Braking Bias effects on a Road Race Car
#32
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If the sun is revolving around the moon while the deer breasts lay in the lillies, does popcorn pop in a vaccum? What if the vacuum is a Hoover? If no one is around to see the popcorn pop, does it really pop? Choices: A or B
#33
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thanks Ken and Bryan.
Im getting excited to see what happens. Ill probably do some testing at sears, as too much rear brakes at sears can be a problem.
mk
Im getting excited to see what happens. Ill probably do some testing at sears, as too much rear brakes at sears can be a problem.
mk
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Like Larry, in my 911 I trail brake into most of the corners at a given track. However, with the Cup (at least so far) I find that I can't drive the same line/style because I get rear lock and just generally less stablity when trying to turn and brake. It's not the geometry of the car because obviously the cup car is superior but I would actually dial OUT some rear in the Cup if I could. I know it would be faster for the way I DRIVE. However, since I can't do that, I'm having to adjust my driving style to fit the set-up.
#35
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You know how many race laps i have had with this chassis. get rid of the 33 bar and put in the 11 for awhile. (I have the low one. I think its 11bar if 33 is the higher one). Its not going to be much, if the fronts are about 5-10times more the stopping power anyway. I wonder what the G loading is for our cars on a reasonably hot lap. Im betting near 2 Gs braking. Ill have to review Rylans telemetry output to see what ball park we are in. If its near 2g's, there is not much braking done by the rears. maybe only a little to help stablize the car and add a little "Squat" as Seth has pointed out.
mk
mk
I thought stock was 17? I don't even have a stock one...just the one thats in there? All I know is the brakes seem to work just fine! So much so that I find myself having to tighten up the harness more and more as I use more of the brakes.....didn't have that problem in the street cars!
Remember Anderson took the bias bar OUT when he put the big brakes on the front!!! So he gets the same pressure all around!!! Seems crazy, but clearly his brakes work just fine....
#37
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Like I said, i dont know the bar level, but mine is stock for an 86.
Anderson really runs full pressure to the rears? I guess he can do that when he runs the F50 , 14" rotors up front.![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
what ever i have for the rear, im going to turn it up. its got to be too light, as i havent changed my rear pads in over 50 race days!
mk
Anderson really runs full pressure to the rears? I guess he can do that when he runs the F50 , 14" rotors up front.
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what ever i have for the rear, im going to turn it up. its got to be too light, as i havent changed my rear pads in over 50 race days!
mk
MK
I thought stock was 17? I don't even have a stock one...just the one thats in there? All I know is the brakes seem to work just fine! So much so that I find myself having to tighten up the harness more and more as I use more of the brakes.....didn't have that problem in the street cars!
Remember Anderson took the bias bar OUT when he put the big brakes on the front!!! So he gets the same pressure all around!!! Seems crazy, but clearly his brakes work just fine....
I thought stock was 17? I don't even have a stock one...just the one thats in there? All I know is the brakes seem to work just fine! So much so that I find myself having to tighten up the harness more and more as I use more of the brakes.....didn't have that problem in the street cars!
Remember Anderson took the bias bar OUT when he put the big brakes on the front!!! So he gets the same pressure all around!!! Seems crazy, but clearly his brakes work just fine....
#38
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Did the driver got his foot hung on the throttle a bit at around the same point he hit his maximum braking G's? What's the purple line at the bottom of the plot?
Last edited by Bryan Watts; 03-17-2009 at 09:19 PM.
#39
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Yeah it is my car. 993 RSR w/o significant downforce (has some though, normal big wing and splitter). It stops well because it is light, draggy, ***-heavy, and has big front tires compared to a 996/997 Cup car. It also has very effective ABS.
My foot (size 14) is kinda big so often I have a little throttle on during braking. I know it isn't good.
The purple line is brake pressure in bar. It tapers off after the initial hit because I braked too early, as I always do.
This is braking for 10a at Road Atlanta. The downhill is adding to the negative long G a little bit. I think the pavement is really good there. I usually cannot get over about 1.65G under braking.
Chris Cervelli
Spline Technologies
My foot (size 14) is kinda big so often I have a little throttle on during braking. I know it isn't good.
The purple line is brake pressure in bar. It tapers off after the initial hit because I braked too early, as I always do.
This is braking for 10a at Road Atlanta. The downhill is adding to the negative long G a little bit. I think the pavement is really good there. I usually cannot get over about 1.65G under braking.
Chris Cervelli
Spline Technologies
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I don't have any data saved on my work laptop...makes me anxious to see what sort of braking G's we're hitting at 10A as compared to flatter braking zones at other tracks.
For what it's worth, the left side of the track at T10 is even grippier and less bumpy than the right. But you can really only use it in the wet because it blows your 10A entry in the dry. I love the 10A/B complex for some reason...one of my favorite turns on any track when I'm going through there well.
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I would see 1.3~1.4 on my RSA with 993TT brakes and Hoosiers. I used a G2X data logger.
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Larry Herman
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Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
#45
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Hahahaha! If only we were allowed one. Actually, truth be told, that car SUCKED in braking, until we went to PFC01's at the Glen. Then, I could brake at just before the 100 marker, and the car was perfect.
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