Ok i'm a dork and actually went out and weighed factory rotors today at work. I've seen a lot of talk about how much different ones weigh so I figured maybe I could help clear things up. I weighed a 5th gen 00-01, a 5.5 gen 02-03, and the 6th gen 04-up. I used the digital scale on the AC machine.

5th gen- 40206-2Y505- 14lbs .15oz
5.5 gen- 40206-9Y000- 15lbs .9oz
6th gen- 40206-ZA500- 22lbs .5oz

These were all weighed in the cardboard boxes. BTW I have the 6th gen setup and don't notice the added weight, but i'm not racing my car or anything like that so idk. But it does stop good. Hope this helps.

 

can you do the diameter as well.

 

I just did the 6th gen upgrade and I can definitivly say that there is a difference in accelleration. I can feel the power, but it feels pent up. I would have to say that the mod added a -10 whp, but the stopping power is definitly better and in the autocross world, it's worth it.

 

I've never had a problem stopping my car nor did I ever have warped rotor problems. So to me the extra weight is a no no, but then again I don't race or autocross my car so I see no benefits in doing this mod.....but that's my
.02

 

omg, that's as much as my 19" rim...

 

Nobody has said it. I'm assuming this is the front rotors, right? Just clarifying things....

 

no man, the rotors from an rx-7 engine...j/k

 

Yes these were fronts, my fault for not stating it. I will pull them back out today and measure the diameter. I did the swap mostly because my fronts were toast when I bought the car, and I was going to have to buy rotors anyways. So I grabbed a pair of 6th gen rotors we changed under warranty, machined them flat and just bought the calipers and pads. So it worked out to cost about the same as just getting new rotors and good pads for the stock stuff.