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Discussion Starter #1
Ive got to uprate my brakes on my car. I was running out of brakes with the 1300 engine and i now have a 2.0 twin spark [tweeked].I have the 75 brembo calipers on the front can these be adapted for the back? Any advice will be gratefully recieved
 

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What rear pressure limiter are you using? The Alfa's rear brakes shouldn't give you any problems if the system is working OK - even the stock setup is fine for all out racing. Many racers use a Tilton adjustable rear valve; it functions much like the stock one only had an adjustable cut-off pressure.

Also, choosing the right pads dramatically affects brake performance.

Check out the brake threads in "Suspension..."

Robert
 

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Brake issues

Ive got to uprate my brakes on my car. I was running out of brakes with the 1300 engine and i now have a 2.0 twin spark [tweeked].I have the 75 brembo calipers on the front can these be adapted for the back? Any advice will be gratefully recieved
What was happening? Was the pedal going to the floor and you had to pump the pedal in the brake zone, or did you have a good pedal but just had to push very hard?

The pedal going to the floor is caused by boiling the fluid and can be helped by a higher temp racing brake fluid, cooling ducts or larger rotors. Most braking is done by the front tires because of weight transfer to the front. Putting a giant brake system on the rear will do very little to help as the rear tires are unloaded under braking and are limited to the amount of work they can do.
All that being said you should verify they are doing their share (15-20% of the work load) If you have a pressure limiting valve it must be set correctly for proper front to rear brake bias.

If you are pushing the pedal harder and the car is not stopping you are fading the pads. This is easy to remedy by switching to a race pad with a higher MOT (maximum operating temperature)

To learn more go the following website

StopTech : Balanced Brake Upgrades


Bob

1965 RHD GTA Corsa Ex Kwech 1966 Trans-Am and B-Sedan Champion
 

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Discussion Starter #4
Thanks for the advice. I am boiling the fluid. I am running synthetic 5.1 race fluid with EBC yellow pads front and rear. I have also ducted air from the front valence to the front discs and removed the backplates. Basically i think i need vented discs and bigger calipers Is there any of this stuff available in USA seeing as im getting more than 2 dollars to my pound?
 

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Thanks for the advice. I am boiling the fluid. I am running synthetic 5.1 race fluid with EBC yellow pads front and rear. I have also ducted air from the front valence to the front discs and removed the backplates. Basically i think i need vented discs and bigger calipers Is there any of this stuff available in USA seeing as im getting more than 2 dollars to my pound?
Vented front rotors will make a huge difference especially if you take high pressure air and force it into the center of the rotor on the inside. Can you buy vented rotors of the same size as the ones you have? If you can make a smaller lighter brake system work it saves the unsprung weight.

Go to higher boiling point brake fluid as the first step. Going from Motul 5.1 to Motul 6.0 gives you almost a 60 degrees F higher wet boiling point. I am not familiar with the front upgrades available for this platform but would say do this last if you can buy a vented rotor of the same size as the solid rotor.

Hope this helps

Bob

1965 RHD GTA Corsa Ex Kwech 1966 Trans-Am and B-Sedan Champion
 

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Discussion Starter #6
The fluid sounds good i will try that. I dont think you can buy just discs and it will mean spacing out the calipers. I will probably just have to go the whole hog and buy the alfaholics set up. Maybe Father Christmas is watching Ill put it on my list
 

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Tom Sahines makes a vented rotor kit (aluminum hat w/ custom disc) for use with the aluminum Brembos. Alternatively, there are supposedly Audi discs that fit - I think bb member seinista has previously posted on these. This set-up w/ stock rears should give more than adequate braking w/ good pads and fluid for most applications and will be lightyears better than w/ small ATE's in the front.
 

