I am starting to track the car more and more. I am getting into all sorts of troubles, but don't have much clue and don't have a mechanic other than my nissan dealer $$$$$
So any advice is greatly appreciated!

Basically I have 2 questions:
1)
Is it normal on the 350z that the rear pads wear much faster than the fronts (non-Brembo)?
I researched this and found that to be the case for VDC on. But I always turned it off (I even installed the center console switch to disable the yaw sensor).
So after 3 track days (yaw sensor no power) on new slotted rotors with new nismo brake pads and only 2000 miles of street driving I am now down to the wear indicator in the rear but the front seem still fine (~40-50%?).
Aren't the fronts supposed to wear faster? Is it because the rears are so small that they get grinded even faster by the slotted rotors? Anything I can do about it? Or just keep buying rear pads more often than fronts?

I still have some OEM pads left, is it safe for street use to use OEM in the rear and NISMO pads in the front? Or will I upset brake bias?

2)
My track experience on the 3rd track day was really not as much fun, because the pedal felt so soft and it didn't seem possible to quickly brake hard. Instead it felt like you have to start braking early and push the foot down long and hard into this soft sponge... It didn't feel very reliable and I did not feel comfortable going "deep" into the corner (although my instructor told me to go deeper and that I am overbraking, but he didn't feel the pedal).
I felt like that from the start of every session, not just after several laps.
Should I start looking into investing into some used Brembos or BBK?
Is the increased size of e.g. a Stoptech BBK worth it compared to the Brembos in the long run?

I do have to admit though that only 1 flush with motul 600 brake fluid was done when the stage2 kit was installed and also I was too cheap and skipped out on the SS lines. Basically for these 3 track days the brakes were never bled. I just refilled brake fluid in the reservoir because the level reduced from Max to close to Min.


I think I will need to learn somewhere how to change brake pads and bleed them myself otherwise this hobby is not very affordable.
So far I am still the guy without any tools at the track, but I can see how this will have to change.

Thanks for any advice and feedback, and apologies for my newb questions.

(BTW Thanks again for the answers in my other thread about pad wear on track. I posted different percentages there, because I don't know how to read that accurately myself and the 3 people I asked all told me different estimates. Turned out I was still good for one more track day, although I followed Kolia's advice and inspected the pads after every session and then had to skip the last one.)

 

You're correct is saying that you should learn (and have the tools as well) to bleed brakes yourself. Being at the track and having a soft pedal usually means some air is trapped in the lines. It may take a few times to completely bleed the brakes. As for your question on the rear brake wear, if you do any searching here, you'll find this is pretty common with OEM brakes. The OEM rear pads seem to take much more wear than the fronts. Keep in mind that brakes seem to be THE limiting factor in how much fun you can have on a track day. If you really find yourself enjoying it, get ready to invest in a BBK (big brake kit). IMHO the best bang for the buck is a used Brembo setup (both F & R) off the classifieds section here. Good luck!

David Muramoto
Senior Editor
Nissan Sport Magazine

 

It does seem the non-Brembo brake will wear the rear faster than the fronts. The ABLS might still be ON event with the yaw sensor disconnected. You might want to take the rear backing plates out.

Slotted rotors will wear the pads faster.

There is no problem with running “regular” pads in the rear and “sport” ones on the front. You will have a bit less breaking power than with a sport/sport setup, but on the other hand, the car will be more stable under braking.

2)
You boiled your brake fluid. It now needs to be bleed to get fresh fluid in the caliper. You might need to do that every track day. Your instructor is probably right in saying you’re over braking. The irony is, you’re probably not braking as hard as the car can and you end up dragging the brake too long.

A BBK kit is certainly a good idea at this stage. The non-Brembo has a really hard time with the track.

 

I believe bleeding the brakes before every track day is a must!

Funny thing about braking at the track - it is the oppoisite of what you do on the street. You want to brake as hard as you can so the time you are on the brakes is the shortest. This way it gives the brakes more time on track to cool.

The best example is a track with only one braking zone. For this example our driver takes 60 seconds to do a lap, so if he brakes for 15 seconds - he has 45 seconds of cool down for the brakes. Now if he brakes harder and gets it down to 10 seconds than he has 50 seconds of cool down time. More cool down time means less likely to boil the brake fluid.

 

Thanks !

