I think you'll like this, lots of pictures
10-15-2003, 07:53 PM
#11
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Carroll Smith's white paper on monoblock vs two piece.
Two piece steel reinforced calipers were actually introduced AFTER monoblock to stop the darn things from flexing 
quote: "The current generation of Monobloc after market calipers from the reputable manufacturers are at best only about as stiff as conventional two piece units - at ambient temperatures."<ul><li><a href="http://www.stoptech.com/whitepapers/monobloc3.htm">Read it here.</a></li></ul>
quote: "The current generation of Monobloc after market calipers from the reputable manufacturers are at best only about as stiff as conventional two piece units - at ambient temperatures."<ul><li><a href="http://www.stoptech.com/whitepapers/monobloc3.htm">Read it here.</a></li></ul>
10-15-2003, 10:02 PM
#13
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I've seen that article, ...
but he never addresses the issue of the cross section of bolts versus bridge area. I do agree that the stiffest caliper could be a monobloc composite aluminum caliper reinforced with steel bolts, though I need to think about the effect of the different coefficient of thermal expansion of the two materials.
There's marketing hype everywhere, but all 2-piece (or monobloc) calipers are not the same. Also, note that the Carroll Smith white paper is on a site that only sells a 2-piece caliper.
On the other side of the coin, look at a brake supplier like <A HREF="http://www.hrpworld.com/index.cfm">Hoerr Racing</a>. It's hard to believe that you can get the 2-piece 4-pot Alcon Type B calipers that's stiffer than the monobloc 4-pot Alcon TA-4 at almost twice the price. [or at set of Alcon Enduro 6P calipers at 4x the price] You see similar price difference at Hoerr when you compare Brembo 2-piece and monobloc calipers. Are they really getting away with that much marketing hype? I quess anything's possible.
In the end, only 3rd party testing of caliper stiffness can answer the question.
There's marketing hype everywhere, but all 2-piece (or monobloc) calipers are not the same. Also, note that the Carroll Smith white paper is on a site that only sells a 2-piece caliper.
On the other side of the coin, look at a brake supplier like <A HREF="http://www.hrpworld.com/index.cfm">Hoerr Racing</a>. It's hard to believe that you can get the 2-piece 4-pot Alcon Type B calipers that's stiffer than the monobloc 4-pot Alcon TA-4 at almost twice the price. [or at set of Alcon Enduro 6P calipers at 4x the price] You see similar price difference at Hoerr when you compare Brembo 2-piece and monobloc calipers. Are they really getting away with that much marketing hype? I quess anything's possible.
In the end, only 3rd party testing of caliper stiffness can answer the question.
10-16-2003, 01:00 AM
#14
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its worth noting
that another way of getting the fit would be to use the s8 strut, then the brembo will bolt straight on (just like the s8 2-piece brembo unit) - although i'm not sure of whether you would require the bira hat as well.
10-16-2003, 05:05 AM
#15
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312x25 mm, probably ...
According to AudiWorld's historical <A HREF="https://www.audiworld.com/model/historical.html">Model Guide</a>, 312x?? mm.
According to the Bentley, the 312 mm rotor is 25 mm thick.
According to the Bentley, the 312 mm rotor is 25 mm thick.
10-16-2003, 05:38 AM
#16
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Totally agree ..
that StopTech sells two piece solutions, so advice regarding two piece calipers should be viewed in that light but I also realize that the guy talking was engineering automobiles for 40 years, working for Shelby American as well as ford corporate.
10-16-2003, 05:42 AM
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Interesting
The Ap caliper on this FW22-4 is a two piece and a quick look through APracings website shows that pretty much all front calipers for the various race series from Nascar to F1 use two piece from calipers. Whether this is by choice or by rule, I don't know.
<img src="http://pictureposter.audiworld.com/38899/f1caliper.jpg">
<img src="http://pictureposter.audiworld.com/38899/cockpit.jpg">
<img src="http://pictureposter.audiworld.com/38899/jpm.jpg">
My 4pot APcalipers (CP2271) now classified under "Rally Historics" are a type of two-piece blank lug.
<img src="http://pictureposter.audiworld.com/38899/f1caliper.jpg">
<img src="http://pictureposter.audiworld.com/38899/cockpit.jpg">
<img src="http://pictureposter.audiworld.com/38899/jpm.jpg">
My 4pot APcalipers (CP2271) now classified under "Rally Historics" are a type of two-piece blank lug.
10-16-2003, 05:51 AM
#19
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I believe the modulus of alum. alloys dances around the same number (for the most part)
The yield stress changes a great deal with various alloys. I think the modulus of alum is like 15X10^6. If my memory serves, don't come across many structural beams made of aluminum.
Steel alloys are similar as well, 29x10^6. +/- a bit.
So...
I'm not sure if it would make a huge difference in deflections, unless a particular alloy was more resistant to temperature softening/strain release.
Steel alloys are similar as well, 29x10^6. +/- a bit.
So...
I'm not sure if it would make a huge difference in deflections, unless a particular alloy was more resistant to temperature softening/strain release.
10-16-2003, 05:53 AM
#20
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No. normal aluminum is 71Gpa, Outlawed alloy from decades ago was 192Gpa. Read article ;)
This is wher monoblock calipers get their mystique .. decades old tech which only multimillion dollar F1 teams could afford.