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C'mon guys, we've been running VERY VERY fast Giulias for years here in Holland, Giulia Squadra Bianca, and believe me, I have seen direct competition with a Giulia Vs another. The one with big big AP brakes, vented discs, AP pads etc, the other with standard 2000 discs and 75 Brembo calipers. On Hawk pads. Difference? Zilch! Because yes the AP's brake harder but are almost too much, so that it becomes hard to modulate the brakes, or to 'brake less more' as my instructor taught me. On Dijon Prenois, with lots of cool curves the difference was in the end zero. Loose on some corners, win on others.
Just use a very very good pad. In my experience, that is Hawk, and possibly SBS. Ferodo is good too, but eats your discs. EBC is for really serious racing, total [email protected]
Goodridge lines, fresh MC, tilton balancer, good booster and you are perfectly set up.
Bleed the brakes often, even between sessions.
 

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A lot of alfas have been racing at 10/10ths for decades on the stock alfa discs. Better calipers maybe - look at the outlaws perhaps. But the right fluid and pads really makes all the difference. A good tilton valve is a moderate help - even better would be the dual MC adjustable tilton pedal (separate f/r with adjustable balance bar).

Remember most brake fluids absorb water fast - is England still as rainy as when I was there in the 80's? Change and flush every race! Then go rent the Tom Cruise movie "Days of Thunder" about a NASCAR racer, it's a hokey movie but it makes the point that driving technique dominates EVERYTHING!

Personally, I found the un-boosted brakes easier to modulate in a race than the booster set-up, 'tho even the CAS has recommended the booster since the 60's. Just choose the right MC diameter and pads.

Robert
 

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C'mon guys, we've been running VERY VERY fast Giulias for years here in Holland, Giulia Squadra Bianca, and believe me, I have seen direct competition with a Giulia Vs another. The one with big big AP brakes, vented discs, AP pads etc, the other with standard 2000 discs and 75 Brembo calipers. On Hawk pads. Difference? Zilch! Because yes the AP's brake harder but are almost too much, so that it becomes hard to modulate the brakes, or to 'brake less more' as my instructor taught me. On Dijon Prenois, with lots of cool curves the difference was in the end zero. Loose on some corners, win on others.
Just use a very very good pad. In my experience, that is Hawk, and possibly SBS. Ferodo is good too, but eats your discs. EBC is for really serious racing, total [email protected]
Goodridge lines, fresh MC, tilton balancer, good booster and you are perfectly set up.
Bleed the brakes often, even between sessions.
The thread starter Strippy said he was boiling the fluid so I am taking him at his word.
He may have better tires, a higher mu surface or he could be just a few degrees away from being ok. I do not recommend bigger brakes in these vintage cars. A lot of people get the idea that bigger rotors and calipers shorten their stopping distances which is not the case if you can lock the tires with the stock system. Bigger rotors do increase the heat capacity but at a price. Better tires improve your stopping distances and a brake system with less compliance shortens the time to do effective work---hence stainless steel lines and less flex in the calipers help.

Getting the brake bias right is very important and an overamplified system is very difficult to modulate as Seinista points out.

I recommend all of you read this article to help really understand brake system limitations

StopTech : Balanced Brake Upgrades

Of course there is always the chance that Strippy is just faster and dissipating
more kinetic energy.;)

Bob

1965 RHD GTA Corsa Ex Kwech 1966 Trans-Am and B-Sedan Champion
 

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I have vented front discs for 105's made to fit straight on with the Brembo calipers from 116/119 GTV6 etc., in stock.
PM me for details if you wish.
Vince.
 

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some other stuff: If using 2000 or 1300 calipers, ensure that the pistons are placed correctly. My technical english isn't THAT good, but they have a 'lip' or a 'C' which has to be on the FRONT, or your pad will not seat itself correctly, A reducing effectiveness, and B generating more heat!
Perhaps CanAm Bob knows more and can explain better.
Rik
 

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Squadra ran 15 inch slicks, 200 wide, on 7J wheels, with outputs of around close to 200 horse. Lapping Spa at 2.57.
Alternatively, just give Max a yell!
 
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