A couple months ago I did the 300ZX brake upgrade to my 240SX. I installed 30mm Brembo cross-drilled and slotted rotors with iron calipers. I kept the stock master cylinder. I have been very satisfied with the braking performance.
Upon experiencing some steering wheel shimmy, I had my mechanic look at it and was told that both rotors are slightly warped.
I know this is possible, but is it probable, in such a short time? With the stock master cylinder? With cross-drilled rotors? With the iron calipers which I have heard many people say disspate heat much better then the aluminum ones? I thought my days of experiencing rotor warpage were in the past with these rotors.
Has anyone else experienced this problem? Is it odd or common?
Thanks.
Ever warp Xdrilled rotors?
Man, I am sorry, I completely forgot to include that. It's a very good question.
I am using Project Mu brake pads. They came highly recommended. But maybe that's the problem. Or is it possible that 300ZX calipers on a car nearly a 1,000 lbs lighter can possibly be too much brake force?
I wonder if any others have had this problem. Or is it perhaps the brake pads I am using?
I am using Project Mu brake pads. They came highly recommended. But maybe that's the problem. Or is it possible that 300ZX calipers on a car nearly a 1,000 lbs lighter can possibly be too much brake force?
I wonder if any others have had this problem. Or is it perhaps the brake pads I am using?
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Q45tech
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300zx warped the same rotors so realistically the heat sink [thermal rise] capacity is only the difference in weight between old oem and the new rotors.
Try Nissan oem 300zxtt pads.Where was the greatest warp, the inside surface?Did you index the rotors to measure the new runout [bad hubs bad bearings forcing a true rotor to quickly warp to conform]
Try Nissan oem 300zxtt pads.Where was the greatest warp, the inside surface?Did you index the rotors to measure the new runout [bad hubs bad bearings forcing a true rotor to quickly warp to conform]
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BuudWeizErr
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Gary@Tirerack
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BuudWeizErr
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Gary@Tirerack wrote:Yes, Drilled rotors that aren't oversized are more likely to warp than their slotted counterparts. Especially if they were not drilled *BY* brembo, but were just plain brembos that were drilled by an aftermarket driller.
Thanks Gary for your input. I am not sure what you meant by "drilled rotors that aren't oversized". The rotors we are talking about are Z32 size, cross-drilled, and slotted, and they came from Brembo that way.
Do you mean to say that cross-drilled rotors are more likely to warp than slotted-only rotors? Wouldn't that be a case against cross-drilled rotors? Isn't the primary function of cross-drilling to improve cooling? If so, wouldn't that feature reduce the chances of warpage?
I am no expert - just an average consumer - so would greatly appreciate your input, if and when you have some time available to respond.
Thanks.
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dreamsOfSkylines
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The cooling gain from the increased surface area that cross-drilling provides is more than negated by the loss of material, so actually they dissapate heat worse. My understanding is that cross-drilling was orinally developed to deal with a "gassing-out" phenomenon in early brake pads where the binding agent in the pads would boil and then release hot gases, which would create a thin layer of gass between the pad and rotor (this is bad). Supposedly modern brake pads don't do this if they are used within their operating temperature range.
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austins240
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with every set of slotted and cross drilled rotors i've ever purchased they have always had a "beak in period". did yours come with specific instructions for this?
they do this to allow propper heating and cooling and gradual rates (much like a new clutch or after an engine rebuild) and to get all of the tolerances evened out. if this is not done (especially on drilled rotors) the head disipation will be sever enough to acutally crack the rotors around the drill holes because of differences of cooling. they also usually require warming up of the rotors and pads on a course to avoid shattering and warping.
biggest thing i would reccomend is following break in instructions and if they are fully drilled rotors (not dimpled) that you allow a decent warm up of them before heavy breaking. a more solid pad will cause them to provide better grip at the cost of short rotor life and lengthy warm up time. vise versa for softer pads.
guess that's about it. have fun
laters
austin
they do this to allow propper heating and cooling and gradual rates (much like a new clutch or after an engine rebuild) and to get all of the tolerances evened out. if this is not done (especially on drilled rotors) the head disipation will be sever enough to acutally crack the rotors around the drill holes because of differences of cooling. they also usually require warming up of the rotors and pads on a course to avoid shattering and warping.
biggest thing i would reccomend is following break in instructions and if they are fully drilled rotors (not dimpled) that you allow a decent warm up of them before heavy breaking. a more solid pad will cause them to provide better grip at the cost of short rotor life and lengthy warm up time. vise versa for softer pads.
guess that's about it. have fun
laters
austin