as I could, which dumps all the brake pressure to the front two tires (and unevenly), we installed the new adjustable valve.

After a couple of trial runs and dialing in much rear biased the car became fun and safer, especially with a set of EBC green brake pads. I could brake much deeper and harder and still turn in. I am doing this upgrade to any car I own.

R.
 

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I want to do that to my Verde next as the front brake bias is pretty bad too. It's almost put me into a dirt wall before, as I am used to rotating cars by braking. Driver error obviously, but i'd like to tailor the car to my driving style.

The problem with the bias valve is that you're sending more brake pressure to the rear brakes. The rears are overworked as it is being next to the transmission with little airflow and once you go to the track or haul a$$ down a mountain, I'd be really worried about fading in the rear. I don't think I'm going with an adjustable valve until I figure out better cooling for my rear brakes.
 

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strange my Verde lock up the back first with the ABS off.
I also have to change the back pads like 2 or 3 times as often as the front.
but a hard hit or panic and the back starts to come around. and as a rule it shoots to the right.
I think that has saved me a few times anyone behind me notice when the car starts to go sideways and stops fast vs runing in to me.. as well as it seem to give a faster stop by rotating the car. at lest it seems that way.
 

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From the moment I got the car I hated how the car behaved under hard braking and even concidered getting rid of it, the front brakes would lock up under braking (not very heavy braking either) and not allow you to turn in. After much *****ing about this prob my friend George suggested getting an adjustable brake proportioning valve.
OK, a couple of things:

1) It sounds like your stock proportioning valve was not functioning correctly. While the stock valve is front-biased, it should not lock up the fronts that easily (unless you are running really bad tires, which I suspect you are not).

2) For a nice upgrade using Alfa parts, you can subsituted the GTV/6 proportioning valve for more rear bias.

3) Others are discussing the Verde/Platinum ABS system, which is significantly different and does seem to have more rear bias. I think Alfa was afraid to dial in too much rear bias for fear of rear lock-up in the rain, etc. with the non-ABS cars. With the ABS system taking care of lock-up, they changed the balance more to the rear.

Joe
 

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The stock braking valve was functioning properly, that is, it sucked. Why use an expensive alfa part when you can use a vastly superior aftermarket part? Alfa parts suppliers come up with these wicked prices and all they succeed in doing is having people selling off their cars to later be scrapped. I put my $40 part against anything that alfa produces. As for rear brake fade, well, I have yet to notice it 20 minute sprints. I drive super hard during that time and the EBC front pads have performed flawlessly.
R.
 

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Sing it with me! "...O-mazin' brakes..." :confused:

Never let a crack-head sing at your funeral - :eek:


Sorry, couldn't resist! :D Please don't respond here - OT - and this is a worth-while upgrade...
 

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Never let a crack-head sing at your funeral

Well, JJ. If it's your funeral, how much choice do you really have? Better to not dwell on it and instead get down to Ivar's for a bowl of chowder.
 

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I want to do that to my Verde next as the front brake bias is pretty bad too. It's almost put me into a dirt wall before, as I am used to rotating cars by braking. Driver error obviously, but i'd like to tailor the car to my driving style.

The problem with the bias valve is that you're sending more brake pressure to the rear brakes. The rears are overworked as it is being next to the transmission with little airflow and once you go to the track or haul a$$ down a mountain, I'd be really worried about fading in the rear. I don't think I'm going with an adjustable valve until I figure out better cooling for my rear brakes.
True. One way to combat that is to drill and slot the rear rotors, being solid and not vented that could help reduce fade. Same reason motorcycle rotors are all drilled, not for looks but for performance since they are solid front and rear. On a vented rotor I always like to stay solid actually.
Also maybe some ducts to bring air onto the rotors may help as well. But I would think there should be plenty of air under there to keep them cool and even with more rear bias they should be able to handle it. There are a few out there with drilled and slotted rears.

