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Leroy Peterson
27-10-2015, 08:16 PM
If you run upgraded or aftermarket calipers, share the details and your rotor size.

I currently run R32 GTR Sumitomo front calipers, one of the calipers has been causing issues on and off for a while (banjo bolt thread is stuffed, so got it helicoiled but its more of a temporary fix) and run N16 hubs with 280mm rotors.
Ideally I'd like to run 300mm rotors for ease, in the future it would be nice to put some racing 4 pots on the front and 2 pots on the rear.

1) How hard is it fitting AP racing/Alcon/Wilwood calipers to N16 hubs? custom spacer/brackets needed? is it possible to run them on N15 hubs?
2) Anyone run 2-piece rotors in 4x100?
3) Or is it worth ordering 280mm 4x100 rotors directly from DBA (custom order)?

J35U5
27-10-2015, 08:42 PM
Id be interested too leroy. Also what master cylinder and booster are people running. Im looking to upgrade the fronts(ad22vf's) and rears on my car.

sss4me
27-10-2015, 10:43 PM
i have heard that dba no longer do these rotors, could be wrong. sam flay (sam robert on poc/pga f/b) has done willwoods and ap racing and big disc's on his almera. has some spacers made to suit.contact him

999

Spectrix
28-10-2015, 02:16 AM
I currently run R32 GTR Sumitomo front calipers... and run N16 hubs with 280mm rotors.

Hi. Are you actually running a 280mm disc with R32 GTR calipers? That's way undersize :/




1) How hard is it fitting AP racing/Alcon/Wilwood calipers to N16 hubs? custom spacer/brackets needed? is it possible to run them on N15 hubs?

Yes you can run aftermarket calipers with N15 hubs, yes you'll need custom brackets. But you already have N16 hubs, no?




2)Anyone run 2-piece rotors in 4x100?

Two piece rotors are very uncommon in this market because $$$$




3) Or is it worth ordering 280mm 4x100 rotors directly from DBA (custom order)?

DBA will not custom make rotors, it's unlikely that they'll even supply blanks without a long lead time.
Running aftermarket cailpers with 280mm rotors will cost a lot of money and you'll gain nothing.

If you're set on replacing everything, the Skyline R34 GTT Sumitomo four pots will take a 30 x 310mm disc (machined down to 302mm to use with with N16 hubs, and redrill to 4x100 if that's what you're currently running).

Brake upgrades are expensive, a lot of work and substantial risk if you make a mistake. It pays to research carefully beforehand. If your R32 GTR Calipers aren't leaking then stay with them, they're very capable. But take note they're supposed to run with a 32 x 296mm disc. On N16 hubs it should be machined down to 288mm to suit those calipers.

Hope that helps. You should check out the brake upgrade thread here (http://pulsar.org.au/forums/showthread.php?164-Brake-Upgrade-N14-amp-N15).

Leroy Peterson
28-10-2015, 08:17 AM
Id be interested too leroy. Also what master cylinder and booster are people running. Im looking to upgrade the fronts(ad22vf's) and rears on my car.
I'm still running the SSS 15/16" master cylinder and booster, it seems to do the job fine.

Thanks for the info spectrix. Things that make me want to change calipers is:
A) if I just replace with another gtr caliper, all are second hand so need to get it rebuilt. Always have to buy in pairs.
B) I've had issues in the past with failed front bearings. The cost and time involved with sourcing N16 ABS hubs then machining them and redrilling is a PITA.
C) machining 300mm rotors to 280... Never again! I'm not sure who or how they mounted the calipers... But I would need spacers made up with the current calipers regardless.

In terms of cost... do it once etc...
I also know a number of people who have had good results with the aluminium calipers out of China (brands like D2, ATTKD etc)

I did ask Sam about his setup but he didn't really give any specifics (eg caliper part number).

