Rotor vibration
#31
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
96 ft-lbs.
The Sebro Slotted Rotors are a good option. I personally recommend staying away from the cross drilled rotors as they tend to crack a lot.
If you wanted to upgrade then Giro-Disc would be my recommendation, but as many others have mentioned it is better off to keep it stock until you have more seat time.
The Sebro Slotted Rotors are a good option. I personally recommend staying away from the cross drilled rotors as they tend to crack a lot.
If you wanted to upgrade then Giro-Disc would be my recommendation, but as many others have mentioned it is better off to keep it stock until you have more seat time.
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
i like to go a shade lighter, especially if you are taking them on and off very frequently. 90ft-lbs is perfectly fine for track use.
#32
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
No it isn't and I really hope no one else listens to this bad advice.
Do not under torque your wheels everyone, bring the wheel to the proper torque and prevent any possible harm to yourself or anyone else out there.
Do not under torque your wheels everyone, bring the wheel to the proper torque and prevent any possible harm to yourself or anyone else out there.
#33
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
it's practical advice.
there are many companies that spec 80ft'lbs.
my advice, first off here, is that his warped rotors could be caused by the apes at the shop who use impact guns and then just make sure they are torqued to min spec. that can make one lug near 150ft-lbs and others at the min level of near 90 or 95. that causes rotor warping and thats a problem. my advice is sound and realistic. the range is 85 to 115ftlbs from multiple manufacturers. 90lbs is a good number. some times too tight at the track, can cause problems getting them off and cause breakage. This is 20 years of racing and 1000s of wheel removals at the track.
Last edited by mark kibort; 04-18-2016 at 03:36 PM.
#34
Drifting
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
OEM porsche stuff is great, but pads don't last long. I use Pagid Yellow that last much longer. I believe switching back and worth may not be a great idea due to constant rebedding with different pad materials. Unless you only do a couple of events I'd leave track pads in.
#35
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
OEM porsche stuff is great, but pads don't last long. I use Pagid Yellow that last much longer. I believe switching back and worth may not be a great idea due to constant rebedding with different pad materials. Unless you only do a couple of events I'd leave track pads in.
#36
Drifting
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
as you start pushing the car further and further, you will find the stock pads a little substandard, with very little bite when they get very hot. thats where a dual purpose pad like a Pagid orange works very well. (its classified as race (R-4-4) but i found its fine on the street. bed it correctly and it will give a lot of service with no downsides over stock pads. Pagid yellow is not a bad pad. it's an endurance pad, so it doesn't have the typical racing pad bite, but still quite good.
#37
Three Wheelin'
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
OP sounds like the crack pipe bit him.
OP, for all of us that instruct and have to ride in your car and coach you, please, please please leave your car as close to stock as possible. No, it won't be as fast, but that's a good thing, because what's not being talked about here is the importance of learning the line and execution and you don't need big brakes for that.
OP, for all of us that instruct and have to ride in your car and coach you, please, please please leave your car as close to stock as possible. No, it won't be as fast, but that's a good thing, because what's not being talked about here is the importance of learning the line and execution and you don't need big brakes for that.
#38
Three Wheelin'
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
And... When you have a problem, you consult the pros.
http://www.stoptech.com/technical-su...nd-other-myths
http://www.stoptech.com/technical-su...nd-other-myths
#39
Rennlist Hoonigan
which cost no drachmas
Lifetime Rennlist
Member
Rennlist
Site Sponsor
which cost no drachmas
Lifetime Rennlist
Member
Rennlist
Site Sponsor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
90 to 95ftlbs is just fine. it's not bad advice.+/- 5% is perfectly acceptable. no one's wheel is going to go anywhere on the track or road with 90ft-lbs of torque on the nuts. over tightening can have its downsides too.
it's practical advice.
there are many companies that spec 80ft'lbs.
my advice, first off here, is that his warped rotors could be caused by the apes at the shop who use impact guns and then just make sure they are torqued to min spec. that can make one lug near 150ft-lbs and others at the min level of near 90 or 95. that causes rotor warping and thats a problem. my advice is sound and realistic. the range is 85 to 115ftlbs from multiple manufacturers. 90lbs is a good number. some times too tight at the track, can cause problems getting them off and cause breakage. This is 20 years of racing and 1000s of wheel removals at the track.
it's practical advice.
there are many companies that spec 80ft'lbs.
my advice, first off here, is that his warped rotors could be caused by the apes at the shop who use impact guns and then just make sure they are torqued to min spec. that can make one lug near 150ft-lbs and others at the min level of near 90 or 95. that causes rotor warping and thats a problem. my advice is sound and realistic. the range is 85 to 115ftlbs from multiple manufacturers. 90lbs is a good number. some times too tight at the track, can cause problems getting them off and cause breakage. This is 20 years of racing and 1000s of wheel removals at the track.
Please, please, please, NO ONE LISTEN TO KIBORT. HE WILL GET YOU HURT.
#40
Race Car
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
From what I understand, Porsche is required by TUV rules to use 10.9 material on wheels studs. I also know that Porsche used lug nuts made of lower grade material so the lug nuts would be damaged well before the studs.
I won't comment on the Factory aluminum and steel lug nuts used on the air-cooled 911's, but have always torqued the steel nuts I use to 100 ft-lbs and have never and a problem with the lug nuts coming loose or being damaged. Of course, the steel lug nuts I use are supposed to be better than 8.8 which has a max torque value of ~102 ft-lbs.
