I thought I'd take the opportunity to share our Fulvia's latest road adventure and to solicit some brake advice.
Last weekend, we did the tenth California Melee, a ~850 mile tour for pre-1975 cars. The event had around 60 cars, primarily Alfas, MGs, Triumphs and Fiats, but including such rarities (for California, at least) as a Citroen Light 15, a Mangusta, and an NSU Sports Prinz. We had the only Lancia.
The route used mostly secondary roads (chosen for driving fun and scenic value rather than quickest-way-there) and included a number of dirt/gravel sections.
The trip confirmed my opinion about what a great, well-balanced all-rounder the Fulvia is. Nimble enough to keep up with bigger engined stuff in the twisties, comfortable enough that I could actually still stand and walk at the end of a long day, and roomy enough for my Navigator to have packed her entire wardrobe.
The car handled three days of very spirited driving without drama or complaint. The only issue I encountered was some discernable brake fade during long downhill stretches in the mountains. The brakes are newly rebuilt, so I'm interested in hearing what kind of brake pads other Series One owners use for driving like this (e.g. fast road, rather than competition).
Some of our snaps from the event are at: http://www.fulviacam.phanfare.com/
Much better pictures, by another participant, are at: http://craig.howell.net/06californiamelee/
Info about the Melee itself, including contact info, is at: http://www.californiamelee.com/
Regards
Shaun Pond
67 Lancia Fulvia Coupe Rallye 1.3
California Melee X
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Huib
Re: California Melee X
Do you think it was the pads or the fluid starting to boil?
Although the manual specifies DOT3 bake fluid, I use DOT4 without any problems. The manual also says to change it every two years. This is important.
At the time of the Dunlop brakes the philosophy was to insulate the heat from the fluid. This explains the form of the relatively thick pads with rather small cross section. This worked rather well with the old pads containing asbestos. When asbestos was banned we suffered many years from low quality pads for the Dunlop brakes. Modern materials don't work well in those brakes. Most pads on the market are made from asbestos free material not capable of doing a proper job. It is only since a very few years that Mintex is able to make asbestos free friction material equalling the old high quality pads like the Mintex M69FF or M58FG in all aspects including thermal insulation. It requires an order of 4000 pcs to have them make the pads. I combinded orders with some friends some years ago and have plenty at 45 euro per axle set.
Note that the thickness of the pads is divided in three functional sections.
1) a section of a few mm that sticks in the calliper.
2) a section to bridge the gap between calliper and disc
3) a section to allow wear
The minimum of 1 and 2 combined is 8mm, about half the thickness of a new pad. The calliper has to be centered on the disc using shims.
Pads wear depends very much on the way of driving. In a flat country like Holland the pads at the front last about 30.000km during normal road use.
Since the total of the sections 1, 2 and 3 provide the thermal insulation it is a good idea to make sure the thickness is nearer the 17mm when new than the 8mm end of life thickness when going for a fast mountain trip.
Although the manual specifies DOT3 bake fluid, I use DOT4 without any problems. The manual also says to change it every two years. This is important.
At the time of the Dunlop brakes the philosophy was to insulate the heat from the fluid. This explains the form of the relatively thick pads with rather small cross section. This worked rather well with the old pads containing asbestos. When asbestos was banned we suffered many years from low quality pads for the Dunlop brakes. Modern materials don't work well in those brakes. Most pads on the market are made from asbestos free material not capable of doing a proper job. It is only since a very few years that Mintex is able to make asbestos free friction material equalling the old high quality pads like the Mintex M69FF or M58FG in all aspects including thermal insulation. It requires an order of 4000 pcs to have them make the pads. I combinded orders with some friends some years ago and have plenty at 45 euro per axle set.
Note that the thickness of the pads is divided in three functional sections.
1) a section of a few mm that sticks in the calliper.
2) a section to bridge the gap between calliper and disc
3) a section to allow wear
The minimum of 1 and 2 combined is 8mm, about half the thickness of a new pad. The calliper has to be centered on the disc using shims.
Pads wear depends very much on the way of driving. In a flat country like Holland the pads at the front last about 30.000km during normal road use.