Paullus
28-10-2015, 09:12 AM
This is a useful thread for finding Nissan OEM calipers and their respective disc sizes: Brake Upgrade N14 & N15 (http://pulsar.org.au/forums/showthread.php?164-Brake-Upgrade-N14-amp-N15)

Personally I went the 2 pot Maxima (A32) route a la Cozzmo: Twin Piston Brake Upgrade (http://pulsar.org.au/forums/showthread.php?162-Twin-Piston-Brake-upgrade)

My setup (not aimed at you Leroy, you're obviously chasing bigger!)
A32 Maxima 2 pot calipers
280x26mm DBA discs (not slotted, the T2? were about $230/ea from what I remember!; RDA do a slotted for cheaper if you *really* want slots)
QFM A1RM pads
Penrite Racing Fluid (the old SIN fluid)
HEL braided lines
N16 hubs
and I'm still rocking the N14 7/8" master cylinder. The pedal has plenty of travel which I've grown to like (especially that I don't have ABS) however sometimes I think I'm hitting the end of it when I've braked a bit deep/in too hot. I think it's got a minor leak which doesn't help the cause, but I'll probably upgrade to a 15/16" (N15 SSS) BMC soon (haven't forgotten Leroy!).

Have braked from 160-170 will no dramas multiple times (with a bit of cooling between each run), and they haven't even had a whimper after 4x1.2km race laps on moderately bendy sprint circuit.

The best part is there is no special wheel requirements to clear the 2 pots, except with N15 SSS stock wheels; they require a small spacer or the locating ring on the hub to be removed (most aftermarket wheels have a large bore to fit over).

http://users.on.net/~paullus/pga/introthread/10961751_10152573510332143_1196332790_n.jpg

Martin
28-10-2015, 09:38 AM
That's a pretty cool setup

I use the QFM A1RM pads, they work great (you'll never over heat them) and they are very affordable
(although mileage is shorter than ProjectMu but they are twice the price so works out similar in the long run)


I'm still rocking the N14 7/8" master cylinder. The pedal has plenty of travel which I've grown to like (especially that I don't have ABS) however sometimes I think I'm hitting the end of it when I've braked a bit deep/in too hot. I think it's got a minor leak which doesn't help the cause, but I'll probably upgrade to a 15/16" (N15 SSS) BMC soon (haven't forgotten Leroy!).

Having plenty of travel will give good feel and modulation - which is a good thing without ABS

Would be good to find and fix that leak...

jacsss
28-10-2015, 05:08 PM
Currently running the TDMi 5 Stud kit

Front; R33 GTST calipers with matched DBA4000 T3 rotors, machined to 288mm with Project Mu HC800 pads and custom braided lines

Rear; A32 maxima calipers, DBA4000 T3 Rotors to suit A32 Maxima with Bendix GCT pads

Currently on a pretty boring daily driven n15 SSS with ABS and standard booster/master cylinder

Project Mu's are awesome, if i was to ever track the car i would probably put them in the rear also.

Ruddigger
28-10-2015, 06:48 PM
Im running R32 GTR calipers , I cant remember the exact diameter of the front discs but they aren't must off a standard GTR disc

https://scontent-lax3-1.xx.fbcdn.net/hphotos-xfp1/v/t1.0-9/1929082_66984471018_599880_n.jpg?oh=77ab2230807c69 d26de18307f8b061da&oe=56C6D195

https://scontent-lax3-1.xx.fbcdn.net/hphotos-xap1/v/t1.0-9/10391704_186049411018_3875592_n.jpg?oh=8bf094da3ec 8eb213af88fdbce92ebe5&oe=56C4F2E2

N16 Hubs with standard pads

I also remade some brake lines and im now running 1" or 15/16 something like that master cylinder , i have bugger all brake pedal movement but works well

https://scontent-lax3-1.xx.fbcdn.net/hphotos-xfp1/v/t1.0-9/1929082_66984441018_5581590_n.jpg?oh=2c9e8d97ea8ee 8767aacf07762906023&oe=56C83710

Spectrix
28-10-2015, 11:05 PM
My brake setup is in about the largest I could put together staying with bolt on items on an N15 SSS.