 

I have a 2005 G35 coupe that I've tracked, and I've had similar issues. My first track day, I got greedy and stayed on the track 1 lap too many. On my last lap going in hot into a hard right hander, my brakes failed. The pedal was starting to feel a little soft earlier, but as a retard, I decieded to push it. As I entered the braking area the pedal went to the floor at the Sunset turn at Buttonwillow. Luckily the runoff is really great, and I just went straight off into the dirt. I didn't even bother to turn. Anyway, after I roll into the pits, I check out my brakes, and the rear pad is crumbling away, and my rear rotors are heavily scored. Scanning the rotor with an IR pyrometer went off the chart as the rotor was well over 1000 deg F. Surprisingly the front pad and rotor held up, which seems to show that the brake biasing is somewhat heavy in the rear in my car which I'm assuming is similar in yours. I drove my car around for a month or so like this with the pedal feeling quite mushy as the fluid was boiled and absorbed a ton of moisture, and it was not very reassuring. After that I upgraded to a 13" stoptech kit all around. I thought about going with a used set of Brembos which were running about $2k or so when I looked around briefly, while my stoptech setup was $3400. Bang for the buck, the brembos are probably better. The advantages I saw with Stoptech was fact that it was new, so I didn't have to worry about the unit holding up. I was a little wary of the condition of a used setup and I don't want to find out the hard way if the brakes are bad. I think the stoptechs have a little better pad selection as well.

If you're gonna track your car a bunch, I reccomend going with 13" rotors rathe than 14"s just so you can stuff 17" rims on your car and get cheaper track quality tires. You'll pay a good amount more money for 18" track rubber.

Oh and lastly if you do change your brakes and want to bleed them yourself, I highly reccomend Speed Bleeders. They're a 1-way valve you install in place of your bleed screw so you can bleed your brakes on your own. You just pump the pedal until the fluid comes out clear. This saves time and effort. Also, since my stoptechs have 2 bleed valves per caliper (8 total), this saves me a bunch of time. Speed bleeders with a bleed bag = 0 mess and less time.

Hope this helps.

 

Thanks that definitely helps...

I thought the stoptech kit goes for >4k?

My nissan dealer didn't make problems installing the stage 2 upgrade, but not sure if they would also install aftermarket calipers...

So I am looking for used brembos...

Is it true that a 13" stoptech kit is better for tracking than the OEM brembos??
I have heard that somewhere, but maybe they meant the 14" kit, as the 13" seems very similar in size to the OEM brembos and shouldn't be much different on the track?

 

My experience with the Z sounds pretty similar. I went through the rear pads in only 2 road course track days. My instructor was giving me similar advice to brake deeper into each corner. I remember telling him the 2nd day that I thought I was feeling brake fade and he said no it couldn't be. Right before the last run I refueled and this is when I noticed I have gone through 100% of the rear pads. Steel to steel! I didn't make the last track session due to the issue. The front pads looked fine and had 80% plus pad life. In fact, I put HAWK pads on the rear and ran the next time with the same front pads and I had no problems. I checked the rear HAWK pads and they showed almost no wear for 2 days of track time on the same course. The front pads were down to less than 50%. I never use VDC and I. I rarely felt fade with this OEM set-up. I could tell when I had poor braking technique that is when I would feel some occasional and minor fade. The more I improved my braking technique the less often I would feel fade. I'm convinced the stock brakes are pretty good IF you learn how to brake correctly and use the right pads. (non-brembo) If your pedal is feeling soft that is NOT GOOD and is a major safety issue.

Now, I ultimately upgraded to a Stoptech 4 wheel BBK. Mine is the larger rotor size. (14.1" ) Man, I love these brakes! With track pads in the front and rear its amazing how good the Z brakes! I've not had any pad wear or fade issues over several roadcourse track events. The other thing I'd keep in mind is the advertised costs of these BBK's is A LOT different than what folks will sell them at. Send the emails out and get the pricing. If I had known the pricing was going to be as different as it ended up I would have bought the kit several months earlier. Oh...by the way, changing pads on the BBK's is even easier than the stock pads. Basically sliding them out like a cassette and sliding them back in. The calipers don't need to move. It take more time to get the wheel on/off versus changing the pads.

Good luck.

 

I had similar experiences as you did. I held out with the stock non-brembo brakes for about 8 track days. I tried different pads, SS lines, motul 600, cutting the dust shields, etc. Looking back, I should have just done the upgrade and been done with it.

So you need to decide how serious you are and how many days a year you want to track the car. The better you get, the more you need good brakes. I have gone through the whole upgrade pattern. First just the front Stoptech 332mm. Second the rear 328mm. Then upgrade the fronts to 355mm. Finally get the new 6 piston fronts. The more serious you are about tracking the car, the more sense it makes to upgrade the brakes only once. True, 17" wheels are nice for price and R-compounds are one of the best upgrades you can make. But make sure that 13" brakes are adequate for you. Also factor in brake pads, the better you get the more aggressive and expensive the pad you will need. The 4 piston Stoptech caliper costs about $250 for decent pads. The 6 piston Stoptech caliper costs about $400 for decent pads. With all the kits, also look into brake ducts for the fronts. A cheap home built solution will get you by and help out.