Since the total of the sections 1, 2 and 3 provide the thermal insulation it is a good idea to make sure the thickness is nearer the 17mm when new than the 8mm end of life thickness when going for a fast mountain trip.
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shaun pond
Re: California Melee X
Huib, thanks.
I'd never thought about the design philosophy behind disc brakes before; the thick pad/small cross section being intentional rather than the result of space contraints. Very interesting.
I'm not sure whether it was the pads or the fluid, but am inclined to suspect the fluid, as the pads were brand new, full thickness pieces on newly rebuilt calipers and master cylinder. The fluid was also new.
Do you know if there is a discernable performance difference between DOT3 and DOT4 fluids, in terms of boiling point?
Regards
I'd never thought about the design philosophy behind disc brakes before; the thick pad/small cross section being intentional rather than the result of space contraints. Very interesting.
I'm not sure whether it was the pads or the fluid, but am inclined to suspect the fluid, as the pads were brand new, full thickness pieces on newly rebuilt calipers and master cylinder. The fluid was also new.
Do you know if there is a discernable performance difference between DOT3 and DOT4 fluids, in terms of boiling point?
Regards
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Neil
Re: California Melee X
Shaun,
I found this table in an article a while back which shows the various boiling points of brake fluid, both dry and wet, wet boiing points are much lower than fresh dry fluids, I hope this helps.
Fluid type Dry Boiling Point Wet Boiling Point
DOT 3 401 F (205 C) 284 F (140 C)
DOT 4 446 F (230 C) 311 F (155 C)
DOT 5 500 F (260 C) 356 F (180 C)
DOT 5.1 518 F (270 C) 375 F (191 C)
"What is the difference between DOT3, DOT4, DOT5 and DOT5.1 brake fluids?
DOT 3, DOT 4 and DOT 5.1 brake fluids are glycol based compounds that are compatible with one another. DOT 5 brake fluid is silicone based and should never be mixed with DOT 3, DOT 4 or DOT5.1. DOT 3, DOT 4 and DOT 5.1 fluids may damage painted surfaces and DOT 3 and DOT 4 have lower boiling temperatures than DOT 5 (DOT 5.1 has the same boiling point as DOT 5).
Furthermore, DOT 3, DOT 4 and DOT 5.1 fluids are "hygroscopic", which means they absorb moisture from the air. This causes the fluid to turn dark, indicating that it is time for the brake fluid to be replaced. DOT 5 fluid will not damage paint, has a boiling temperature in excess of 500f F, and is not hygroscopic."
Regards,
Neil
I found this table in an article a while back which shows the various boiling points of brake fluid, both dry and wet, wet boiing points are much lower than fresh dry fluids, I hope this helps.
Fluid type Dry Boiling Point Wet Boiling Point
DOT 3 401 F (205 C) 284 F (140 C)
DOT 4 446 F (230 C) 311 F (155 C)
DOT 5 500 F (260 C) 356 F (180 C)
DOT 5.1 518 F (270 C) 375 F (191 C)
"What is the difference between DOT3, DOT4, DOT5 and DOT5.1 brake fluids?
DOT 3, DOT 4 and DOT 5.1 brake fluids are glycol based compounds that are compatible with one another. DOT 5 brake fluid is silicone based and should never be mixed with DOT 3, DOT 4 or DOT5.1. DOT 3, DOT 4 and DOT 5.1 fluids may damage painted surfaces and DOT 3 and DOT 4 have lower boiling temperatures than DOT 5 (DOT 5.1 has the same boiling point as DOT 5).
Furthermore, DOT 3, DOT 4 and DOT 5.1 fluids are "hygroscopic", which means they absorb moisture from the air. This causes the fluid to turn dark, indicating that it is time for the brake fluid to be replaced. DOT 5 fluid will not damage paint, has a boiling temperature in excess of 500f F, and is not hygroscopic."
Regards,
Neil
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shaun pond
brake fluid
Neil, thanks!
Interesting table! I had no idea that there was such a difference (e.g. 55 C between DOT3 and DOT5, "dry") between the different types of fluid. Must check to see what sort is in my car.
