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      05-27-2011, 03:41 AM   #23
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^ Thanks for the informative post!

Yeah, a friend of mine living in Canada says that ST60s and ST40s have annoying kickback when he's tracking. When I told him that I was possibly looking into StopTech BBKs as my 4th or 5th choice on the BBK priority list, he warned me about this very issue. Says that I need to pay attention and pump the brakes every now and then to make sure I don't get on the brakes and have nothing there
The odd thing is, he called StopTech and complained about the issue. They just claimed that it's not something that's supposed to happen
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      05-27-2011, 06:23 AM   #24
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Quote:
Originally Posted by mfanatic325 View Post
^ Thanks for the informative post!

Yeah, a friend of mine living in Canada says that ST60s and ST40s have annoying kickback when he's tracking. When I told him that I was possibly looking into StopTech BBKs as my 4th or 5th choice on the BBK priority list, he warned me about this very issue. Says that I need to pay attention and pump the brakes every now and then to make sure I don't get on the brakes and have nothing there
The odd thing is, he called StopTech and complained about the issue. They just claimed that it's not something that's supposed to happen
I can tell you with certainty that I've never had kick back issues with my Stoptechs and heavy braking on NT01s and DTC70s (Hawks pretty much full race pad), that being said I haven't run them on full Hoosiers yet, but will in the near future and don't anticipate the only problem. The only issue I have had since going to track pads was a slight shimmy in the rear under super hard braking, which has turned out to be my RTABs. When you get to that point everything pretty much needs to be gone through with spherical bearings or solid mounts as the suspension "give" can't be confused with the tires slip angles when driving a full slick.
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      05-27-2011, 06:23 AM   #25
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+1 great info coming together here.
This is the first I've heard about a kickback issue.
It would be great if more members running BBKs would chime in on this.

One thing that comes to mind is our pad drying system.
I wonder if that could somehow be triggered for track use?
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      05-27-2011, 10:50 AM   #26
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Quote:
Originally Posted by inTgr8r View Post
+1 great info coming together here.
Yeah, most of the threads I start aren't very helpful...
hahaha jk. That's obviously false
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      05-27-2011, 11:17 AM   #27
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Pad drying only activates when wipers are active.
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      05-27-2011, 11:19 AM   #28
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hmm, never knew we had that feature
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      05-27-2011, 11:24 AM   #29
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Knock back springs should cure the issue.

I'm not sure if Stoptech includes these with there calipers or not, however
AP /Brembo / PFC have this option with there race calipers. You can even
order them with different spring rates.

Hope this helps...

Last edited by BookerM3; 05-27-2011 at 04:11 PM..
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      05-27-2011, 12:09 PM   #30
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Subscribed. So much knowledge.
Will re-read this as my experience goes up and up.
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      05-27-2011, 06:08 PM   #31
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Knockback is pretty bad with my Stoptechs, only started happening when the handling capability of the car was much better than stock. TCKline DA suspension, PSC tires, etc. I really don't think it should happening but two shops have looked at it and said everything is fine. Stoptech said I could try the kick back springs but they said it will be annoying for daily driving. Anyone with any ideas?
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      05-27-2011, 06:20 PM   #32
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Quote:
they said it will be annoying for daily driving.
In what way?
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      05-27-2011, 07:20 PM   #33
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Quote:
Originally Posted by inTgr8r View Post
In what way?
Springs basically are always pushing the pistons back towards the rotors, so depending on how strong (for lack of a better word) the springs are, you always going to have a bit of braking going on.
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      05-28-2011, 01:00 AM   #34
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Quote:
Originally Posted by onelove View Post
I can tell you with certainty that I've never had kick back issues with my Stoptechs and heavy braking on NT01s and DTC70s (Hawks pretty much full race pad), that being said I haven't run them on full Hoosiers yet, but will in the near future and don't anticipate the only problem. The only issue I have had since going to track pads was a slight shimmy in the rear under super hard braking, which has turned out to be my RTABs. When you get to that point everything pretty much needs to be gone through with spherical bearings or solid mounts as the suspension "give" can't be confused with the tires slip angles when driving a full slick.
That is good news for the flex in the Z4 hub.

We did not experience it on Nittos, we only had the issue on Slicks or Hoosiers. With them G's, something will give on a stock car.

The C6 OEM caliper was a pain with the padlets (3 per caliper). GM was aware of the flex and when we swapped back to padlets, the issues went away. At the time no one made a decent race pad for the C6 Z06. Thus simplify, or so we thought, with Stoptech or a BBK.

Don't get me wrong, I don't think Stoptech is the issue, I think ANY Monblock style is the issue. I have very high regard for the Stoptech product and use it on other cars. They do their home work on bias and max the OEM master and prop valves. Brembo had the better true floating rotor design at that time. that should help some with kick back. But some systems use an adjustable prop valve, not so good for a driver/tracker car.

