Skyline Brakes Upgrade on Q45 - Need Help

[rsiwicki]

I am interested in upgrading the brakes to the Skyline system.

Does anybody have this already done and was there a noticeable difference?

Also does anyone know of a source where I can buy the Skyline brakes for my car that includes everything (rotors, calipers, ss lines, etc.)

Are there any issues with wheel clearance of the calipers....do the skyline require a bigger wheel other than OEM size?

[AZ94Q]

Goto stillen.com, and look up the 300zx. You will see a skyline brake upgrade, on the last page. It's the same kit they offer for the Q. I think they are the only ones who are offering the kit specifically for the Q IE they modify it to fit..

you could buy the parts individually, and jerry rig them yourself, I suppose..

You need at minimum 16 inch wheels. It's designed to fit with stock 300zx wheels.

[dutch boy]

Is it possible to fit the 350Z brembo's on a 97 Q45T ?? they look similar and need only brake lines???

[911/Q45]

I put the Skyline kit from Stillen on my car and it fit great. I did have to remove the backing plates from the hubs. The rotors now last forever. The only drawback is they are prone to squealing unless you use factory 300ZX pads and shims, also a little growl from the drilled rotors during hard stops. The pads don't incorporate the Q warning sensors, so you have to jump those wires and visually check pad depth once in a while.

[SeattleQ45]

I need new brakes soon for my '94 Q45. I've seen Skyline and Brembo kits mentioned here. Any thoughts one other options besides factory kits?

I'm concerned about better stopping and freedom from warped rotors...I've had this problem with a Maxima and an I30, and don't want to deal with that on my Q45 too. Maye my driving and braking style cause this, but I haven't tried driled or slotted rotors before.

[rsiwicki]

thanks all for you comments on the brakes.....from Stillen for the entire kit which includes everything (ss lines, front & rear calipers, rotors, pads, etc.).

911/q45 guy told me that is was difficult to really know how much the brakes alone helped as he put new wider tires & brakes on at the same time.

Maybe Q45tech has a comment or two for us on how much of an improvement we can expect in our ability to bring a 4,000+ lbs car to a stop.

I probably will be getting the kit, but in about 2 months or less after I get some other things done and make sure my car is running smoothly.

[Jeff Williams]

I found a mod kit, for putting the 12.5" rotors off a Mitsubishi 3000GT, on a 300ZX. It looked very simple, but I never did anything about it.

I saved the document, and it had this along with pictures:Z-Improvement Procedure

TITLE: Procedure to Install 12.5” Brake Conversion Kit LEVEL: 0 Maintenance 0 Manufacturing 0 Operation 0 Reliability 0 Safety 1 Upgrade 0 Retrofit 0 Hardware 0 Software 0 Other 0 Documentation Update

Description: This procedure contains assembly process and required tooling to perform 12.5” Brake Conversion Kit installation

Disclaimer: The 12.5” Brake Conversion kit is not intended for street use. Use this product at your own risk.

Required Tooling and Parts1) Lug Wrench2) 19 mm Combination Wrench3) Metric Socket Set4) 12 mm Combination Wrench5) Sheet Metal Cutters6) Torque Wrench7) LocTiteâ 2428) 12.5 Inch Brake Rotorsa. Mitsubushi 3000 GT VR-4 1994-1998 (Not Included)

Material List:Part Number Quantity Description1 2 Caliper Mounting Brackets2 4 M12x1.25x30 Grade 8 Hex Head Bolts3 4 M12x1.25 Nuts4 12 12 mm I.D. Washers

Installation Procedure:

I. Jack up cara. Apply Emergency brake.b. Jack up car.c. Ensure car is on level surface and securely supported with jack stands before continuing.

II. Remove Front Wheel

III. Caliper and Rotor Assembly Removal

a. Using 12mm wrench, remove two bolts holding brake line support bracket to rear of spindle.b. Using 19mm combination or socket wrench, remove the caliper mounting bolts.c. Slide brake caliper off rotor and set aside.i. Note: Be careful not to allow brake caliper to hang by the brake line.d. Pull brake rotor off of wheel hub.e. Using Sheet metal cutters, remove brake rotor heat shield.i. The spindle following heat shield removal is shown in figure 1.

FIGURE 1

IV. Bracket Installationa. Remove the original flat washers from stock caliper mounting bolts.b. Replace with washers supplied in kit.i. Note: 1 washer per bolt.c. Slide original caliper mounting bolts thru caliper mounting bracket as shown in figure 2.