Perhaps as a start, I would defintely cut the dust shields and get ducts as those are useful with any kit (including the stock brakes). Then figure out what tracks you are going to run the most. Are they brake intensive tracks or not? Then figure out how much you like tracking your car as it gets expensive quickly. Anything that you can do yourself maintenance wise is cost savings. I would recommend finding a friend with tools and experience to walk you through some of the basics (bleeding brakes, changing pads, etc.). Also +1 on calling on pricing of a BBK and seeing the real pricing.

 

Thanks a LOT for all this advice !

 

pedroosan, what track were you running on?

 

What's funny is that no one has mentioned getting more air to the front and rear brakes. That should be the first thing done, before spending money on a BBK. For $100 I think that a lot of the problems encounterred can be solved or reduced significantly.

 

More Air? Not sure what you are talking about.

 

I mentioned that in my post with removal of the dust shields and addition of front brake ducts. For the fronts, the problem is that there really is not a great kit, most are home-built. Also, most people don't like cutting the underbody plastic pieces to allow the tubing to go through. For the rears, it is very difficult to get better airflow.

Do you know of any good brake ducting systems?

I went through the process of evaluating body kits a while back as well as that might be a good approach. Never did pull the trigger on that purchase. The Stillen one has some kind of ducts and a couple of others had holes in the right spots.

 

100$ for brake ducting? Where?

 

Neoprene 2" ID air ducting - 12' for $50.00
Bumper mount air inlet plastic ducts (2) - $32.00
Exhaust tubing 2" OD - 1' $2.50
Hose clamps stainless (8) - $10.00
Pop rivets (36) - $2.00

A few hours work with sheet metal shears, holes saws, and a rivet gun and you've got ducted air to the front and rear brakes.

 

Ah - you are talking about cooling air - for some reason I was thinking about air in the brake fluid.

Yet, I think your prices are a little off - I just ordered the parts this past weekend for the front brakes.

2 - Air Duct Single Block (what you call Bumper mount), 2" Silicon Ducting (need this to handle the high temperatures near the brakes), 2 - 3" to 2" adapter (you need this for as all duct blocks have 3" hose connector).
The cheapest cost with tax and shipping was $124 and doesn't include any hose clamps or pop rivits.

 

I purchased the NTech kit and it has allowed me to mobe to the 300 foot marker to break from 110 to 45 MPH. I previously would have started at 400 ft marker and would get shudder. This is now gone and the peddle pressure seems to be less. The pedal pressure could be all in my head but the improvement in breaking distance is amazing and very measureable.

 

'Cheap' solution that works pretty good for non-Brembo cars:

1. ATE Super Blue brake fluid
2. Carbotech racing pads (Front: XP10, Rear: XP8)
3. Stainless steel brake lines
4. Home made or purchased brake ducts

Why this as a first step?
1. It works, but you will have to replace the pads after 4 to 6 track days.
2. The pads are consumable, if you don't like them, they will wear out. The other items are needed/helpful no matter what you do. Note: Those pads tdo make a LOT of noise when used on the street. I would strongly consider swapping them with other pads for the street.


If you are still not happy, I'd go one of two routes.
1. Upgrade the rotor size using one of the RacingBrake kits. The OEM caliper with the larger rotor will be a definite step up, and you can upgrqade from that to using the RacingBrake 4 piston caliper.
2. Upgrade to a set of used Brembos. There is a complete set for sail trianglez.com for $1,200, including rotors and a selection of pads.
3. Go get a set of StopTech and be done with it.

Good luck

 

PIR (portland international raceway):
As a novice I cannot really judge how brake intensive this course is compared to others. Per lap you have 1 high speed brake zone from ~110->60 (2nd gear chicane after long straight). And maybe 1-2 more corners that seem to be hard on brakes. Especially the one after the backstraight is weird: Although you can enter the turn fairly fast (4th gear) it seems to be slightly downhill, because somehow the braking there takes very long and feels very ineffective. You are just braking for a 5th->4th shift and yet in that turn the pedal feels scarily soft.



Thanks for all the very helpful posts!

Tracking is kind of addictive... you think you are done for the year/season and then there is always this other event that you could still join in a few weeks...
And it seems to be a lot about balance: first street tires, streetable pads, then you get into more serious brake setups, which will probably lead to having to get dedicated track tires sooner or later... From reading other posts it seems that either the tires are too good (r-comp) and then the pads wear too fast or the other way round...