Rotor vibration
#136
Rennlist Member
its funny... i had a pit crew member (for one of my races where i had help) forget to torque the bolts. 20 min qualifying session. All the lugs were still hand tight.. he felt horrible , but no harm done.
#137
Rennlist Member
Just turn it until it clicks. Also, don't torque them hot.
With experience one can judge how fast to turn the wrench. With large fasteners, like lug bolts, this doesn't matter much. On smaller stuff it pays to be patient and turn more slowly.
When I'm real paranoid about a bolt, I'll use a beam torque wrench, that way I can see the torque building up as the fastener tightens.
-Mike
With experience one can judge how fast to turn the wrench. With large fasteners, like lug bolts, this doesn't matter much. On smaller stuff it pays to be patient and turn more slowly.
When I'm real paranoid about a bolt, I'll use a beam torque wrench, that way I can see the torque building up as the fastener tightens.
-Mike
basically, if you go too fast, then you risk the chance of overtightening. you know, feel the click and then stop after you feel it. its worth 5ft/lbs more.. not a big deal unless you are tightening rod bolts or water pump bolts into an aluminum block.
#138
Rennlist Member
snip....
For me personally doing lug nuts at the track, I use my old fashion clicker, for steel nuts on good quality steel studs, with good wheels, 5 lbs TQ off won't make a difference either way.
When I ran a Honda dealership over torquing their cheap steel wheels was easy to do and would cause a vibration.
I've never had that problem with an OEM PORSCHE wheel.
For me personally doing lug nuts at the track, I use my old fashion clicker, for steel nuts on good quality steel studs, with good wheels, 5 lbs TQ off won't make a difference either way.
When I ran a Honda dealership over torquing their cheap steel wheels was easy to do and would cause a vibration.
I've never had that problem with an OEM PORSCHE wheel.
gosh, and look at all the flak ive taken for that!! Gents, its 5%... lay off!
you change wheels, tires, studs etc, that spec is a guideline. use your head... stay within 5% and the entire world can still be at peace.
folks should realize that uneven torque is the problem, and many shops and those that blow through the clicker on the torque wrench can over stress unevenly the wheel and rotor and cause issues. (vibration)
See my very first post with info and experience. THE OP probably had this issue, more than likely.
#139
Drifting
I spoke to a brake engineer at COTA a few years ago, he told me modern quality discs are pretty hard to warp. Most vibrating are uneven pad deposits. I took a rotor hone to my rotors on my GT-R and it fixed the problem.
#140
Rennlist Member
the pad "deposits" can and should be removed as soon as they are laid down. the smir'ring you see, is usually on new pads and the first session and street cars that don't get the brakes that hot. again, my experience is real, shared by many and i showed the pictures of PFC11s after one session and then after the race. there was no deposits seen felt, or removable after the race. again, its my experience and shared by others at the track that punish their brakes often.
other times its a concentric problem where the brake rotors are not centered.(using non stock parts) centering screws are usually not good enough. centering rings are. (or having the rotor have the locating pads in the casting)
#141
Racer
Join Date: Sep 2007
Location: Southwestern Ontario
Posts: 335
Likes: 0
Received 0 Likes
on
0 Posts
ive just seen the mistorquing of rotors to be very common cause to "rotor warping" not permanent, but it is real.
the pad "diposits" can and should be removed as soon as they are laid down. the smirring you see, is usually on new pads and the first session and street cars that dont get the brakes that hot. again, my experience is real, shared by many and i showed the pictures of PFC11s after one session and then after the race. there was no deposits seen felt, or removable after the race. again, its my experience and shared by others at the track that punish their brakes often.
other times its a concentrically problem where the brake rotors are not centered.(using non stock parts) centering screws are usually not good enough. centering rings are. (or having the rotor have the locating pads in the casting)
the pad "diposits" can and should be removed as soon as they are laid down. the smirring you see, is usually on new pads and the first session and street cars that dont get the brakes that hot. again, my experience is real, shared by many and i showed the pictures of PFC11s after one session and then after the race. there was no deposits seen felt, or removable after the race. again, its my experience and shared by others at the track that punish their brakes often.
other times its a concentrically problem where the brake rotors are not centered.(using non stock parts) centering screws are usually not good enough. centering rings are. (or having the rotor have the locating pads in the casting)
#142
#143
Rennlist Member
you missed the point (points) where i have been calibrated.