N16 Front & Rear hubs (4x114.4mm stud pattern)
Skyline 4 Pot sumitomo (R34 GTT), 310 x 30mm slotted rotors - machined down to 302mm, redrilled to 4x114.3
Rear - Maxima A32 calipers with 278 x 9mm slotted rotors, redrilled to 4x114.3
Master cylinder - Standard N15 SSS ABS 15/16"; brake pedal modulation is good with this setup.

Boosted VLAD
29-10-2015, 05:09 PM
Spectrix,

I have an N14 with:
N16 front hubs
310mm R34GTT brakes machined down to 302mm
Gti-r rear brakes
Gti-r master cylinder

I was looking at re drilling maxima 278mm rotors to 4 stud and fitting them to the back, as you can use the a32 maxima calliper carrier brackets with gti-r callipers (that way your handbrake still works on n14) and the piston size and pads are the same so it's basically the exact same as using maxima callipers, the only thing you have to do is space the hubs out 12mm for the deeper rotors

But the main thing I'm trying it get at is that this setup is very unbalanced and I don't think that extra tiny bit of leverage and surface area of upgrading the rears is going to solve my issue,

I have Nissan rotors and TRW 700degree pads and nulon super dot 4 and I cook my front brakes halfway up the mountain, the rotors literally turn blue after hard driving and pushing in the pedal feels like stepping on a brick,
So I'm about to go down the road of fitting skyline twin pot rears and a brake bias valve,

So just a word to anyone doing 4 pots up front, just upgrading the fronts is worse then Gti-r brakes all around

Hopefully someone learns from my mistake ��

Martin
29-10-2015, 06:03 PM
I have Nissan rotors and TRW 700degree pads and nulon super dot 4 and I cook my front brakes halfway up the mountain, the rotors literally turn blue after hard driving and pushing in the pedal feels like stepping on a brick,

I find it exceptionally hard to believe you cook your rotors driving up a hill
Going hard downhill in a FWD, pretty easy to cook the brakes in that scenario

In the Pulsar Challenge series (track racing) we use N15 calipers and 257mm slotted rotors
Myself, I'm using QFM A1RM pads which are rated to 780 degrees
We can do a two hour endurance race, three big stops during every 1:13 lap, without experiencing any brake fade at all
(Granted some people with other pads ran out of pad material)

So the question is, why would your far superior braking system overheat and fade?


So I'm about to go down the road of fitting skyline twin pot rears and a brake bias valve

That ain't going to help in the slightest

The rotors turning blue certainly indicates you've encountered significant heat
You have great calipers and pads, but production Nissan rotors
The pedal going hard indicates your brakes got so hot that you encountered gas between the pads and rotor
My guess is you need rotors to match the rest of the brake system
More importantly, slotted rotors to allow the hot gases to disperse

Boosted VLAD
29-10-2015, 06:11 PM
Martin, I hear you,

My car makes 432whp and I drive the car very hard and this isn't a small mountain I'm talking about and has straight where I can do very high speeds
The same happens to me in the back straight of QR doing 240kph and absolutely slamming the brakes last second, if I do that a few times they turn blue and purple

And you hit the nail on the head when you said the pads/rotors get gas built up between them because they get too hot, that's exactly what happens,
This is why I will be upgrading to slotted and dimpled rotors next and trying different pads too

The problem is that even before they cook, the setup is too unbalanced,
I've come around turns and have not seen what's around them and had to put my foot on the brakes (not even that hard) and the car is so front bias with brakes it wants to spin the car out and I've nearly had the back overtake the front a few times,
Hence why I want to upgrade the rears too and get a proportioning valve to balance the setup

Boosted VLAD
29-10-2015, 06:15 PM
Martin, My aim is to get a balanced setup that is not going to fade

Martin
29-10-2015, 06:32 PM
My car makes 432whp and I drive the car very hard and this isn't a small mountain I'm talking about and has straight where I can do very high speeds
The same happens to me in the back straight of QR doing 240kph and absolutely slamming the brakes last second, if I do that a few times they turn blue and purple

Crap, I was not expecting that! You're packing some serious performance - LOL



And you hit the nail on the head when you said the pads/rotors get gas built up between them because they get too hot, that's exactly what happens,
This is why I will be upgrading to slotted and dimpled rotors next and trying different pads too

Perfect!