Jason

"The stock braking valve was functioning properly, that is, it sucked. Why use an expensive alfa part when you can use a vastly superior aftermarket part? Alfa parts suppliers come up with these wicked prices and all they succeed in doing is having people selling off their cars to later be scrapped. I put my $40 part against anything that alfa produces. As for rear brake fade, well, I have yet to notice it 20 minute sprints. I drive super hard during that time and the EBC front pads have performed flawlessly.
R."

Not sure where this info comes from and what it is based on?
We don't come up with the wicked prices, there are a ton of factors involved with those "wicked" prices. First off most alfa parts are most likely 2-3 times less expensive than Honda, toyota, VW whatever.
Second the prices are based on a few important things, 1 being what alfa sells it to us, 2 the EURO!! (1.369 today), thats no help, 3. Frieght and Shipping. In the grand scheme of things the parts are general not bad at all in-fact I see them fairly reasonable. Usually brake parts are made by ATE, Bendix-italia, Bosch, Lucas/Girling and not really by Alfa at all, or course made for Alfa.
Please don't come down on the suppliers. We are not all that crazy with prices. So sure the brake valve is around $125.00 my price for example. Most Toyota for example are ranging from $175 and up, a lot cheaper than after market sure but I am also not sure the quality is any better but maybe. Not every part on any car is superior. That is why there is an after market. I can buy a Audi A8 and I am sure there are a slew of crappy parts on that vehicle and that car is $100K+ car new. I think over the years a BPV may just go bad, it happens.
Anyways good luck with your upgrade.
 

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Jason, what are you basing your experience on? Drilling the solid rotors seems like it would help (if I take them off I might as well switch over to vented rotors though) but I know of atleast 2 Milanos that were fading their brakes this last weekend at the track in very hot weather with stock proportioning valves, track biased pads, and DOT 4 fluid (or better?).
 

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Jason, what are you basing your experience on? Drilling the solid rotors seems like it would help (if I take them off I might as well switch over to vented rotors though) but I know of atleast 2 Milanos that were fading their brakes this last weekend at the track in very hot weather with stock proportioning valves, track biased pads, and DOT 4 fluid (or better?).
We have done a couple rear drilled and slotted rotors with some success and with basic knowledge of braking it could be effective. If the rotors are prone to fade on the rear, then drilling them to reduce the heat should be effective, of course installing vented would be the best option in my book. Or larger front rotors can calipers.

Without a real brake upgrade they will over heat and fade, they are not going to be able to handle much at stock level especially if they are just throwing race pads in and fluid.
The front rotors are only 22mm thick/269mm in diameter rears are 9.8mm thick/250mm in diameter. That is the weak point. I would say at least 26-32mm thick/289-315mm in diameter would reduce this problem. Brake booster and MC seem to be a pretty good size to handle the larger and thicker rotors.

I just did a big brake upgrade on my 164 for example (12V) version.

Rear brakes not a real problem but the fronts are not the best.
They are also 22m thick/281mm in diameter.
I opted to upgrade the whole brake system from a 24V LS, Calipers, carriers, rotors, brake booster and MC.
Still the same size rotors in diameter but 26mm thick. Brake calipers went from a 54mm piston to a 57mm piston, Brake booster went from 6" in length to 16" in length with a more potent MC. Rears happen to be the same on all cars so no change there.
Drastic drastic difference in braking power. The thickness of the rotor handles the heat better while the other components work together to provide better bite or pressure.

I know this is not a great example but it gets my point across I hope?:D

I think the front to rear rotors are too close in diameter and that a larger front rotor and caliper would probably cure the problem.

I hope that makes sense?

Could also be tire wheels combo as well.

