240SX Brake Upgrades:
Brakes upgrades for the 240sx are a relatively easy modification, as pretty much all the brakes from the bigger and faster Nissans bolt right on. Skylines, Infinity Q45’s, 300ZX...all their brake calipers bolt on with as little modification as cutting away the heat shields, and in some cases, replacing the brake lines (it’s recommended that you use steel braided lines, such as Goodridge) And for those of you with 4-lug 240’s, you’ll need to get the rotors re-drilled to fit...but that’s as complicated as it gets.
The brake swap that’s most common is the Z32 brakes from the 300ZX. These are better because they’re bigger (11 inch rotors that are 30mm thick) and because the calipers are of the 4-Piston variety...not wimpy 1 piston sliding calipers like the stock ones. See below for instructions/pricing on this upgrade...
Another GREAT upgrade is the Q45 brakes offered by Nissan Motorsports as their "240sx Big Brake Upgrade". These are thought to be less exotic (but are usually less expensive), but more people go for the 300ZX swap. I like the Q45 swap better, so I those on thge front (and now Z32 brake son the rear to match...hehe). The Q’s calipers are a 2-piston sliding design, and the rotor is almost identical to the 300ZX at 1.1inches thick and 11 inches in diameter. The larger pads have about 40% more surface area, and the two pistons will give about 25% more clamping force for the same amount of pedal pressure - So these are a lot stronger than stock...not to mention better heat capacity, fade resistance, etc...
You can buy the Q45 set up as a package (from Nissan Motorsports
(310)538-2610 – Price: $900), or you can go to any
Infinity dealership and order the parts you need...You’ll be hard
pressed to find a Q45 in the junk yard, but after a month or searching,
300ZX Front Brake Swap
What you need to know:
There are different calipers and different rotor sizes for the Normally Aspirated and
The calipers come in Aluminum and Cast Iron, and the rotors are either 26mm or 30mm thick.
See the chart below for the year and size differences...
Wheel clearance is something BIG to consider: 4-piston calipers extend out from the spindle much farther than the stock brakes...I’ve heard of many people with nice, light aftermarket wheels having to buy new ones after getting bigger brakes... Using wheels that will fit a 300ZX is good enough to know they will clear the calipers, but the offset/backspacing may be such that the tires will rub the struts when you turn the wheel. There is no definite answer here, but most 16-inch and larger aftermarket wheels with the proper offset for a 240sx **should** work.
When putting 300ZX brakes on your 240sx, you’ll need new brake lines...the fittings on the calipers are different for the Z brakes. The thread/pitch/style of the fittings for the 300ZX NA/TT front calipers are:
For the caliper side: 10mm X .1mm - Male - INVERTED METRIC FLARE
For the chassis side: 10mm X .1mm - Female - INVERTED METRIC FLARE
You can buy SS lines from PDM Racing, or have some made if you like...or you can uyse the 300ZX lines IF you get the rubber line AND the hard line that goes to the calpir... you will need both pieces per side to make this work.
Remember to re-use your stock caliper bolts, as the 300ZX bolts are longer and will hit the back side of the rotor.
There are 2 good ways to do this swap:
1) Order it up from PDM Racing, and you’ll get rebuilt calipers (powdercoated black), new cross-drilled rotors,
high quality pads, and new stainless steel lines…all for the low-low price of $1000!!!
2) Or you can hunt your local junkyards for parts - Here's the breakdown on the various 300ZX calipers/rotors over the years, according to Nissan Motorsports:
|Non-Turbo calipers, rotors:||Turbo calipers, rotors:|
|Up to 7/90 – Aluminum, 26mm rotors||Up to 6/92 - Aluminum, 30mm rotors|
|8/90 to 3/92 - Aluminum, 30mm rotors||7/92 to 1996 - Cast Iron, 30mm rotors|
|4/92 to 1996 - Cast Iron, 30mm rotors|
Keep in mind that weight is a big factor here, being that it is un-sprung and rotating mass...but it is a necessary evil. Bigger, heavier rotors can absorb more heat, thereby allowing your brakes to remain effective for a longer time...
|Stock 240SX||300ZX Turbo||Slyline GT-R (R34)||Infiniti Q45|
|Rotor Diameter:||10 inch||11 inch||11.6 inch||11 inch|
|Rotor Weight:||12.5 lbs||17.5 lbs||19 lbs||17.5 lbs|
|Caliper Type:||1-piston sliding||4-piston fixed||4-piston fixed||2-piston sliding|
|Caliper Weight:||9.5 lbs||6.5 lbs (alum), 10lbs (iron)||6.5 lbs||11 lbs|
Other options for stopping faster are:
High Performance Brake Pads:
There are many high performance pads available for the 240sx, and most are well worth the higher price compared to auto parts store OEM replacement pads...and OEM pads will probably cost the same or more than the best high performance pads. (Axxis Metal Masters pads are excellent for the street/track, as are EBC Green Compound and Hawk Pads...)
Changes in Brake Fluid:
Stock 240’s must use DOT 3 fluid or better, which isn’t bad, but to avoid fluid boil at
high temperatures after lots of hard braking, use a fluid that exceeds DOT 3
and DOT 4 specification, such as Castrol GT-LMA or Ford High Performance Brake Fluid.
