I'm trying to decide if I should take the plunge and upgrade to a set of the Z1 2-piece rotors for the front and rear for my Akebono brakes. I currently have 1 piece drilled and slotted stoptech rotors all around which I believe are 30 pounds each for the fronts and 22 pounds each for the rears, totalling 104 pounds of rotor weight . According to Z1, the 2pc fronts are 20 pounds each and the rears are 15 pounds each, totalling 70 pounds.

My current rotors are in excellent condition and only have a few thousand miles on them (installed last summer) so I'm not necessarily in need of new ones, but I would be interested in the upgrade if the switch to 2pc all around would make a noticeable difference. The car is a weekend toy primarily, but it may see some autocross next month . Go for it? Wait it out until new rotors are needed?

Input appreciated.

 

Any amount of unsprung weight removal will help performance. Also, the corresponding loss of reciprocating weight from a lighter rotor swap will also increase performance. But I'd check those weights carefully; it's doubtful even a two piece rotor will be 50% lighter than your present one piece units. If your current rotors are in excellent shape, you might consider keeping them and possibly avoiding moving up a class due to what would be a brake upgrade.

 

Just from my personal experience - I did not notice much of a difference with 2-piece rotors as far as weight goes. I did notice a HUGE improvement with heat dissipation.

If I were you and I weren't boiling brake fluid or turning calipers from silver to gold (like I was doing), I would keep what you have. Unless you have unlimited budget. That opens a slew of different doors.

 

We did some measuring in regards to temperature at our last track day. I run the Akebono setup on my z with the 1 piece rotors and a friend runs ROTORA's with the 2 piece setup. I was seeing high 300's immediately after coming off the track while his never broke 270. We were both lapping Putnam Raceway in the 1:24 range.

 

I was the friend. Haha

 

I also have Z1 two piece rotors front and rear on a 370z with Akebonos. I have only done a comparison on the dragon at ZdayZ (2014) vs a 350z HR with Akebonos and stoptech front and rear slotted rotors with the heat gun. My rotors were consistently 20-25 degrees cooler. Both cars are very similar in weight and were running Carbotechs... and we were not going easy on the cars. The run we checked temps at the end of each leg was chasing the forged GTR and crew in the early morning and they were pushed about as far as you can take them on the street.

At the track these things are amazing. I have not been able to find a flaw in them except that if you are running a high quality pad that it can overpower the tires. Make sure you have good rubber to support them.

As far as performance from weight savings I could tell a difference in handling immediately. The car felt much more delicate / precise ... especially when coupled with a lightweight wheel like an RPF1.

If your current setup is still in good shape just upgrade and recoup some of the expense by selling your current setup. You will not regret it.

 

1st, the rotor really doesn't have much to do with stopping force. If you are overpowering the tires, you need less aggressive pads. The 2-piece rotors don't have anything to do with that.

2nd, I think the "better" handling is similar to the butt dyno. After someone installs an intake, they think their car is faster and can "feel" it. This is highly unlikely when they only gained 1whp. I am not saying having less unsprung weight doesn't do anything, but it isn't a night/day difference.

3rd, if you were only experiencing a 20-25* heat difference, you weren't pushing them very hard. As Everet said earlier, we were measuring temperatures straight off of a 30 minute fast-track session and we saw a difference of around 100* every time.

 

1. It had alot to do with the rotors. I would experience fade with the same pads prior to the upgrade. Once excessive heat issues were alleviated it exposed the compound of the tire on extended sessions was not up to the task. I feel this is useful info for anyone doing this upgrade

2. This will be subjective but noticeable to me. I noticed the same amount of steering feel / response change going from the 24lb front 28lb rear volks to 20/20 RPF1's with these rotors compared to one piece disks. YMMV.

3. I was very specific that I have not measured temps at the track. The dragon is not a racetrack and is nowhere near as demanding. That is the difference of a Mountain Road vs a designed facility without oncoming traffic or cliffs with long straights and tighter braking zones. Any comparison to temps from the dragon vs track were not implied and only postulated by you. At the end of the day there was a difference even on the street.. Which is good info for the OP if it is a dual use vehicle.

 

Not so sure I agree with you 100%. Owning multiple sets of wheels with varied weights, it's a noticeable difference when I swap a 31lb wheel to a 20lb wheel.

 

Appreciating the feedback guys. Great information.

This is part of why I want to lighten things up around the rotors. I have fairly light wheels (volk ce28n) which are around 20-21 pounds in my sizes and having rotors that weigh 1.5 times as much up front makes me feel like I'm anchoring down the light whees.

 

Just coming from my personal experience here, I think that is more of a placebo effect. It may "feel" better, but it is really psychological. I am not saying there is no gain (as I said before), I am just saying it isn't like your car handles like **** and then all of the sudden it is on rails.

 

1. Fade is caused by heat. You mentioned nothing about heat in your first post saying that the pad could overpower the tires. That wouldn't change rotor to rotor. Now, the amount of fade will absolutely change.

2. I am just saying I don't think you can actually feel this change. Simple as that. Not calling you a liar, I am just saying it is most likely psychological.

3. You yourself said that you pushed them as far as they could go on the street. You made it sound like you pushed them extremely hard and at the end of the day there was only a 20* difference. That may not be how you meant it, but remember, this is the internet and everybody takes context a little different.

I wasn't trying to offend you, but clearly that happened - so sorry if I offended. Definitely didn't mean to do so.

 

Not offended at all. I just wanted to make sure my experiences helped the op without writing a novel. Also probably should have mentioned this was in america but I was speaking in Celsius not Fahrenheit. My gun defaults to C and I just run with it LOL.

 

OP all this aside I have the Akebono upgrade and track my car. I love it. It performs well and does everything I need it to do.


Here is a video of me almost running into Carfreak in the white 06Z. An S2000 tried to cause a wreck. The brakes worked beautifully.

 

Love that video. Would also love a new rear bumper hahaha

Can't wait to go back.

Skip to 8:00 to see me pass that GT-R
15:59 "White Nissan is on pit row" Ooops...got black flagged

 

Damnn both of you guys have beastly cars. You were chasing everybody down

 

Rotors are a little bit different than wheels and tires. Yes there will be a difference in performance but because the weight of the rotor is already closer to the center point of the axle the weight difference is not felt the same as it is going from a heavy tire to a light tire because the weight is moved further out from the center.

 

Is your Z a 5AT car?

 

True true. Equal masses, smaller radius, smaller moment of inertia.

 

Thanks! We have a lot of fun. Both cars are completely stock (engine wise - not even intake).
Both cars are 6MT