The problem is that even before they cook, the setup is too unbalanced,
I've come around turns and have not seen what's around them and had to put my foot on the brakes (not even that hard) and the car is so front bias with brakes it wants to spin the car out and I've nearly had the back overtake the front a few times,
Hence why I want to upgrade the rears too and get a proportioning valve to balance the setup

That's not a braking problem, that's FWD lift off over steer
Given the power and speeds you can do I'm not surprised you're encountering that

Did you put a stiffer sway bar on the rear???
Take it off, go softer in the rear, you'll be surprised with the result
(Even so, you'll have to watch out for this problem, straighten the steering wheel before braking)

Boosted VLAD
29-10-2015, 06:44 PM
Cheers Martin, haha I'm glad we're on the same page now I thought you weren't going to believe me

It's a stock SSS sway bar at the back, however I do have very hard suspension,

When I had Gti-r brakes all around I could press the brakes on a bend and it wouldn't do what it's doing now so it's definitely braking waaaaaaay too hard from the front ever since the upgrade so I definitely think I've messed up the balance, so I really hope my solution works but I will be sure to let everyone know

Martin
29-10-2015, 07:00 PM
Hmmm, if it is a braking problem I doubt that more rear braking will solve this problem because of the weight distribution and FWD braking bias
Less front braking would reduce the effect but you need awesome braking

How hard is your suspension? Front & rear spring rates?

Is the car very low, that will screw up the handling, need a lower ball joint on the front LCA's

Boosted VLAD
29-10-2015, 07:25 PM
The car is a little lower then I'd like it, I will be raising it soon because I want to get my control arms/ steering rack arms and everything else back closer to how it comes stock,
Spring rates are 11kg front 10kg rear,
(I'll be changing to BC gold 8/6s soon)

Martin,
I understand why you are asking all this because it is very important to every aspect of the cars handling,
Not many people realise the importance of this stuff and just the fact that your asking leads me to believe you know a thing or 2 about handling

However, I had Gti-r brakes with the EXACT same setup and they were much better balanced,
Then the only thing I changed was put big brakes on the front and then I could no longer brake any substantial amount on a bend unless I wanted to end up facing backwards, also braking very hard at the end of the straight at QR it boils the fluid in the front and turning the front rotors blue, that alone is telling me they are HOT AS HELL

The Gti-r brakes with the same fluid, just simple HPX pads actually faded no later or earlier so at this point I strongly believe that the issue is excessive front braking force, it feels like the rears are doing almost nothing


Realistically I have 2 options here:
1. Go back to Gti-r brakes, buy DBA 4000 series rotors for the front and rear, better pads and better fluid (what I should have probably done the in the first place)

OR

2. Upgrade the rears to twin pots, get a proportioning valve and better pads, rotors and fluid

Martin
29-10-2015, 09:49 PM
Whoa - them spring rates are very hard indeed - the 8/6 combo is right in the ball park

Yeah man, you know your car and it's history, I'm just chewing the fat at the pub and throwing ideas out there

Definitely need to solve the brake heat issue
I would have hoped that just T3's would be good enough (4000's cost more and very limited selection)
T2's may be fine in the rear - save a few $

The balance problem seems to be a riddle and I can understand why it's important to you to solve it - when FWD cars rotate on their own they bite hard
And it's often tricky trying to solve two problems that are interconnected - that's why I would solve the heat problem first, being the easier of the two to solve

Here's a very "left field" theory:
If the fronts have faded, reduced braking, maybe the rears are doing too much braking and turning you around?

Boosted VLAD
30-10-2015, 06:49 AM
Here's a very "left field" theory:
If the fronts have faded, reduced braking, maybe the rears are doing too much braking and turning you around?


Its a good theory, but It does it just as much on cold brakes, when you drive the car it feels like there is next to no rear braking and a massive amount of braking force at the front

Martin
30-10-2015, 09:19 AM
I will be very interested to hear what the solution is when you get it fixed

Cozzm0
06-11-2015, 03:32 PM
I went with A32 rears because the park brake on the N15 SSS Sucks balls and the A32 has a longer lever to get more leverage so it works better with the same effort.

