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KNS Z32 Brake Conversion


TeriyakiBBS

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KNS Brakes has just release their new front brake brackets that will allow Subaru owners to run the Z32 4 pots. This kit will allow you to have more clamping power and is a lot cheaper then going either Brembos or a full BBK. You can use the standard legacy GT Rotors that are 30mm wide and all you will have to source are 30mm Aluminium or Iron front calipers off of a 90+ Nissan 300ZX. I recently got a set of Aluminium Calipers for $100 that have already been rebuilt and I will be getting the brackets ($150) soon. If you are doing a full upgrade it will cost under $500 for everything which includes Calipers, Dogbone Brackets, Rotors, Pads, and lines (if needed). I am also trying to source a set of Subaru FHI 2 pots for the rear. The Nissan calipers use a 2006+ WRX brake pad as well so it will not be hard to purchase or find.

 

For more info please look on this page

 

http://forums.nasioc.com/forums/showthread.php?t=2489687

 

When I have everything I will do a DIY and write up. It is not confirmed that the legacy brake lines will work (KNS is unsure) but I will figure that out when I get the calipers in the mail.

 

Stay Tuned

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^ This. The LGT rotor is clearly bigger than the WRX rotor that these brakes (or their cousins) would go on. I can see why you'd want to run these brakes on a WRX, but it seems like a downgrade compared with a stock LGT setup.

 

Actually since the rotor is a LGT rotor, the benefits of the LGT rotor and pad position stay intact. The advantage of the 4-pot caliper is that it gives a better pedal feel due to the clamping force being on both sides of the rotor and less flex. The other advantage is that if you are racing or tracking your car, it is significantly easier to change the pads out while hot on a 4-pot caliper than a swing arm style 2-pot. Lastly the pad choices and price of pads for the 4-pots are a bit wider variety and less expensive than the LGT pads.

 

-Mike Paisan

 

http://www.pbase.com/paisan/image/91072632.jpg http://www.pbase.com/paisan/image/145749898/original.jpg http://www.pbase.com/paisan/image/133406601.jpg http://www.whiteline.com.au/images/logos/perf1.jpg

11+ Years Maintaining, Modifying and Educating TriState Subaru Enthusiasts.

Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs

"Race Tested, Enthusiast Approved!"

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Actually since the rotor is a LGT rotor, the benefits of the LGT rotor and pad position stay intact.

 

Not talking about the rotor, more the size of the caliper (on a bigger-than-intended LGT rotor).

 

Does the stock LGT caliper/pad extend farther down "into" the rotor than the Z brakes shown above? It looks like less swept area to me.

LW's spec. B / YT / IG
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Not talking about the rotor, more the size of the caliper (on a bigger-than-intended LGT rotor).

 

Does the stock LGT caliper/pad extend farther down "into" the rotor than the Z brakes shown above? It looks like less swept area to me.

 

The entire pad will sweep the rotor, so it's only a matter of comparing the swept area of a LGT pad to the swept area of the FHI 4-pots. With the FHI 4-pots you get a smoother more consistent action than a 2 pot sliding caliper.

 

-Mike Paisan

 

http://www.pbase.com/paisan/image/91072632.jpg http://www.pbase.com/paisan/image/145749898/original.jpg http://www.pbase.com/paisan/image/133406601.jpg http://www.whiteline.com.au/images/logos/perf1.jpg

11+ Years Maintaining, Modifying and Educating TriState Subaru Enthusiasts.

Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs

"Race Tested, Enthusiast Approved!"

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I can see an issue with this setup in the same way I personally see the same issue with Brembo, Wilwood, or any fixed caliper braking system combined with stock LGT or any solid cast rotors. The stock LGT setup (as do just about every single street vehicle) relies on the sliding movement of the caliper to compensate for imperfections in the system as they are being used-i.e. heat variations, expansion and contraction, etc. Rotors that have a mismatched amount of friction material (improperly bedded) or that are actually warped on a minimal scale are compensated for by the sliding movement of the caliper with minimal to no feedback of pulsation in the pedal.

