My Manual Brake Conversion

[float_6969]

http://www.horsepowerfreaks.com/perform ... Brake_Pads
my google skilz > ur google skilz

[alms24sebring]

With a decent set of pads, rotors, and ATE super blue, even stock binders hold up to suprising abuse.

I could agree with this

^ Hawk pads are the poop. Had them on my 240 with Rotora slotted rotors and they were great (when at temp).

[ska69]

thanks float It was more of request on your opinion than my laziness to google lol

[float_6969]

LOL! My bad. I'm currently running Wagner brake pads. They're NOT a race pad, but they came with the brakes, so we'll see how they hold up to some abuse.

[SolaraOnBronze]

I'm interested to see how this turns out. I am in the process of installing the Chase Bays booster delete and in-interior line tuck right now, but I won't have the bay completed and the car back together for a while still. Should be interesting!

[float_6969]

I should have results tonight. The speed bleeders came in yesterday and the parts for the brake lines came in yesterday, but the guy that makes the lines was sick. He's supposed to be back today though so I should have them this afternoon.

[ska69]

iirc my calipers came with those pads as well.
did you get Russel speed bleeders or some other 10*1mm bleeders?
I'm looking into getting those too. post up some pics of them & part numbers please

[float_6969]

Well no dice tonight. I got the lines and bleeders today. I went to install everything and forgot I needed new crush washers. I had to go to 3 different parts stores to come up with the 8 washers I needed. Stupid. Anyway, I got back home, installed the lines and went to install the speed bleeders and realized that Advance Auto has the wrong info in the computer and the ones I have are too short!!!! They have Dorman PN 12706 listed for use in S14's, but it should be Dorman PN 12709. Luckily they have them in Kansas City (I live in Topeka) and they'll have them here tomorrow morning. It's too dark for pics now, but I'll have more pics of the lines and bleeders tomorrow. I'm also going to finish putting the poly bushings in the control arms and spindle in the rear tomorrow too so all of my bushings will be done.

[float_6969]

OK, I got all the bushing in the rear done. Never want to see another poly bushing again in my life! LOL, anyway, I got the brakes bled and took it for a spin.... I don't like it. I sized the brake master too small. I can lock the brakes up, but the pedal is almost at the floor when it happens. The pedal is way too easy to push too. I think my 9 yr. old daughter could lock the brakes up on this thing. I will say the speed bleeders were awesome! Well worth the money. Soooo, I'm gonna call Wilwood on Monday and get a 7/8" master cylinder and see where that gets me.

[IanS]

OK, I got all the bushing in the rear done. Never want to see another poly bushing again in my life! LOL, anyway, I got the brakes bled and took it for a spin.... I don't like it. I sized the brake master too small. I can lock the brakes up, but the pedal is almost at the floor when it happens. The pedal is way too easy to push too. I think my 9 yr. old daughter could lock the brakes up on this thing. I will say the speed bleeders were awesome! Well worth the money. Soooo, I'm gonna call Wilwood on Monday and get a 7/8" master cylinder and see where that gets me.

I agree with you on the bushings, I have done 2 1/2 sets total, and Im sure they wont be the last. Ish


Are you sure master size is your only issue? Could it be, that by moving the lever point of the actuation rod you changed the behavior of everything?

By shifting the lever point closer to the pivot, you increase the amount of travel required to move a given amount of fluid. You increased your lever. You have to push further, and have less resistance. If you shift the actuator closer to the pad and decrease the lever it should increase the resistance, and decrease pedal travel.

Its been a while since I looked at the S chassis brake pedal in car, but something else to keep an eye on. The location on the pedal is chosen specifically to keep the path of the actuation rod as linear as possible. By moving away from this point, you could be putting undue stress on the master, thereby causing premature failure. I have seen this done on custom race setups. There is nothing cool about blowing out the seals on the master with no booster to isolate you from the fluid. Boiling hot brake fluid being sprayed on the legs and feet is no bueno, especially mid race. But like I said, I have no idea how the pedal behaves in car. Just something to think about.

[float_6969]

After driving it around some more today, the pedal doesn't go to the floor, but it goes further than I want it to. I know what the pedal ratio/travel relationship is. I could build another adapter plate and move the master down to use the stock hole, which will definitely lift the engagement point back up higher, BUT I also loose leverage, and pedal effort will increase as well. There was A LOT of time and effort that went into placing the master cylinder in the right place in relation to the hole on the brake pedal. If others don't know, the rod going into the master has to enter the master straight in. If it gets too far off from that, it will damage the master, like Ian said.

I might try to build another adapter plate this week before I order another master, but replacing the master with the next size up is WAY less work than a new adapter plate, LOL. But if it works, it'll save me $75. I'll keep this thread updated with my progress.

[ska69]

any updates?

so dorman makes speedbleeders?

[float_6969]

Nothing yet. The last time I drove it, the turbo melted the line going to the wiper fluid spray nozzle, the nozzle it self, and slightly deformed the brake fluid reservoir. So I ordered a turbo blanket, wrap for the down pipe, and some thermal insulation to make a heat barrier for the exhaust manifold. Once I get those in and don't have to worry about stuff melting again, I'll move forward with the new adapter plate to use the original brake pedal hole.