If the Z4 does not get the same level of flex , then we are good. I just don't know. The poster quoted here, has a real world level of experience with them on a car running Nitto's. If that is what you run, it sounds like good advice.

If you are going to be more aggressive, it seams to me, with far more M3's running a similar spindle , hub and caliper, we can make a few assumptions when it comes to our cars. Just saying I would do my homework.

The best advise I can give is too let a real Pro drive the car. If you can't beat or match their times, more seat time is required. Period.

IMO Trying to replace skill with parts is a bit of a losing battle. Seat time is king. I know crap 70's Alpha's or 95-08 M3's with good drivers that will out run R8's and Stradale's , Zo6's and Ford GT's. Sure you can buy your way around some cars. But what fun is that?

Honestly, nothing feels better than to wax a car with with twice the HP 22 Tracks days is about the same $'s as a BBK. Or go to a really good school. Personally I like Spring Mtn in Pahrump Nevada. Great training track and you will come back 4-10 secs faster depending on your current level. Tell Dave and Victor what you want to achieve.
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      05-28-2011, 12:16 PM   #35
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Quote:
Originally Posted by Shereef_Osman View Post
Knockback is pretty bad with my Stoptechs, only started happening when the handling capability of the car was much better than stock. TCKline DA suspension, PSC tires, etc. I really don't think it should happening but two shops have looked at it and said everything is fine. Stoptech said I could try the kick back springs but they said it will be annoying for daily driving. Anyone with any ideas?
You were the friend I was referring to with the knockback issues

Cobra, I'm pretty sure a pro driver can get really close to, if not beat 1:40 with my car currently as-is; without upgrading brakes or tires or anything.
That pretty much puts me at around 7 seconds slower
I've not a doubt in my mind that I need more seat time
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      05-28-2011, 02:22 PM   #36
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I'm going to have to break this to you. It is going to get progressively HARDER to drop time as you get faster. Soon you will be counting 10th and 100th as big improvements. Don't be surprised if you NEVER got to the 1:40.

http://www.fastestlaps.com/tracks/laguna_seca.html

The Audi R8 in a professional's hand couldn't break 1:40.
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      05-29-2011, 07:14 PM   #37
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haha good game....

But you know, I find that some of these are kind of off.
For example, #35 Porsche 997 Carrera S. How could that only run 1:50?
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      05-29-2011, 07:30 PM   #38
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With all do respect... Most of us here do not need BBK's to get our times down at our local tracks. The OE brakes, with an upgraded friction material will suffice for the majority. BBK's look sweet however!
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      05-30-2011, 02:05 AM   #39
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Quote:
Originally Posted by The HACK View Post
I'm going to have to break this to you. It is going to get progressively HARDER to drop time as you get faster. Soon you will be counting 10th and 100th as big improvements. Don't be surprised if you NEVER got to the 1:40.

http://www.fastestlaps.com/tracks/laguna_seca.html

The Audi R8 in a professional's hand couldn't break 1:40.
Steve Millen a 1:53 in a C5Z in the wet, that is seriously not his best work if I could get around him in the dry on kind of tires. But a boost for my ego in any case. LOL
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      05-30-2011, 08:32 AM   #40
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I would suggest to upgrade the lines as well

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      05-30-2011, 11:35 AM   #41
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Very true - the SS lines sure improved my pedal feel!
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      05-30-2011, 12:26 PM   #42
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Quote:
Originally Posted by mfanatic325 View Post
haha good game....

But you know, I find that some of these are kind of off.
For example, #35 Porsche 997 Carrera S. How could that only run 1:50?
That time was logged in '04? It's probably a typo and it's a 996 Carrera S.

Also, a long time ago I interviewed Bill Auberlen after a race at Laguna Seca, and "off the record" he said that Laguna Seca seems to favor BMWs in terms of set-up. This was a race where he had beaten a couple of Mustang GTs for a win in GS and the closest Porsche was 3 or 4 positions back of him...

Lastly, comparing lap times driven by pros...Something about Princess Leia...yeah.

Just sayin' that dropping SECONDS off of your lap time isn't as easy as it seems on Gran Turismo. IF your goal really is a time in the 1:40s? The first tool you need to invest in is a data acquisition unit, not big brakes.
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      05-30-2011, 07:20 PM   #43
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Quote:
Originally Posted by CobraR1339 View Post
Steve Millen a 1:53 in a C5Z in the wet, that is seriously not his best work if I could get around him in the dry on kind of tires. But a boost for my ego in any case. LOL
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      05-30-2011, 08:24 PM   #44
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Quote:
Originally Posted by The HACK View Post
first tool you need to invest in is a data acquisition unit, not big brakes.
I 100% agree with this statement, my Traqmate was one of the best investments I've made. Especially as you get closer to your ideal time, finding a nut who is willing to sit in the passenger seat while you hammer at 10/10th is much more difficult, most pros prefer data coaching. Coaching is another investment I've found to be worht it's weight in gold, both pro and senior driver/free coaching.
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