 

While generally the more pistons you have in the caliper part of your braking system contacting the plate side of the pads will give you more clamping power and to have pistons on both sides definitely can increase modulation, there are some drawbacks unless that same movement compensation is allowed for.

 

In order for a fixed position caliper to work correctly it requires some movement somewhere within the actual clamping portion of the system which in racing applications is handled by using a "floating" rotor. These rotors have the hat fixed to the hub by various means (bolted directly, held on by a center spindle bolt, held on by the wheel/lugnuts) but the actual rotor portion/friction surface floats (can move slightly back and forth on the mounting system) on various types of fastening bolts. The rotor being able to move accomplishes exactly what the sliding caliper does-it allows some movement to compensate for minor irregularities within the system when you apply the brakes. It also allows the rotor to be exactly centered between the pads when you release the brake pedal and the pads contract.

 

Lastly, if you have a fixed caliper system with multiple pistons and one of the pistons does not release as it should or cocks at an angle due to a seal failure or a crack in the piston, it can be inherently dangerous as it could cause a wheel to lock up or a possible release of fluid (which can happen with sliding calipers as well but it's not nearly as common) which can put you in a very deadly situation.

 

I know it's hard to believe (because I have difficulty myself believing it a LOT of times when I see how boneheaded some of the things that were designed in all cars are by engineers...LOL) but they actually do a LOT of testing when they design braking systems on cars. The manufacturer has an astoundingly high amount of liability thrust on them in any vehicle they put on the road and because of that, they do their diligence when they design a braking system.

 

Is it that we actually want more performance or is that we want to be able to show off our expensive brakes? I really believe that for the most part, it's the latter. If you take the stock LGT system, add good pads, good rotors, SS brake lines, and good fluid, you'll end up with a system that works at least 50% better than it did when you purchased the car.

 

The real question everyone needs to ask themselves is: Are there really that many people driving LGT that need more than that (40-50% increase), whether or not they actually track the car or just drive "aggressively" part of the time they are on the street?

 

Cost savings alone, the stock LGT system is a solid, well designed system that is simple to work on and inexpensive to repair.

 

These are only my thoughts and opinions on the LGT system however the fixed caliper/floating rotor stuff is something that we've dealt with for many years with various race cars and this is fact. Take a look at ANY road race car, F1, or car that is used for multiple corner, multiple direction racing and you'll never see anything but fixed caliper/floating rotor systems.

 

I personally run Centric Cryo blank rotors, HP+ Hawk pads, Goodrich SS brake lines, Wilwood EXP600 fluid, TiSpeed Ti shims and have absolutely excellent brakes with great modulation and virtually no fade. I'm sure that other systems have more clamping power but I don't have pedal pulsation and the car stops 40-50% better than it did stock (and I bought the car new so I have that baseline to compare to). The cost of EVERYTHING on the braking system is less expensive than front Brembo calipers sans pads but I don't have the ability to point at my front wheels and say "look, I have Brembos" and I can live with that and extra $$$ in my pocket.

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Interesting. While I agree that the stock brakes on the LGT are perfectly acceptable even for tracking. I found not a whole lot of difference between a good pad/line/rotor setup on stock v. Brembos in my 2 years of testing both setups on track with my 05 LGT. As for fixed calipers needing floating rotors, there are a lot of OEM setups out there that do not use floating rotors with fixed calipers so I'm not sure the tolerances are so tight as to require that anymore. (CTS-V, STi, Evo, Every Toyota Truck, Various Acuras, 135i, etc) all use fixed calipers and non-floating rotors.

 

-mike

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Interesting. While I agree that the stock brakes on the LGT are perfectly acceptable even for tracking. I found not a whole lot of difference between a good pad/line/rotor setup on stock v. Brembos in my 2 years of testing both setups on track with my 05 LGT. As for fixed calipers needing floating rotors, there are a lot of OEM setups out there that do not use floating rotors with fixed calipers so I'm not sure the tolerances are so tight as to require that anymore. (CTS-V, STi, Evo, Every Toyota Truck, Various Acuras, 135i, etc) all use fixed calipers and non-floating rotors.

