Anyone with ISF brakes on?
10-27-08, 05:03 PM
#16
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Sounds like a good project for somebody....somebody with deep pockets.
10-27-08, 05:11 PM
#17
Brake upgrades don't do anything useful unless you're putting the car through severe duty, which I usually describe as things like driving on a track, driving down the side of a mountain, or being involved in the chase scene from a Bourne movie. Even then where you're seeing the benefit is in the increased fade resistance and thermal capacity you won't have any use for whatsoever unless you're doing things like making repeated high-speed stops in a short period of time.
For a single normal panic stop from highway speeds your $6000 brakes will stop you in -exactly- the same distance as the stock ones will.
10-29-08, 01:24 PM
#19
For street use any brake upgrade is purely cosmetic.
Brake upgrades don't do anything useful unless you're putting the car through severe duty, which I usually describe as things like driving on a track, driving down the side of a mountain, or being involved in the chase scene from a Bourne movie. Even then where you're seeing the benefit is in the increased fade resistance and thermal capacity you won't have any use for whatsoever unless you're doing things like making repeated high-speed stops in a short period of time.
For a single normal panic stop from highway speeds your $6000 brakes will stop you in -exactly- the same distance as the stock ones will.
Brake upgrades don't do anything useful unless you're putting the car through severe duty, which I usually describe as things like driving on a track, driving down the side of a mountain, or being involved in the chase scene from a Bourne movie. Even then where you're seeing the benefit is in the increased fade resistance and thermal capacity you won't have any use for whatsoever unless you're doing things like making repeated high-speed stops in a short period of time.
For a single normal panic stop from highway speeds your $6000 brakes will stop you in -exactly- the same distance as the stock ones will.
10-29-08, 10:27 PM
#20
Well yeah..the IS250 don't have 4-piston calipers in the fronts..but ultimately it's the stickiness of your tires that will stop your vehicle the quickest..it doesn't matter HOW many pistons your braking system has. Some aftermarket companies create LONGER stopping distances when it comes to panic stops, take the ProjectmU system for the Acura RSX Type-S. The factory system w/ a harder compound brake pad stopped quicker than it, for an extra $3k? get outta here..
10-30-08, 06:00 AM
#21
The brakes don't stop the car, the tires do.
Read the fine print on the F-sport site- the 250 with the better stopping distance had half a dozen -other- upgrades compared to the stock 250, including guess what? tires.
"F Sport equiped IS250 used in stopping distance comparison test was equipped with sway bar kit, shocks, lowering springs, rear member brace, front and rear brake upgrades, 19" wheels, and recommended Michelin Pilot Sport tires"
Guess which item there had nothing to do with the better stopping distance? The brakes.
10-30-08, 09:47 AM
#22
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It's true of any car in the world without some exotic wedge-type braking system.
The brakes don't stop the car, the tires do.
Read the fine print on the F-sport site- the 250 with the better stopping distance had half a dozen -other- upgrades compared to the stock 250, including guess what? tires.
"F Sport equiped IS250 used in stopping distance comparison test was equipped with sway bar kit, shocks, lowering springs, rear member brace, front and rear brake upgrades, 19" wheels, and recommended Michelin Pilot Sport tires"
Guess which item there had nothing to do with the better stopping distance? The brakes.
The brakes don't stop the car, the tires do.
Read the fine print on the F-sport site- the 250 with the better stopping distance had half a dozen -other- upgrades compared to the stock 250, including guess what? tires.
"F Sport equiped IS250 used in stopping distance comparison test was equipped with sway bar kit, shocks, lowering springs, rear member brace, front and rear brake upgrades, 19" wheels, and recommended Michelin Pilot Sport tires"
Guess which item there had nothing to do with the better stopping distance? The brakes.
^^ I will agree with you to some extent... regarding the other accessories installed...
But seriously, what do you think is stopping ALL 4 Tires ????