I'm not sure what the table means by "dry" and "wet" boiling points. Does "dry" refer to the brake fluid in situ in the system in the car? And "wet" mean tested while exposed to the atmosphere, as if I were to boil some up on the stove to accompany my eggs in the morning? Or something else?
Last, have people successfully used DOT5.1 (silicone based fluid) in their Fulvias? I seem to remember it NOT being recommended for some older British cars, like my Austin Healey, due to concerns about compatibility with the rubber bits, but I don't know if the same objection applies to Lancias.
Thanks again!
Interesting table! I had no idea that there was such a difference (e.g. 55 C between DOT3 and DOT5, "dry") between the different types of fluid. Must check to see what sort is in my car.
I'm not sure what the table means by "dry" and "wet" boiling points. Does "dry" refer to the brake fluid in situ in the system in the car? And "wet" mean tested while exposed to the atmosphere, as if I were to boil some up on the stove to accompany my eggs in the morning? Or something else?
Last, have people successfully used DOT5.1 (silicone based fluid) in their Fulvias? I seem to remember it NOT being recommended for some older British cars, like my Austin Healey, due to concerns about compatibility with the rubber bits, but I don't know if the same objection applies to Lancias.
Thanks again!
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Huib
Re: California Melee X
Very useful table, Neil.
I do sometimes think that the normal brake fluid is hygroscopic on purpose. Any water molecules are dispersed through the fluid and cannot freeze.
In the silicone fluid water molecules cluster together to form droplets, which can freeze.
I do sometimes think that the normal brake fluid is hygroscopic on purpose. Any water molecules are dispersed through the fluid and cannot freeze.
In the silicone fluid water molecules cluster together to form droplets, which can freeze.
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Huib
Re: brake fluid
Good DOT4 should be able to do the job. If not, there might be something else.
Years ago I had the policy to use British pads (Mintex) and British brake fluid because the Dunlop brakes are British. I figured this was the smart thing to do as the engineers all went to the same schools and worked from compatible philosophies.
Today we don't know where the rubber parts come from and design philosophies are more global anyway. I still stick with Mintex pads but for the brake fluid I just buy the low cost DOT4 from the shop on the corner. I have no problems.
Another point to consider before changing to fluids with higher boiling points is the thermal expansion of pistons and cilinders. The boiling point is the highest temperature the system can reach. Because if the fluid boils braking ceases and no more heat is added..
I measured pistons (the 2 1/4" ones at the front) and cilinders at 20 C and at 200 C. The pistons had expanded correctly at the thermal expansion rate of cast iron. I fully expected the cilinders to have done the same as I had learned at school. However they had not expanded. When researching it I found that this does happen with things like cilinders and bushes. When the (unpredictable) ratio between wall thickness and diameter gets below a certain value the cilinder does not expand but the wall itself expands inwards and outwards. The expansion is very small because the wall is very thin. The cilinder thus keeps the same diameter.
In any case you have to check that the higher temperature does not cause the piston to seize in the cilinder. Generally the clearance between piston and cilinders (at the front) is about 0,2 mm. If it is 0,3 mm or higher it is a reject as leaking may occur.
The pistons at the rear are made from brass. Brass has a thermal expansion which is about twice as high as cast iron. This gives no problem as the pistons are small and the walls of the cilinders are much thicker which causes the cilinders to expand themselves.
At the very beginning Dunlop also used brass for the 2 1/8" pistons at the front. They quickly changed to cast iron. I don't know the exact reason, but they might have been bitten by the thermal expansion thing.
Also remember that heat transfer (cooling) is proportional to the temperature difference. The higher the temperature of the brakes the faster they cool. If you come into a situation like fast down hill driving where overheating is a risk, it is a good idea to change to short hard braking instead of soft long braking. When braking hard the temperature rises quickly which results in better cooling. Also the time between braking is longer so they have more time to cool.
Years ago I had the policy to use British pads (Mintex) and British brake fluid because the Dunlop brakes are British. I figured this was the smart thing to do as the engineers all went to the same schools and worked from compatible philosophies.
Today we don't know where the rubber parts come from and design philosophies are more global anyway. I still stick with Mintex pads but for the brake fluid I just buy the low cost DOT4 from the shop on the corner. I have no problems.