Ruddigger
06-11-2015, 06:00 PM
I went with A32 rears because the park brake on the N15 SSS Sucks balls and the A32 has a longer lever to get more leverage so it works better with the same effort.


Yer yer that what i was going to say :rolleyes:

cav21
10-11-2015, 04:24 PM
If you where going to go the two pots how would you solve the hand brake issue?

Cozzm0
10-11-2015, 04:36 PM
If you where going to go the two pots how would you solve the hand brake issue?

Drum handbrake retrofit.

Spectrix
10-11-2015, 07:09 PM
I went with A32 rears because the park brake on the N15 SSS Sucks balls and the A32 has a longer lever to get more leverage so it works better with the same effort.

I used the A32 rear caliper bracket & handbrake arm along with redrilled A32 278mm rotors. I didn't swap the caliper body itself as it's identical and my originals are in good condition.
The handbrake is better, but I'd still call it mediocre compared to most drum/disc combos like the 2 pots. I've learnt to just compress the foot brake hard as I'm pulling the handbrake on.




Spectrix,

I have an N14 with:
N16 front hubs
310mm R34GTT brakes machined down to 302mm
Gti-r rear brakes
Gti-r master cylinder

...the main thing I'm trying it get at is that this setup is very unbalanced...



Hey Vlad, something worth checking on your setup is that those rear brakes are functioning properly.
Pistons in good condition,
Rubber seal intact
Rear lines properly bled
Slider pins well greased and not binding, etc.

I would check that before spending a lot of money changing components.

Boosted VLAD
15-11-2015, 01:35 PM
Everything is spot on Spectrix

We ran the numbers through a brake force calculator and what we found was shocking,
Stock brake force distribution is around 60% front, 40% rear

With the multiple pistons on the front and larger diameter the brake bias is 80/20 !!!!! Yes 80% front, 20% rear

In my opinion anything over a 5% shift reduces braking efficiency significantly, this is a lot more than that

Now you combine that with a car that has next to no suspension travel and is stiff as a rock and no wonder it has issues,

I'll be upgrading the rears soon, a friend of mine with a race car just had the exact same issue and he was only using 288mm fronts and he fixed his by upgrading the back brakes to skyline twin pots

Bengineering
03-12-2015, 03:21 PM
Not sure what's been covered or not as I was reading on my phone and probably missed stuff, but here goes:

1) Vlad definitely fades up the mountain; first time it happened he was running with me. Rotors turned blue and I told him they'd been overheated.

2) stock brake bias for an N15 setup is ~61/39. Rough calculations on Vlad's setup puts it at over 80/20, probably closer to 85/15. When he brakes he's experiencing rear end lift which is eliminating traction and forcing the bias even more toward the front than it is statically. This is why the rear gets so happy under braking, especially in corners.

Normally I would agree with lift-off oversteer as his main problem in corners, and it likely contributes somewhat; however, he experiences the same thing to a lesser extent even braking in a straight line. This is because of the rear end lift under braking due to the massive imbalance in brake bias.

3) gas between pad and rotor is fade, and the pedal should go soft during fade, not hard (in my experience).

4) it's not just Vlad's opinion that any shift in bias greater than 5% is detrimental to braking performance. That's shared by most sources I've come across in regards to this topic. Normally I'd provide references but I don't have the luxury to do so at the moment.

I'm sure there was more I wanted to add but I forgot.

Fun!

SSS_Hoon
03-12-2015, 03:41 PM
Spectrix, so u used the stock n14 rear calipers with a32 rotors?

Hrmm interesting.

Cozzm0
03-12-2015, 05:36 PM
Spectrix, so u used the stock n14 rear calipers with a32 rotors?

Hrmm interesting.

Spectrix has an N15.

SSS_Hoon
03-12-2015, 05:55 PM
^ ok nevermind

Boosted VLAD
03-12-2015, 06:22 PM
SSS_Hoon,
On the rear brake upgrade thread I've explained how you can do the maxima rear brake upgrade on an N14