- Joe Z
10-30-08, 09:49 AM
#23
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No one has done this because they're not bolt-on's. There's some pretty extensive modifications that have to be done to fit the IS-F brakes onto the ISx50. If you want to go BBK you're much better off going with the Brembo GT kit for IS350, or some other kit that's actually made for this car.
Javier
Javier
This Post has been Approved by Joe Z ... LoL....
10-30-08, 12:12 PM
#24
That's the only friction that matters as long as you can engage your ABS system.
There's a reason the mathematical formula for braking distance doesn't include anything related to your brakes. They're not relevant.
Now, for fade resistance if you plan to repeatedly brake from 130 mph in a short period of time, like abusing the car at the track, brake parts can make a huge difference.
But just stopping the car from highway speeds under typical conditions? no difference whatsoever. Brembo and Stoptech'll tell you the same even.
10-30-08, 12:51 PM
#25
It's true of any car in the world without some exotic wedge-type braking system.
The brakes don't stop the car, the tires do.
Read the fine print on the F-sport site- the 250 with the better stopping distance had half a dozen -other- upgrades compared to the stock 250, including guess what? tires.
"F Sport equiped IS250 used in stopping distance comparison test was equipped with sway bar kit, shocks, lowering springs, rear member brace, front and rear brake upgrades, 19" wheels, and recommended Michelin Pilot Sport tires"
Guess which item there had nothing to do with the better stopping distance? The brakes.
The brakes don't stop the car, the tires do.
Read the fine print on the F-sport site- the 250 with the better stopping distance had half a dozen -other- upgrades compared to the stock 250, including guess what? tires.
"F Sport equiped IS250 used in stopping distance comparison test was equipped with sway bar kit, shocks, lowering springs, rear member brace, front and rear brake upgrades, 19" wheels, and recommended Michelin Pilot Sport tires"
Guess which item there had nothing to do with the better stopping distance? The brakes.
But compare a stock IS350 and a stock IS250... all sources site average maximum braking distances is shorter on the IS350 than the IS250 by nearly 8-10ft from 60 and exponentially upward, despite having the same tires and the IS250 is slightly lighter...
10-30-08, 02:00 PM
#26
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Edmunds tested both the IS350 and IS250 and came up with shorter braking for the IS250. If you examine the testing conditions, it should have gone in favor of the IS350 because it was warmer:
IS250:
http://www.edmunds.com/insideline/do...ageId=125281#2
IS350:
http://www.edmunds.com/insideline/do...pageId=64972#3
10-30-08, 02:27 PM
#27
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Full Test: 2006 Lexus IS 350 (Date posted: 07-26-2005 )
Tire Brand: Dunlop
Tire Model: Sport Max
30 - 0 (ft): 30.71
60 - 0 (ft): 123.02
2006 Lexus IS 350 Comparison Test (Date posted: 01-26-2006)
Tire Brand: Dunlop
Tire Model: SP Sport Maxx
Curb Weight (lbs.): 3527
30 - 0 (ft): 30
60 - 0 (ft): 120
Follow-Up Test: 2007 Lexus IS 250 (Date posted: 06-12-2007)
Tire Brand: Bridgestone Potenza RE050
Tire Model: performance
Tire Type: all season
Manufacturer Curb Weight (lb): 3503
30 - 0 (ft): 27
60 - 0 (ft): 113
Car and Driver's results:
2008 Lexus IS350 (December 2007)
Braking, 70–0 mph: 167 ft
Curb weight: 3600 lb
A little excerpt from C&D test of a manual IS250, this jibes with Edmund's comment contrasting the two cars too.
Straight-line performance aside, the IS250 is a pleasure to drive, even more than its big brother. The IS350 weighs 135 more pounds than the 3465-pound IS250, and with extra weight carried over its handsome nose, the 350 understeers more than we'd like. Also, the more powerful car's suspension feels a bit overdamped and overzealous, whereas the 250's feels composed and tight. There's predictable understeer on corner entry, but a midcorner squeeze on the throttle is enough to tighten your line for a precise and pleasant blast to the next corner. For better balance, we'd take the IS250 over the IS350.