FIGURE 2

d. Install caliper mounting bracket into spindle.i. Apply Loctiteâ 242 to bolt threads.e. Secure bracket using 2 flat washers and 2 - 12 mm nuts.f. Tighten caliper bracket mounting bolts to 72-87 ft-lbs.g. See figure 3 for installed bracket.

FIGURE 3

V. Caliper and Rotor Assembly Installationa. Slide new 12.5 inch rotor onto wheel hub. See Figure 4.

FIGURE 4

b. Slide brake caliper onto rotori. Apply Loctite 242 to bolt threads.ii. Mount to caliper bracket using 2 - M12x1.25x30 bolts and washers. See Figure 5.

FIGURE 5

c. Tighten caliper mounting bolts to 72-87 ft-lbs.d. Using 12mm wrench and original mounting hardware, re-attach brake line support bracket to rear of spindle.i. Note: You will have to slightly bend steel brake line between caliper and brake line support bracket. See Figure 6.

FIGURE 6

VI. Re-mount Wheel.VII. Repeat Steps I – V for Second Wheel.

Contact Information:E-mail [email protected] if you have questions regarding the installation procedure.

[Q45tech]

Rotor weight [90% of ability] and air flow during the braking [doesn't help much in a single stop time too short].

The newer LS430 has 23 pound rotors so that might be a guide.

Based on a pure rotor weigh RATIO, the rotors should be 25% cooler for the same stop.

The problem is racers want low unsprung weight for handling while big trucks want heavy rotors. Many of these aftermarket kits give up rotor weight.

The new QX56 has 26 mm x 12.6" for a 5600 pounder whereas the BMW 745 has 13.7" x 32mm same thickness as LS.

350Z Brembo = 12.76" x 30mm vs standard G35 11.65" x 24mm.

I just don't understand why Infiniti uses such thin rotors, but weight is not necessarilly directly related to thickess as the air vents could be smaller in width.

In my opinion anything less than 32 mm [front] would be a waste of time and resources for the Q........32mm is only 14% thicher compared to 28mm.

The 11 x 30mm used on the old 300zx tt wouldn't do much if anything compared to 11 x 28mm oem on Q

[rsiwicki]

thanks Q45tech for your help...while the first part of your response was a bit over my head...I understood the last part that I need at least a 32mm front rotor to make it worth my time and monies....

[AZ94Q]

How thick are the skyline rotors? Remember, the skyline brake upgrade, has thicker rotors then the standard 300zx kit... It's designed as an upgrade for the 300zx, as well as the Q..

It sounds like q45tech thought these were just 300zx brake kit for the Q45... They are a skyline brake upgrade for the 300zx/q45... Based on what other members are saying that have them, and the fact they were used on a racing Q, I think they are a good setup...

Wouldn't mind the Brembo Ferrari F40 brake upgrade for the Q. To bad it's like $3,500 for the fronts only...

[HeavyDuty]

Wouldn't mind the Brembo Ferrari F40 brake upgrade for the Q. To bad it's like $3,500 for the fronts only...

I have a pair of F50 calipers, I believe. They haven't used the F40's in a while, hard to tell the difference from first glance.

All one would need is the parts from Stillen, I already have a breakdown, $1100 cost on what it would take to make my calipers work with the rest of their kit. They might be for sale if anyone's interested.

[Q45tech]

Even rotor thickness cannot be counted on.........as to save weight there may be just more air space in the vent.

The Q has 9mm per side of metal, what you want is at least 11 mm per side plus 10 mm or less of air space.

Unfortunately aftermarket does not think HEAVY, because so many think they want a LIGHT rotor for acceleration.

[rsiwicki]

help with a setup still needed.....

I have a contact from over in the Skyline thread that might be able to hook me up with the Skyline calipers and rotors, but I need to know exactly what kind of setup I need to make this thing work.

I know Q45tech mentions that I need at least a 32mm rotor and a heavier rotor to deal with the heat. The Stillen conversion uses Skyline 4 calipers (fronts) and 300zx 2 calipers (rear). I don't know about the Stillen rotor size, but I do recall them saying that it was just the same rotor size as the 300zx rotors.

Also would it be beneficial to go to a 4 caliper front and rear setup or just stick with 2 calipers for the rear?

[Jeff Williams]

I would be concerned about front/rear bias.

Whenever we upgraded the brakes, on a old disc/drum stock car, to disc/disc, for the track, we would add a bias control, or pressure regulator, to help adjust the front to rear pressure offset. It was kinda trial and error setting. Once we went big-time, we had a bias control knob in the ****pit, that the driver would adjust during the race, as the brakes got hot, and the track changed, or we went to different tracks, where braking requirements changed.

I would stick with a standard set-up, since the car already has a bias control in the lines, or the master cylinder has one built-in.

