View Single Post
Old 07-16-2008, 01:21 PM   #1
burntZ
Registered User
 
burntZ's Avatar
 
Join Date: Mar 2005
Location: ocala, florida
Posts: 132
iTrader: (0)
DIY: Making your own [budget] BBK

Having been autocrossing & then tracking the z for 3.5 years, 50K miles i needed to replace the stock rotors. I looked into upgrading to used 06+ or brembo calipers but wanted new parts. ArizonaZcar came closest to what i wanted to do but i wanted to keep the rear parking brake intact and also wanted a larger / thicker pad then they have with their rear caliper choice.
[if you're likely to lop off a thumb with a grinder then go order their kits, an excellent choice for 6 pot fronts!]


The assembled parts on installation day.


The Plan: after stealing many ideas from the 23+ page long DIY brake thread i decided to order a pile of parts and make my own 4 wheel BBK, went for budget on most choices [ie plain over slotted rotors, black over red calipers, rotor size/type] going for the most brake 'bang' for my buck. Also now after 500+ miles tested i feel okay posting what i did to guide you other adventurous folk.

The Disclaimer: They are brakes!, they are IMPORTANT!, don't do this if you aren't sure you're doing it right, test them in unoccupied spaces that will only inconvience the poor rescue team scooping up your battered remains...


The Parts: Total Price $$1350! (+s/h)

Front calipers: [summitracing]
WIL-120-7429 R(ight) & L(eft) which are Wilwood 4 pot forged billet superlites with the 1.75" pistons

went with these for the pad selection, .8" thick , had a pair of dynalites for the rears but after seeing the thin pads (still much bigger than stock rear pads, how nissan can put them on a 'sports' car?) that came with the dynalites i decided to go big and use the FBSuperlites on the rear also

*editorial gibberish - if you have brembos already then i don't think you'll gain anything by doing this, slightly bigger pads, cheaper cost for pads, go spend your $$ somewhere else, how 'bout coilovers?
if you simply must have 6 pot calipers, go for it, no their is no difference in braking ability over the 4 pot caliper on this rotor, the increased pots (6 or 8 etc) are for large rotors so that the aluminum hub can be larger so that the heavy braking surface is smaller at the edge of the rotor and the smaller multi pots can all fit
SO having a higher number of pots on a rotor that isn't optomized for it is just a $ waster
Rear calipers:[summitracing]
WIL-120-7477 R / L 4 pot forged billet superlites with the 1.38" pistons

front & rear SS lines: [hrpworld or summitracing]
wil-220-9196 & 9197 with proper connectors


brake pads: [summitracing]
2 sets of wil-150-8854 bp10 - good street pad, good to 1100 degrees!

*optional wil-150-5939k (polymatrix b) track only pads (good to 1300 degrees!) $120 bucks for excellent track pads!! will do a celebration dance every time i have to replace em, you spend so much more for regular BBK pads (god bless wilwood!)


front & rear rotors
i went with brembo sized plain rotors (1 piece) [zeckhausen racing], i use my old 17 stock rims for my track tires so had to fit under them
2 piece are better than 1 piece BUT for my use, non $$ winning track days, i feel that the brembo rotors are more than sufficent and much much cheaper than any 2 piece rotor choice out their

Front Rotor info new [old]
324mm x 30mm [296 x 24] ( 20.5# vs 16.5# )
(12.76" x 1.18") [11.65]
Front Pad - 11.5 sq in vs 11.3 / .8" thick vs .49" (13.96 brembo)


Rear Rotor info new [old]
322mm x 22mm [292 x 16] (18.5# vs 12#)
(12.68" x .866") [11.5]
Rear Pad - 11.5 sq in vs 6.18 stock / .8" thick vs .4 (7.97 brembo)

larger is better for braking torque but the real benefit is the higher heat asorbtion. ~ 25% in front and ~50%!! in back.