Braking, 70-0 mph: 170 ft
Curb weight: 3465 lb
Last edited by CRB; 10-30-08 at 02:37 PM.
10-30-08, 02:30 PM
#28
Yup... different tires, weather, the slope of the road tested on, the friction of the road surface tested on, those can all have an impact.
The brake system components can't though, because the brakes aren't what stop the car.
The reason brembo doesn't even list braking distance data on their website is because they know the things they sell have no impact on it. (says so right in their FAQ)
http://www.buybrakes.com/brembo/faq.html#q6
Where can I find test data on stopping distances?
At the speeds that stopping distance is generally measured from (60 to 70mph), the test is primarily testing the tire's grip on the pavement. As delivered from the manufacturer, nearly all vehicles are able to engage the ABS or lock the wheels at these speeds. Therefore, an increase in braking power will do nothing to stop the vehicle in a shorter distance. For this reason, we do not record stopping distances at this time.
The brake system components can't though, because the brakes aren't what stop the car.
The reason brembo doesn't even list braking distance data on their website is because they know the things they sell have no impact on it. (says so right in their FAQ)
http://www.buybrakes.com/brembo/faq.html#q6
Where can I find test data on stopping distances?
At the speeds that stopping distance is generally measured from (60 to 70mph), the test is primarily testing the tire's grip on the pavement. As delivered from the manufacturer, nearly all vehicles are able to engage the ABS or lock the wheels at these speeds. Therefore, an increase in braking power will do nothing to stop the vehicle in a shorter distance. For this reason, we do not record stopping distances at this time.
Last edited by Kurtz; 10-30-08 at 02:34 PM.
10-30-08, 02:53 PM
#29
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Yup... different tires, weather, the slope of the road tested on, the friction of the road surface tested on, those can all have an impact.
The brake system components can't though, because the brakes aren't what stop the car.
The reason brembo doesn't even list braking distance data on their website is because they know the things they sell have no impact on it. (says so right in their FAQ)
http://www.buybrakes.com/brembo/faq.html#q6
Where can I find test data on stopping distances?
At the speeds that stopping distance is generally measured from (60 to 70mph), the test is primarily testing the tire's grip on the pavement. As delivered from the manufacturer, nearly all vehicles are able to engage the ABS or lock the wheels at these speeds. Therefore, an increase in braking power will do nothing to stop the vehicle in a shorter distance. For this reason, we do not record stopping distances at this time.
The brake system components can't though, because the brakes aren't what stop the car.
The reason brembo doesn't even list braking distance data on their website is because they know the things they sell have no impact on it. (says so right in their FAQ)
http://www.buybrakes.com/brembo/faq.html#q6
Where can I find test data on stopping distances?
At the speeds that stopping distance is generally measured from (60 to 70mph), the test is primarily testing the tire's grip on the pavement. As delivered from the manufacturer, nearly all vehicles are able to engage the ABS or lock the wheels at these speeds. Therefore, an increase in braking power will do nothing to stop the vehicle in a shorter distance. For this reason, we do not record stopping distances at this time.
Here is the article. It is pretty interesting.
10-30-08, 03:28 PM
#30
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That's it.....!!!
I am going home and taking OFF my braking system to save weight...
... then I am going to cut a hole in the floor pan so I can "Flinstone" stop my car..
Sorry I couldn't resist...
***
Q - What kind of Tires slow down a Train??
A1 - The Metal Ones on the rail???
or
A2 - The brake pad on each train wheel?
Visual:
I am going home and taking OFF my braking system to save weight...
... then I am going to cut a hole in the floor pan so I can "Flinstone" stop my car..
Sorry I couldn't resist...
***
Q - What kind of Tires slow down a Train??
A1 - The Metal Ones on the rail???
or
A2 - The brake pad on each train wheel?
Visual:
Last edited by Joe Z; 10-30-08 at 03:48 PM. Reason: typo