If you get too much braking ability on the rear, you will ahve no control over the car, in a hard stopping condition.

[QShip]

I would be concerned about front/rear bias.

If you get too much braking ability on the rear, you will ahve no control over the car, in a hard stopping condition.

Great point! I didn't think of that.

[Q45tech]

Except that the ABS will kickin increasing the braking distances from what is possible if perfect bias was achieved.

Nice to have the braking system already tuned within 10% and the ABS to correct for ambient temperature changes and the tire temperature as it changes over the 3-4 second stop.

The fewer ABS cycles per second the shorter you stop.

ABS is not allowed in most racing events.

The Q already uses some of the most aggressive REAR braking bias [known on a RWD car]. How they got the 129 feet [14 years ago].

I'll bet that with the pads and tires most use today 150 feet [or worse] might be average.

The rear pad compound [u85] hasn't changed as much as the front pad compound [u90>u91>u93 as supplied by dealers for replacement] due to dust and wear compliants.

Find a seriously fast wearing dusty pad for the fronts and you will probably out brake any $2,000 aftermarket caliper kit [at least in single stop 80 mph panic stops.

[Jeff Williams]

Does the Skyline kit eliminate the ABS?

[rsiwicki]

thanks for you alls comments.

I spoke with Stillen and it does not bypass the ABS system. The ABS system generally will not be affected when switchinng calipers and rotor size as long as you maintain the same tire diameter as the ABS system is highly sensitive to OEM tire diameter.

[HeavyDuty]

Correct me if I'm wrong, but the fronts perform 80% of the stopping duty, so I see no need for 4 pot rears.

Single stop data is one thing, but even with my lightweight BBS wheels, more than once or twice with little cool down time (highway stop & go) leaves me wanting more braking capability. When I change out to the heavier wheels, I'm sure it's going to get worse.

[rsiwicki]

Heavy...that is my concern also, going to the 18" wheels will definetly add a lot more forces on the brakes. Also after I get the JWT ECU, new transmission, and 4.08 I have a feeling that I will need the extra stopping power at the higher interstate speeds that I will be traveling.

[AZ94Q]

The skyline brake upgrade, has 2 piston rears, 4 piston fronts...

1 piston rear is not enough..

Come to AZ, and I'll show you what happens to stock brakes

Give me upgraded brakes any day.

I believe a big brake kit would reduce the 129 feet drastically

A stock XJR brakes from 60-0 in 129 feet (non brembo)

WIth brembo brakes=116 feet

That's a major difference.. Same tires. just better brakes

[maxnix]

Correct me if I'm wrong, but the fronts perform 80% of the stopping duty, so I see no need for 4 pot rears.

Single stop data is one thing, but even with my lightweight BBS wheels, more than once or twice with little cool down time (highway stop & go) leaves me wanting more braking capability. When I change out to the heavier wheels, I'm sure it's going to get worse.

While 4 piston rear calipers will have more even pressure and aid in spirted driving conditions (like down a mountain road), the real concern is the heavier wheels and their effect on braking performance. One of the few (perhpas only) reason to utilize an 18" wheel is to get the largest rotor possible, particularly on the front.

I personally would prefer a vented rear rotor of at least the J's capacity.

[Jeff Williams]

I go through 2 sets of rear pads, for ever 1 set of fronts, on my Q.

I would like to upgrade to just the stock 300ZX brake calipers, if possible. I could get these, relatively cheap.

They look to be a little better than the stock Q's. I have not looked at them closely.

[rsiwicki]

Ahh good another person who goes through the rear brakes twice as fast as my fronts. I have replaced the rear brakes twice...both pads and rotors in the last 47,000 miles and I can't figure out why my fronts don't need to be redone. I did my front pads over 60,000 miles ago and the rotors about 50,000 miles ago. They said that I had about 6,000 miles left on the front when I had the backs done about 1,500 miles ago. I can't figure for the life of my why the fronts are lasting so long as I drive very hard and the dealer said everything was operating correctly.

Either way...I feel some new brakes are on the way for me after I get all the other mods done as I want to be able to stop more quickly to avoid an accident and protect my new investment.

[Onizuka]

240sx people use the Q45 brake upgrade as a cheap alternative to the 300zx upgrade, so im assuming all these calipers are interchangable. If you want higher capacity rotors with 300zx front calipers this is a fairly cheap kit:

http://ztuner.com/brakes.php

You would need 17 inch rims with those (I measured and it wont fit any of my 16 inch rims).

[rsiwicki]

thanks for the info...I emailed them to get the specs on the calipers and rotor size, weight, and thickness as I did not see this listed on the website.