I actually prefer and use Valvoline Synthetic fluid...
(NOTE: On a street car, DOT 5 Silicone fluid is overkill...It’s virtually impossible to remove all the air from the brake lines due to the properties of silicone, it’s incompatible with regular fluids, and you may have to change all your rubber seals, etc...You will regret using it)
Cross Drilled / Slotted Brake Rotors:
There are many advantages in buying performance-oriented rotors...specifically less fade under repeated hard braking. Cross Drilled rotors also help out in the rain by wicking the water out from between the pad and the rotor. Slotted Rotors (most of which are also available cross drilled) help even more under extra-hard braking by allowing the release of gasses that form between the pad and rotor (which effectively push the pad away from the rotor...) thus allowing the pad to stay in constant, even contact with the rotor.
Infiniti Q45 Brake Upgrade
The ’90-’96 Infiniti Q45 is a V-8 powered 4100 pound beast requiring LARGE brake to stop it safely.
Luckily for 240sx owners, these big brakes bolt right on - all you have to do is remove the heat shield.
Q45 brake calipers have 2-pistons (43mm each compared to a single 54mm piston on the stock calipers), the rotors are 11 inches in diameter and 28mm thick, the larger pads have about 40% more surface area, and the two pistons will give you about 25% more clamping force compared to the stock brakes...
When I decided to do a brake upgrade, I was lucky enough to find a wrecked 1995 Q45 in the junk yard with very low miles. I thought that it was best to use new rotors, and I found the price for OEM replacement rotors were so close to the price of Powerslot rotors, I chose to buy high performance.
Why did I choose this over the 300ZX brake upgrade? Mainly because of the lower cost of the calipers. Pads and new rotors (especially high performance rotors) will cost about the same with either setup.
...and with the Q45 calipers you can use your stock brake lines - Another part of the lower cost.
As far as stopping power, fade resistance, etc... I would put these up against the 300ZX brakes any day. (I have road raced with these couped with Z32 rears and have had NO fade). 4 piston fixed calipers from the Z will feel firmer at speed (especially with the required new SS lines), and look "cooler" because the Nissan logo is painted on the side...but if you believe form follows function and/or you want to do something different, this is a perfect way to go.
Tools you’ll need:
Deep well sockets - 12mm, 19mm
Brake Fluid - You must use DOT 3 or better, I chose Castrol GT-LMA (exceeds DOT3 and DOT 4 specs...)
Catch Can - FOr bleeding the brakes - Coffee can is perfect...
Clear Plastic Tubing (1/4 inch - Ithink)
Tin Snips (to remove the heat shield)
A couple feet of rope - Used to hold the old caliper out of the way...
How long will it take?
This was my first time doing a brake swap, and it took me and a friend 2.5 hours from start to test drive, including cleanup.
Where do I start?
Jack up the front of the car, and support it on jack stands.
Remove the front wheels, and place them aside.
Remove either caliper from the spindle by removing the two 19mm bolts on the back of the caliper.
Tie the caliper to the strut to keep it out of the way until you’re ready to change the line from the old caliper to the new one...
Remove the old rotor by tapping it gently from the back, or use a bolt in the hole that's drilled/tapped in the rotor near the lug holes...
Now’s the fun part - Removing the heat shield. You can get a large pair of tin snips, or use a cutting wheel, but whatever you do, don’t damage the hub, and if you have ABS, be sure you don’t damage the sensor or its mount.
Now your ready to begin the install:
Put the new rotor on the hub and use a couple of lug nuts to hold it in place.
Place the new caliper (loaded with new pads) onto the spindle and bolt it in place. Tighten to 75 ft/lbs.
Unbolt the brake hose from the old caliper by removing the 12mm nut and the copper washer.
Quickly place the line on the new caliper (don’t lose the copper washer) and tighten to
spec. You will lose some brake fluid...
Remember how harmful brake fluid is to paint - It destroys it on contact!!!
Untie the old caliper from the strut and place it aside...
Check to see if the new caliper slides freely, and that the new rotor spins freely.
Now you’re done with one side. Do the other side, and bleed the brakes, making sure to keep the master cylinder full (Start with the caliper farthest from the master cylinder - the left rear...)
Be sure to bed the pads! This means that before you test your new brakes, you need to go out of your driveway, accelerate to 60mph, gently apply pressure to the brake pedal until you slow to 5mph, then accelerate to 60 again, brake slowly, etc... Repeat this procedure at least 10 times...the pads should smoke and burn off all the molding agents, etc...used in making them.
Drive gently on your new rotors for the first 500 miles to break them in - After that, go out and amaze you friends with your new stopping power - But be careful if you don’t have ABS...
It's much easier to lock them at lower speed...I can now lock my brakes at 30mph. You also might notice a slight loss of brake pedal travel and less braking modulation...that’s from using larger calipers with the stock master cylinder. It’s not harmful, but it will cause the brakes to be VERY sensitive. If you stomp on them, they will lock up. Period.
I hope your install goes as well as mine - If you have any questions, e- mail me at email@example.com.
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