Help with q45 brake upgrade.

[hazukijitsu]

I was driving around today and realized that my brake pedal was starting to get mushy, popped the hood and found some brake fluid leaking from the Brake Master Cylinder and on to the brake booster. So I was thinking about doing a Q45 brake upgrade from a parts car at my Uncles junkyard (woo-hoo free(ish) parts!). So with this in mind, can I use the Brake Master Cylinder from the Q45? Is it necessary to have it to push more fluid? Also, I heard that the the Q45 brake upgrade is a mostly bolt on affair and that I need to either redrill my rotors to fit 4 lug , but I have also heard that Altima or Sentra SE-R rotors will work. Does anyone have any testimonials on this?

The most important thing I need to know is that if the Q45 BMC will work on my s13.

[anti_flag_army]

no clue on the BMC, the stock one works just fine with those calipers. Yes they just bolt right on, and i have heard about the rotors, but what i have heard is that they arnt thick enough and that if the pads wear enough that you risk the pistons comming out.

[rico05]

Altima and SE-R rotors are too thin. I was lucky enough to be a manager of a parts store when I initially did this 2 years ago so I spent a lot of time measuring. I finally settled and had a machinsit buddy of mine redrill the Q rotors to 4 lug.

The calipers bolt right on, but you have to cut and bend the dust shield out of the way.

The BMC swap is not necessary. Just get a new S13 one from the parts house.

[ILoveMyRHS13]

Okay, here goes; REMEMBER THIS DAY NICO, I'm helping.

As for the BMC, get one from an 89 300ZX turbo (Z31). It's the same shape as a 240sx one but has a larger bore, therefore pushes more fluid.

As for brake rotors, get ahold of Travis@88Rotors on Zilvia and tell him you want Q45 rotors RE-DRILLED to 4x114.3.

[ray666]

i was thinking of doing this swap. i just don't know if my wheels can handle larger calipers. there 16" xxr's with 0 offset. think they'd fit? i guess i could go j30 if the q's don't work.

[LambJerky]

If you have a Q45 BMC, it will work, not sure how difficult the job is.

Z32 BMC is a good option too, I have one sitting around somewhere I'm gonna use on my s14. From the looks of it it may be tricky but not difficult, so I would assume a Q45 is not much more difficult.

[ILoveMyRHS13]

i was thinking of doing this swap. i just don't know if my wheels can handle larger calipers. there 16" xxr's with 0 offset. think they'd fit? i guess i could go j30 if the q's don't work.

Q45 brakes will clear stock steelies... It's rumored that they won't fit teardrops, though. I haven't tested this or not.

[OutToWinPAHC]

If you have a Q45 BMC, it will work, not sure how difficult the job is.

Z32 BMC is a good option too, I have one sitting around somewhere I'm gonna use on my s14. From the looks of it it may be tricky but not difficult, so I would assume a Q45 is not much more difficult.

Dont use a Z32 BMC with the Q fronts. The bias is set up for 4/2 pistons. I have heard of people using the Z31 BMC before, some even use it with Z32 brakes.

So use a S13/S14 BMC or get a Z31

[LambJerky]

Dont use a Z32 BMC with the Q fronts. The bias is set up for 4/2 pistons. I have heard of people using the Z31 BMC before, some even use it with Z32 brakes.

So use a S13/S14 BMC or get a Z31

Oh, no that is not what I meant. I didn't mean to say to use the two together. I was only comparing the difficulty level of installing them.

I just recommend using parts from the same car itself.

[matt4pl]

Q45 master cylinder won't work... it only has two ports because it's made for an ABS system. Z32 will work though, or stock, 1st time I've heard of using a Z31 BMC though

(i have q45 calipers and a z32 master)

[maj Andres]

THe Z32 one also has two ports. Unless you get lucky and get one with the 3rd fitting installed.

[diggles240]

Z31 has a better brake bias supposedly. I do believe a lot of people use it.

[LambJerky]

Q45 master cylinder won't work...

I stand corrected on using Q45 BMC with Q45 calipers. I was only going based on what I have read from other builds with this setup

Yet, anything will work with some ingenuity.

[AZ89two4Tsx]

Ok here.

- Keep your stock master cylinder, it will work fine with Q45s up front

- ONLY use Q45 rotors. Don't chance something like that, they're cheap

- Make sure you get the caliper mounting bolts. They are soooooo hard to find, and you'll have to order them from the dealer. J30 bolts will work too

- Get the rotors drilled at a machine shop, don't use a drill

- They are bolt-on other than the dust shield

- Q45 brakes fit almost every wheel out there. Much lower profile than Z32 onesk

[Warped161]

Ok here.

- Keep your stock master cylinder, it will work fine with Q45s up front

- ONLY use Q45 rotors. Don't chance something like that, they're cheap

- Make sure you get the caliper mounting bolts. They are soooooo hard to find, and you'll have to order them from the dealer. J30 bolts will work too

- Get the rotors drilled at a machine shop, don't use a drill

- They are bolt-on other than the dust shield

- Q45 brakes fit almost every wheel out there. Much lower profile than Z32 onesk

confirmed

[ray666]

thx for the info

[rico05]

I get my fronts to lock up fairly easy with the standard BMC, so I would be very cautious with upgrading.

[ILoveMyRHS13]

Z31 has a better brake bias supposedly. I do believe a lot of people use it.

Ding ding ding!

And if you're locking up your brakes that easily, you need to learn how to drive. I just went out and sat my rotors and pads together a couple weeks ago and didn't lock them up once.

[ray666]

i have to ask, how you are locking your brakes so easily? i haven't heard of anyone having that kinda trouble.

[diggles240]

i have to ask, how you are locking your brakes so easily? i haven't heard of anyone having that kinda trouble.

It is very simple. If you want to lock up your brakes, it is very easy to do (without ABS). Do not forget that stopping power is very dependent upon tire grip, i.e. crappy tires = easy lock up.

[ray666]

i guess i'm gonna go j30 then cuz i don't have abs

[rico05]

I can avoid locking them up just fine. Not an issue of skill by any means. Try watching a Grand Prix some time and tell those chaps they have to learn how to drvie.

I run a harder tire for the street and in certain conditions, the fronts are easier to lock up than stock.

[wanganss13]

I get my fronts to lock up fairly easy with the standard BMC, so I would be very cautious with upgrading.

Maybe you need to rebuild or service your calipers, my cousin had a similer problem and he needed to rebuild them.

[rico05]

Brand new BMC and fully rebuilt calipers, new pads and rotors. Goodridge lines.

I am lost. I think that everyone read that I lock my brakes up at every stop light. I have been autox'ing since most of you were too young to drive yourself to Fast and the Furious. Just simply saying I do not feel in my experience that a larger diameter cylinder is necessary. If you do the math and you can justify it, super great. I didn't. I can lock up the fronts when I would not lock up the stock brakes. Just a simple statement. Let's move on with our lives.

[diggles240]

i guess i'm gonna go j30 then cuz i don't have abs

Not true at all. Do not shy away from the Q brakes because of the increase in stopping power. By my statement, I meant only that one can lock up the brakes if they want to (not like you would want to do that). You just have to learn how to properly brake.

Listen to rico05

[ray666]

I'm keeping my options open i just got my car motor swapped and need some reliable stopping power. are the q45's way better than the j30's?