 

-mike

 

I know what you are saying and I've seen most all of the vehicles you quote above. The issue on most of those is that it's done more for aesthetics than actual function. We both know that an STi with LGT brakes done correctly would stop extremely well (as how many WRX guys look to find LGT brakes in the junkyard as a huge upgrade?), most likely just as well as the Brembos, as would an EVO but they put the Brembos on these vehicles because of the proposed "high performance" aspect and appearance of the vehicle.

 

Issues with fixed rotors and fixed calipers really come to light when something like a front hub/bearing assembly has a major failure and all of a sudden the entire hub cocks 5 or 6 degrees at center and the extension out to the edge of the rotor then turns into 10 or 12 degrees, which allows it to hit the caliper, doing a lot of damage to all components and possibly even locking up the wheel.

 

Having had systems on race cars with floating rotors and fixed calipers, I can tell you that the efficiency is far superior to sliding calipers because (in an absolute perfect setup which we all HOPE we have) with pistons on both side of the calipers and equal pressure, the modulation is far superior as well as there is no caliper flex because the pistons are the "cushion" if you will, for the pads. That setup also is a far more efficient distribution of heat too as the outside pistons help dissipate along with the inside.

 

As I say, I really think that the sliding caliper design (stock LGT) is far more practical, more efficient, more effective on a street car that most of us, including myself (even though I call my car a track car, it's still just a modded LGT) would generally never need any more.

 

As I said in my earlier post, I think there is a LOT of the point and proclaim factor. "Look, I have Brembos" and everyone goes "ooooohhh, and ahhhhhhh" and then you can strut around for a while knowing that you impressed....LOL.

 

I've tracked my car with the setup I list above many, many sessions with virtually no fade or issues and I would rather keep my money in my pocket rather than go for the oooohhh and ahhhhh effect. Just my own personal opinion with not one thing held against people that want BBK.

 

YOU have access to a lot of stuff being a dealer/distributor. Put a kit together with floating rotors and try it yourself on one of your own vehicles. See exactly how much better it is and then maybe you can offer the setup both ways for people. I would bet that you'll sell a lot of the floating rotor setups first because they're really cool, and secondly because they really will work better.

 

:)

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YOU have access to a lot of stuff being a dealer/distributor. Put a kit together with floating rotors and try it yourself on one of your own vehicles. See exactly how much better it is and then maybe you can offer the setup both ways for people. I would bet that you'll sell a lot of the floating rotor setups first because they're really cool, and secondly because they really will work better.

 

:)

 

Agreed 100%, our philosophy is to not sell anyone anything they don't need or wouldn't benefit them. Going with that, floating rotors would be well beyond the capability and needs of 99% of the Subaru drivers out there, especially our street driven customer cars. Heck I've been instructing for 10 years in both DE and Racing and I never felt the need, on my LGT to have such stopping power available to me. Our time and resources are better suited to continuing to find better deals and put together better packages that would effect a larger number of our constituents. :) Besides, Ken at KNS does a pretty efficient job of R&D (was a brake engineer in MI many moons ago) so I leave that stuff to him. I'm sure this package is setup as a compromise of money v. performance.

 

-Mike Paisan

 

http://www.pbase.com/paisan/image/91072632.jpg http://www.pbase.com/paisan/image/145749898/original.jpg http://www.pbase.com/paisan/image/133406601.jpg http://www.whiteline.com.au/images/logos/perf1.jpg

11+ Years Maintaining, Modifying and Educating TriState Subaru Enthusiasts.

Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs

"Race Tested, Enthusiast Approved!"

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Ok guys just picked up a set of Aluminium 30mm Calipers for $100 locally. Waiting for brackets and I am going to test fit Subaru brake lines.

 

http://i131.photobucket.com/albums/p318/FLCLgibson1968/image_zpsbe6150ef.jpg

 

http://i131.photobucket.com/albums/p318/FLCLgibson1968/image_zpsa58d3710.jpg

 

http://i131.photobucket.com/albums/p318/FLCLgibson1968/image_zpsd4b3b84b.jpg

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