The numbers above all assume dry threads.
There is no good reason in the world to use less torque than what is specified. I have no idea what taking the lug nuts on and off often has to with torque values used. It's not like the nuts are being used beyond their elastic limit. They can be used over and over again at the specified torque.
Torquing lug nuts under spec is not a good idea at all as far as I am concerned. Using less torque means you have less clamping pressure that the Factory specifies which means there is a better chance of the lug nut loosening. That is never a good thing.....
#41
Race Car
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
And... When you have a problem, you consult the pros. http://www.stoptech.com/technical-su...nd-other-myths
The rotors did look like they were stamped with ink. So it could be temperature ratings on the pads or lack of bedding (they were bedded per instructions but not bedded beyond that. )
This will either clear up some discussions I've seen or bedding techniques, or re-ignite, not sure which.
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
#42
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Never found that. Bite of OEM is great on my car, but it has decent size brakes from turbo. I just used up 50% in a weekend. Pagid yellows have been on for 11 days with 30-40% left. From what I read yellow is a better version of orange. Nobody uses orange on my car, either yellow or black or a combo. Blacks are harder on rotors.
You understand that every car is different, right? Just because some Toyota has 3 lug bolts and they are only torqued to 80 pounds doesn't mean that is correct for a Porsche. Porsche specified an exact value for a reason. My Suburban is 140 ft/lbs. Should I use that on the Porsche because some companies us it?
Please, please, please, NO ONE LISTEN TO KIBORT. HE WILL GET YOU HURT.
Please, please, please, NO ONE LISTEN TO KIBORT. HE WILL GET YOU HURT.
so, listening to me and tighting your lugs at 90ft-lbs is going to get you "hurt". really? ok Chicken Little.
My air-cooled 911 uses 10.9 M14x1.5 wheel studs. That is the Porsche Factory part. The maximum torque for a 10.9 M14x1.5 fastener is in the 130-140 ft-lbs range depending on the chart you look at.
From what I understand, Porsche is required by TUV rules to use 10.9 material on wheels studs. I also know that Porsche used lug nuts made of lower grade material so the lug nuts would be damaged well before the studs.
I won't comment on the Factory aluminum and steel lug nuts used on the air-cooled 911's, but have always torqued the steel nuts I use to 100 ft-lbs and have never and a problem with the lug nuts coming loose or being damaged. Of course, the steel lug nuts I use are supposed to be better than 8.8 which has a max torque value of ~102 ft-lbs.
The numbers above all assume dry threads.
There is no good reason in the world to use less torque than what is specified. I have no idea what taking the lug nuts on and off often has to with torque values used. It's not like the nuts are being used beyond their elastic limit. They can be used over and over again at the specified torque.
Torquing lug nuts under spec is not a good idea at all as far as I am concerned. Using less torque means you have less clamping pressure that the Factory specifies which means there is a better chance of the lug nut loosening. That is never a good thing.....
From what I understand, Porsche is required by TUV rules to use 10.9 material on wheels studs. I also know that Porsche used lug nuts made of lower grade material so the lug nuts would be damaged well before the studs.
I won't comment on the Factory aluminum and steel lug nuts used on the air-cooled 911's, but have always torqued the steel nuts I use to 100 ft-lbs and have never and a problem with the lug nuts coming loose or being damaged. Of course, the steel lug nuts I use are supposed to be better than 8.8 which has a max torque value of ~102 ft-lbs.
The numbers above all assume dry threads.
There is no good reason in the world to use less torque than what is specified. I have no idea what taking the lug nuts on and off often has to with torque values used. It's not like the nuts are being used beyond their elastic limit. They can be used over and over again at the specified torque.
Torquing lug nuts under spec is not a good idea at all as far as I am concerned. Using less torque means you have less clamping pressure that the Factory specifies which means there is a better chance of the lug nut loosening. That is never a good thing.....
the ONLY reason i go slightly less on torquing , is my own thoughts on the wear patterns of the studs or nuts AND one major factor of the spec,...... so they dont come off over time.. because we change tires every session, in 20mins, 90ftlbs vs 95ftlbs is not going to change the world or endanger your life , (MATT). Its just easier , strength-wise doing it all by hand. im calibrated to +/- 5 ft-lbs by hand at the track.
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
![bigbye](https://rennlist.com/forums/graemlins/xyxwave.gif)
#43
Drifting
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
to throw a wrinkle...porsche uses alum lug nuts on some cars while most of us use steel ones for the track. Does that change torques spec? Idk
Also, not mentioned, make sure the lug nuts are tightened while wheel is in the air and do it in a star pattern. Don't tighten one lug all the way but distribute the torque.
Start threading by hand so you dont crossthread them.
Be careful using impact guns for reasons above. And let wheels cool off a bit before taking them off right away.
Also, not mentioned, make sure the lug nuts are tightened while wheel is in the air and do it in a star pattern. Don't tighten one lug all the way but distribute the torque.
Start threading by hand so you dont crossthread them.
Be careful using impact guns for reasons above. And let wheels cool off a bit before taking them off right away.
#45
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I'm sure the car really benefits from nice round lug nut torque numbers
.
-Mike
![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
- 9 year old tires - check
- Cracked rotors - check
- Undertorqued lug nuts - well maybe, don't know because no torque wrench
-Mike