I did get the Dorman Speed Bleeders in and they worked awesome. I had the car on jack stands with all 4 wheels off, and with my wife in the car pumping the brake pedal, it took maybe 15 min to bleed the entire system (it had been drained of all fluid)

[ska69]

oh nice! didn't know they make speed bleeders!

he-he I guess top mount turbo dictates some new rules

[Razi]

Speed bleeders are so awesome.
<3

[float_6969]

he-he I guess top mount turbo dictates some new rules

LOL, yes they do. There have been quite a few times that I was ready to say f***-it and go back to a stock manifold and an S15 T28 and call it a day. But then I think about 400hp and go back to breaking my knuckles open and melting things.

Speed bleeders are so awesome.
<3

I agree. They're so cool it makes you WANT to flush your brake fluid!

[ska69]

I wish you to make your dream come true

so any idea if dorman 12706 for s13? or I guess it should be q45 specific?

looks like 12706 is M10-1.0 x 33mm and fits q45, whilst 12709 is M10-1.0 x 35mm

btw, I got rebuilt calipers, how do I tell if they have speed bleeders or not?

[float_6969]

It should all be the 12709, probably for all Nissan's.

The issue is that they measure the overall length, and when you compare the two, the lengths are correct. The difference is that in the Dorman part, the actual amount of the length that is threads, is far less than the Nissan part. So it ends up bottoming out on the hex head and not sealing at the inverted flare.

The chances of your rebuilt calipers having speed bleeders are slim to none.

[ska69]

thanks for the explanation, I'll go with the 12709's too. you're running q45's right?

[float_6969]

yea, q45 fronts, stock S14 rear

[float_6969]

Small update, no pics though. I built the new adapter bracket yesterday. This time I used 1/2" aluminum instead of 1/4" to space it further out from the firewall so the reservoir would sit straight. It worked perfectly, but the extra 1/4" made the pedal clevis too short. I made another one that was longer, but it needs a 5/16"-24 nut welded onto it and it was too late to get one last night. Pics of finished product and impressions of new brake master position coming on Wednesday.

[float_6969]

It's done!



So the finished product used the stock brake pin location on the pedal. If I were going to do it again, I would move the pivot point up about 1/4" and build the bracket to suit, but since I had already drilled holes, I couldn't do that, plus I didn't want to build ANOTHER bracket. I did stick with the 13/16" master cylinder. Overall I'm pretty happy with the results now. The pedal is still a big harder to push then I'd like, but it's manageable. More importantly, the height of the pedal is about perfect now for my "modified heel/toe" downshift now. I rode around while my wife drove for a while tonight, and she feels like the pedal is too hard, but she's also very petite.

After all of this, I'm glad I did this myself, but I think the Chase Bays kit would have given me similar results. It would make the pedal even harder than it is now, but I think the Chase Bays kit was geared more towards Z32 brakes, which would work well with the 7/8" master that comes with the chase bays kit.

[Razi]

Is there very little pedal travel now?
I'm tempted to do this now haha.

[float_6969]

Compared to a 15/16" master on stock pedal, there is more travel, but less than when I had the 6.5:1 pedal ratio. What I was aiming for was for the pedal to be about even with the gas pedal when the pedal was firmly depressed. This is almost exactly what I got. I was able to easily blip the throttle on decel and downshift for the first time since I started everything with the turbo kit. I'm happy with it and would reccomend it. I will say that if you want the pedal travel to be less, and are OK with a bit more pedal effort, the Chase Bay's kit will give you this exactly. Also remember this is only applicable if you've got Q45 fronts and S14 rears. Any changes from that will effect the pedal travel and pedal effort.

[IanS]

So how much did the master cylinder and bias adjuster end up costing you? I really want bias adjustment, but have been putting it off because ther cost is rather high for somehting like the chase bays kit.

[float_6969]

I got them straight from willwood as their prices on their webite, but IIRC, I paid $130 for the combination master kit and proportioning valve. The adapter plate cost me about $20 in fasteners (I used all stainless steel) and I got the aluminum plate for free.

I drove the car around a bit before I took it apart the second time and ended up turning the proportioning valve off completely (meaning full pressure is going to the rears) and it has improved the feel of the brakes dramatically. Compared to full pressure reduction to the rear. As a test. I pulled the ABS fuse to see if the rears would even lock up and they won't. The fronts always lock up first. From what I understand, this indicates that the stock rear brakes may not be big enough to balance out the front. What I've read is that to adjust the bias, the proportioning valve should be turned "down" (full pressure to rear brakes) and then try to lock up the brakes. If the hardware is correct, the rears should lock first. You then begin to turn the proportioning valve "up" (reducing pressure to rear) until the rears lock just after the fronts.

Because of this, I already have made plans to try the Z31 rear brake caliper bracket with the Altima rotors to see if that will increase rear braking enough that I can actually balance the system. The way things are right now, I don't even see a need for a proportioning valve as the more pressure I sent to the rear, the better the car behaved.

[float_6969]

I just wanted to update this with some more recent driving impressions.

First thing is that I'm not happy with the pedal position and pressure anymore. The pedal is VERY firm. Like your leg gets tired driving in town firm. And the point where it engages is too high to heel-toe comfortably. I'm considering dropping down another size in the MC. If that doesn't work, I'm going to have to come up with another brake pedal and re-drill it, as my current one has too many holes in it now to make any new holes.

Also, I was talking about brake bias. I have been still trying to get this issue sorted out. Currently I'm running Q45 fronts and S14 rears w/Z31 (84-86) caliper brackets and Altima rotors. In another thread, I've figured out the Altima rotors are too small in diameter and I'm trying to sort out a solution. The issue is a lack of braking force in the rear.

The car stops fine and is safe to drive, I just think I could be better.