The Mounting brackets:

I started with the front brackets.



these are my first mockup attempts, i used the paper caliper while awaiting the UPS guy (had the rotor) cardboard mockup bracket, very quick to make for quick cutting but it didn't hold up in the testing phase... the middle one is the first 1/4 steel plate mockup, welded nuts to it as spacers (planned to drill the threads out) but when actual caliper arrived found my spacer calculations where off and ended up using some washers


several failed attempts.. mostly on 1/8" thick practice plate , the upper right is the plywood rear template and the lower right is the successful front template in 1/8" sheet



here are outlines of the final brackets just prior to installation

And here's the trick for DIY brackets

1) get some 1/4" plywood for your own mockups

2) print out my pics, noting that the paper is 4 squares to the inch [the heavy lines are 1" apart] adjust this until it prints true

3) cut out the paper brackets, tape the outline onto the ply, trace outline it

4) using .5mm pencil ( or equivalent, NOT a sharpie, something thin as accuracy is important, measure once cut twice etc etc...)
poke hole thru the lower left mounting hole (point a) (it's centered on the graph paper!)
measure exactly 100mm to the right hole, mark this point (b)
draw line from point a to b
measure up from both points (90 degree angles are important) 18*mm[*see below]
draw parallel line 18mm above line ab
cross measure upper left to bott R, Bott L to Upper R to ensure your rectangle is square (redo until it is, paper is much cheaper than steel)
measure in from left and right top 5.5mm, mark points c & d,
measure from c to d, it should be 89mm (100 - 5.5 - 5.5=89)
once you have all these points poke small holes through onto the ply
*i measured/ labeled the tracing wrong* see futher posts if you have parts in hand, will post correct measurements next week!! SORRY!
[18mm* note from above, i know, it's marked 19mm, my brake pad tops sit 1mm above my brake rotors and i plan to redo them using either 5/16 or 3/8 steel plate in the next month or so ( also powdercoat em and calipers), this will require some slight sanding to the car brake mount points, 19mm works just fine, split it at 18.5? try all three, ply is cheap!]


added a pic of how the front pad stands a little above the rotor at 19mm between the caliper bolt centerline and the mounting bolt CL

accurately start the holes with a small nail tap to dent the wood, drill thru with a small drill bit, drill the top holes to 7/16 and the bottom to 9/16 - i use a stepped drill bit

remove paper, jigsaw out the bracket

Testing your fancy new bracket...
bolt bracket to caliper, it goes to the inside, insert a brake pad to check clearance, always use a washer next to aluminum parts
put on new rotor use lugnuts (with a large holed washer) to keep it tight, square
bolt bracket & caliper to car mount, i started with 2 washers between bracket and the mount as spacers, tighten up fairly snug without crushing the plywood
check how the rotor is centered in the caliper, should be close, try 3 washers which is closer? (don't get too anal until your doing this with the actual metal bracket) rotate rotor, make vroom vroom and brake squealing noises...
check how top of rotor aligns with top of brake pads
check how caliper mount area fits against mounting hole area



added a pic of what i mean by caliper to mount area fitment, its a very close fit already sinking it down 1 mm will need some small adjustments (took this pic today while changing to the trackpads / track tires for sat (running around alot thur, fri so this was the only free time) - also you can see the 2 washers i used as spacers on the bottom mounting hole bolts (gold colored) to center the caliper

the caliper has a casting ridge along the bottom of the hole tabs which can be sanded off ?1/3 mm here, then mark contact areas and sand as needed for clearance, should be less than 1mm! if it's more than that recheck all your work to this point because mine wasn't ( i used a sanding pad on a 4.5 inch grinder, careful, aluminum gets removed much quicker than steel!)

once wooden mockup mounting bracket is tweaked to your acceptance redo the same measurements onto the steel plate, jigsaws work but a cutting wheel on a grinder is faster. cut it out outside the line and then sand down to the line and round the corners and edges to make it pretty,
EYE PROTECTION FOLKS!!!

for the holes in metal use a metal punch to center the starting holes, i wasted much time thinking i could hold a drill bit steady to start the hole but each hole would wander .5mm or so and screw the whole works up


bolts etc - use grade 8 on final assembly!!!
i bought a variety of cheap grade 5s 7/16 and 9/16 1.25 inch, 1.5 inch & pile of washers for mockup, make sure they dont hit the rotor! use an extra washer on the outside to pull the bolt away from rotor ( if needed)
i plan on welding the NUTS (not bolts, edit, duh) to my next brackets for ease of installation

i used the wilwood instruction torques 7/16 47ftlbs/ 9/16 95 ft lbs and loctite red

thats all for todays lesson, planning to do the rear writeup after sebring 7/19!


http://s334.photobucket.com/albums/m410/alfajimBBK/ <-- my bbk pic place

Last edited by burntZ; 07-27-2008 at 12:32 PM. Reason: [to add more pics & i suck at measuring]
burntZ is offline   Reply With Quote