Another point to consider before changing to fluids with higher boiling points is the thermal expansion of pistons and cilinders. The boiling point is the highest temperature the system can reach. Because if the fluid boils braking ceases and no more heat is added..
I measured pistons (the 2 1/4" ones at the front) and cilinders at 20 C and at 200 C. The pistons had expanded correctly at the thermal expansion rate of cast iron. I fully expected the cilinders to have done the same as I had learned at school. However they had not expanded. When researching it I found that this does happen with things like cilinders and bushes. When the (unpredictable) ratio between wall thickness and diameter gets below a certain value the cilinder does not expand but the wall itself expands inwards and outwards. The expansion is very small because the wall is very thin. The cilinder thus keeps the same diameter.
In any case you have to check that the higher temperature does not cause the piston to seize in the cilinder. Generally the clearance between piston and cilinders (at the front) is about 0,2 mm. If it is 0,3 mm or higher it is a reject as leaking may occur.
The pistons at the rear are made from brass. Brass has a thermal expansion which is about twice as high as cast iron. This gives no problem as the pistons are small and the walls of the cilinders are much thicker which causes the cilinders to expand themselves.
At the very beginning Dunlop also used brass for the 2 1/8" pistons at the front. They quickly changed to cast iron. I don't know the exact reason, but they might have been bitten by the thermal expansion thing.
Also remember that heat transfer (cooling) is proportional to the temperature difference. The higher the temperature of the brakes the faster they cool. If you come into a situation like fast down hill driving where overheating is a risk, it is a good idea to change to short hard braking instead of soft long braking. When braking hard the temperature rises quickly which results in better cooling. Also the time between braking is longer so they have more time to cool.
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lucas
Re: California Melee X
Hi Shaun,
I looked at the albums, and the pictures are beautiful.
Only one advise, get rid of those ugly black windscreen wipers, Huib has still a few inox sets for sale.
Much more beautiful and you can buy new inserts for rebuilt after a few years.
Lucas
I looked at the albums, and the pictures are beautiful.
Only one advise, get rid of those ugly black windscreen wipers, Huib has still a few inox sets for sale.
Much more beautiful and you can buy new inserts for rebuilt after a few years.
Lucas
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Huib
Re: California Melee X
I wasn't really prepared to spend time going to the post office with wipers, but since Lucas mentions it, here are some pics.
These are original NOS wipers. The rubber feels ok, but I am not sure how long the old rubber will last. New rubbers can be bought from Trico or others. I also have a few dozen of sets of refills
These are original NOS wipers. The rubber feels ok, but I am not sure how long the old rubber will last. New rubbers can be bought from Trico or others. I also have a few dozen of sets of refills
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Peter de Wit
brake fade
Shaun, about your brakes fading: I have been there. I use S2 brakes, with the similar problem that you have with your Dunlops: there are no good modern replacements. Only old boxes with junk. For me it was not uncommon to fit new brake pads brake them in. Do the ultimate test run and have them fade on FLAT roads in a couple of minutes. Get them out, throw them away and try a new set. Some proved to be really bad!! I now use competition pads (not recommended for road use) and they brake as they should. But still, I never managed to get the brake fluid to boil. And I have experienced that many times with racing alfa's. I know the scary feeling! Never experienced or heard of that with fulvia's.
EBC has dunlop pads in their catalogue. Called green stuff for 'fast road'. Not too fast or you have the same problem. But at least they are modern. If they are no good, go for yellow stuff and you are cured. Or easier to do, take your old brake pads and let them glue modern compound stuff on your old metal backplate. This is what I did with my first good brakes. 100eur per set and very, very good. Yellow stuffs are around 180 I believe.
EBC has dunlop pads in their catalogue. Called green stuff for 'fast road'. Not too fast or you have the same problem. But at least they are modern. If they are no good, go for yellow stuff and you are cured. Or easier to do, take your old brake pads and let them glue modern compound stuff on your old metal backplate. This is what I did with my first good brakes. 100eur per set and very, very good. Yellow stuffs are around 180 I believe.