To properly design the right system:
1.Weigh the four corners of the car
2. Design the front and rear brake components to deliver torque in the same ratio as the front-to-rear weight distribution

Modifying your car for the street or for the track, be aware that changes in the braking system as well as changes in the car’s ride height, weight distribution, or physical dimensions can swing brake bias all over the place.
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Factors that will increase front bias------------Factors that will increase rear bias
Increased front rotor diameter------------------Increased rear rotor diameter
Increased front brake pad coefficient of friction----Increased rear brake pad coefficient of friction
Increased front caliper piston diameter(s)---Increased rear caliper piston diameter(s)
Decreased rear rotor diameter------------------Decreased front rotor diameter
Decreased rear brake pad coefficient of friction----Decreased front brake pad coefficient of friction
Decreased rear caliper piston diameter(s)----Decreased front caliper piston diameter(s)
Lower center of gravity----------------------Higher center of gravity
More weight on rear axle--------------------Less weight on rear axle
Less weight on front axle--------------------More weight on front axle
Less sticky tires (lower deceleration limit)--------More sticky tires (higher deceleration limit)
---------
As far as fluid is concerned Once the fluid over heats it is done, so the fade they experienced may be caused but 1 overheating as you mention and 2 the fluid overheating past it's boiling point then rendered useless thus promoting fade under extreme conditions. Improper race pad and rotor break in would cause this issues as well. If they are not seated correctly for race purposes they can experience lots of fade under extreme conditions.

Fluid I always recommend is ATE super Blue or ATE gold, same thing just ones blue and the other, well it's gold.

There could be many many issues contributing to the fading. Pads and fluids won't cure a improper brake system and improper brake in process for race pads.

You can get good results from the stock system if they are seated correctly.
Try turning the rotors and braking in the rotors correctly for maximum performance.
Just my advice.
Jason
 

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Pads and fluid make a big difference, but it isn't enough. On my Verde I was getting air from both the front and the rear lines so I think both ends should be upgraded. I have to say though, that this was in the worst case scnario : 107 degree temps and a very short and brake intensive little track. I didn't have problems with the brakes at a larger track and about 85 degree weather. The Milano and GTV6 are weaker than they should be in the rear because the exhaust runs next to one of the rear calipers (being moutned inboard) but without a pyrometer, I won't know which end to deal with first.

But anyways, for track use I don't think increasing the rear braking is worthwhile on a stock system. Never know until I try it though. I'll post on this thread eventually with my results after installing an adjustable valve.
 

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Pads and fluid make a big difference, but it isn't enough. ... The Milano and GTV6 are weaker than they should be in the rear because the exhaust runs next to one of the rear calipers (being moutned inboard) but without a pyrometer, I won't know which end to deal with first.
Surely you jest. I didn't have brake problems, although I did have Porterfield R4's and not the R-4S' pads. And you saw what kind of POS I had for a car last weekend :p. That car has had no love throughout its life and still the brakes did just fine over and over again .... I'm thinkin' driver improvement! :D

BTW - you should start with a new ABS pump and accumulator, and do what Lalo did - put them out of the direct path of radiant heat (e.g. manifolds and radiator fan wash).

Oh, back on thread; everyone's car setup is different and frequently it should match the driver's driving style. On a stock car, I think the bias is just fine but that's one man's opinion, and I've made it work for me for a looooooong time. I didn't have to increase the rear bias until I swapped out to four-piston Brembos in the front.
 

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Nizam,

I'm pretty sure 75evo faded once, and I faded twice. My car is full weight minus 30lb rear seats. 75evo's car is quite a bit lighter than my street car (no headliner, ABS, bumpers, other missing stuff!) and your car is a shell on wheels with a cage. And you forgot to mention your Hoosiers!

First run, I FADED the brakes and my pump was cavitating. Day two I was only having cavitation problems. I think you'll agree that the two problems show up differently (fluid too hot = spongy brakes, ABS pump cavitating = NO brakes.) The pump will eventually cool and give me brake pressue again. If I fade them, that's it - no more brakes until I bleed. It's pretty obvious to me which problem I'm dealing with.

Also, April showed me how to brake efficiently in a Milano. Driver error should be less of a factor than usual.

Offtopic! - - Thunderhill is only 3 hours away and supposedly VERY techical and fun. I'll talk to you about having a Milano day up there in the future.
 
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