(others have verified that this is not hard to do)
seriously! im with in a couple of lbs max ... the problem is when the air rattle guns are used and then verified for min values. some are 95 and some are 140. all pass the clicker test.............but do you see the problem? this is my point and always has been here.
(others have verified that this is not hard to do)
seriously! im with in a couple of lbs max ... the problem is when the air rattle guns are used and then verified for min values. some are 95 and some are 140. all pass the clicker test.............but do you see the problem? this is my point and always has been here.
#144
Race Car
The pad transfer layer is always there, Mark. Just because you can't always see it with the naked eye does mean it is gone. A non-uniform transfer layer is usually what causes judder.
Also, read this:
http://www.stoptech.com/technical-su...nd-other-myths
Note the author's name: Carroll Smith
Also, read this:
http://www.stoptech.com/technical-su...nd-other-myths
Note the author's name: Carroll Smith
#147
Rennlist Member
The pad transfer layer is always there, Mark. Just because you can't always see it with the naked eye does mean it is gone. A non-uniform transfer layer is usually what causes judder.
Also, read this:
http://www.stoptech.com/technical-su...nd-other-myths
Note the author's name: Carroll Smith
Also, read this:
http://www.stoptech.com/technical-su...nd-other-myths
Note the author's name: Carroll Smith
you saw my discs.... you saw that NOTHING came up with green pad or even sand paper.... but is still there. you saw my discs after one session.. you saw my discs after the race. i have the post race discs... just tell me where should send the discs to what laboratory and we can see if the pad material is on the disc.... also , ill send with the exact pads that were on the rotor.
what level of 'layering" are we looking for? the "experts" are saying .00010".
if so, i should not only be able to measure that, i should be able to see to, right?
dont forget to say your bedding prayers at the church of Rotortology. dont forget to try and recruit, VR and DT. they need to be saved!
#148
Rennlist Member
I don't care at all about your stupid layer of pad material.
All I care about is that you stay on the west coast. I don't think you take being safe out there seriously and that puts everyone around you at risk. I don't ever want to be anywhere near you on a track.
In the event you're just trolling, well, good job.
All I care about is that you stay on the west coast. I don't think you take being safe out there seriously and that puts everyone around you at risk. I don't ever want to be anywhere near you on a track.
In the event you're just trolling, well, good job.
#149
Rennlist Member
I don't care at all about your stupid layer of pad material.
All I care about is that you stay on the west coast. I don't think you take being safe out there seriously and that puts everyone around you at risk. I don't ever want to be anywhere near you on a track.
In the event you're just trolling, well, good job.
All I care about is that you stay on the west coast. I don't think you take being safe out there seriously and that puts everyone around you at risk. I don't ever want to be anywhere near you on a track.
In the event you're just trolling, well, good job.
how old are you?.. you too are acting like a grade school.
think about it. what have i recommended to be safe? (or not be safe)
1, bed the pads.... winders said dont bed them, just run them
2, use the blip downshift if you lose brakes...... VR says, just coast of the track, out the gates and into city streets.
3. keep RPM in the upper 75% range always if you are qualified to race/TT
4. monitor your torque on the wheel lugs.. unevenness can cause warping or vibration
5. i mentioned , not advised that i can get my lugs with in 5% max below spec.
6. I mentioned that i use 2006 tires from WCGT, 2010 hoosiers that have been stored in climate controlled environment and are still quite safe for practice and street driving.. proved by the fact that they are only a 1 second off their original pace.
Now, how is any of the topics of the month that you and your pals seem to get your panties in a wad about, dangerous??
yet I constantly see people blaming tires, brakes and other drivers for their lack of proper race craft training. Actually, i could help you, but you and the others know more.. so have fun with that.
It is not me that is the danger, it is those with a closed mind and inability to learn.
in the 15 years of racing, and literally 1000s of laps, i made one poor call to safety.... running stock brake lines that were original to the car. they blew on one of the most dangerous places of any track to blow.... never again will i run stock brake lines. my technique of handling it, i tried to share with others.. even seeing another same event with another car owner , turn out poorly using the VR technique of not downshifting. i was able to save the car and not endanger anyone. i hope at least one person picks up on that and actually practices that technique. other than that.. there is no on you will ever meet at the track that takes safety more seriously than i do.. with my car and with my driving and i think my record proves that as well.
#150