My Brake Swap (will clean up soon) by cuttyman9

12 minute read

My Brake Swap (will clean up soon) 

Compliments of cuttyman9 @ http://5thgencelica.com

1-7-2015

Brake swap
Hi,
   I'm posting this to show my progress of my brake swap on my 5th generation celica.

The car:
1992 celica GT hatchback

The parts involved:
-porsche brembo brake calipers, 4 pot (mine are from a 986 boxster S) x2
-custom made 6061 brackets x2
-12.9 grade m12x1.75 allen headed bolts x4
-10.9 grade m12x1.75 hex head bolts x4
-stainless braided lines 10mm ends(one banjo, one standard) x2
-2004 STi 12.8" rotor 5x100 pattern x2
-hub spacers 56.1 to 54.1


As of now the brackets are a little too tall so they aren't fitting under my 17" wheels
after milling them a bit I will post final measurements.
once get to installing I plan to weight the different components to see the differences.
I expect the caliper to be marginally lighter and the rotor a bit heavier.

the potential improvements are:
-3 more pistons worth of clamping force
-legendary brembo performance
-2 inch larger diameter rotor
-twice the initial thickness of the rotor
-better brake lines for strong pedal feel
-aesthetically pleasing



thanks for viewing.
let me know if you have questions

dammit, this thing is being a pain, if I preview the thing I basically lose what I wrote because I cant scroll down far enough.
frustrating....

anyways
pics work through photobucket.

^ spindle alone

^ spindle with the first bracket design. This bracket doesn't work with boxster S(986) calipers(too short) got the solidworks design from someone on alltrac.net

^ this is a mock up with the first bracket, a shit-ton of washers and super long bolt. Would work with a 911 caliper if anyones interested in these brackets let me know.

^ caliper with the factory finish removed, factory annodizing can be seen, don't remove it. Also make sure to get front caliper, rears look identical but have smaller pistons in them.

^ True Brembos- proof

more pics

^ brackets with bolts, these are the first run for 911 calipers, also had to modify them slightly so they would clear the areas on the spindle. They were supposed to bolt on without an issue but apparently the design I had been given was entirely right. bolts are 12.9 rated metric on the caliper to bracket portion 2.75 inches underhead length, 10.9 rated on the caliper to spindle part 1.5 inch underhead length. m12x1.75 thread pitch for all bolts
The top ones from the caliper to the bracket are allen headed.

^ repainted caliper, red and green isn't the color combo I want. Used high temp engine paint(daytona yellow) this will be followed with clear header paint over the stickers once everything is said and done sourced from ebay.

^ another shot of the caliper repainted, caliper part numbers; 986.351.422 and 986.351.421

^ vinyl brembo stickers

^ caliper with the brembo vinyl sourced from ebay

^ bracket revision one, this is a slight bit too large working on that aspect soon. Revised bolt holes to spindle so no modifications were needed to bolt it up.

^ noticeable difference in the two brackets when bolt holes are lined up

more pics

^ rotor thickness difference

^ rotor installed, note that the factory dust shield interferes so it should be removed

^ thanks to a friend who already swapped this setup on, this is the clearance when all is said and done with a set of 17x9 +35 drag dr31's

^ difference in diameter, solid 2 inch gain for a much better cooling capacity.

^ this is a picture of the difference between the 986 and 996/997/998 caliper, the extra material on the caliper makes all the difference.


another thing to note is the pegs that hold the pads up have to be trimmed down, they are intended for a smaller width rotor.

more updates: test fitted new brackets with spacers to find the amount needing to be shaved from the brackets.

have some more pics for the package. About a quarter inch short of fitting under the wheels.

^differences in the stock vs custom bits

^spacer for the disc

^ the cheap rotors I got off ebay (100 a pair)

^more with the caliper bolted up

^top shot of the caliper over the rotor

^backside of the bracket and caliper

^opening for the pads



alright so for those of you watching this thread I've learned a few things.

-not all brembo calipers are equal
-the part number is the way to determine what the caliper is from
-stoptech calipers(ST40) are the same radial bolt pattern as 996,997,998 and 986 Porsche calipers
-993 turbo Porsche calipers are almost the same as the stoptech St40's
-base boxster calipers do not work with STi rotors


so this being said my old brembos are out the door (useless unless I can make them work on the rear, but thats for another day) so I almost scrapped the big brake idea all together but I did find the 3000gt vr4 calipers so I decided to determine what it takes to mount them. The brackets i saw being used were factory 92-93 caliper brackets with the front portion hacked off. It is then a matter of drilling and tapping the appropriate holes for the VR4 calipers. The other roadblock I came to was that the bracket with the STi rotor would not fit on the outward side and the bracket hit the spindle on the opposite side of the spindle ears.
that is about where I stopped.

Then I found a pair of stoptechs in reasonable shape for a much better price than some 911/boxster S calipers, figured I could flip em if any problems arose. turns out that stoptech was smart and used some production style parts and tweaked them to work in the aftermarket. the stoptech ST40's I bought came from an evo 8 which when purchased as a kit come with 332mmx32mm rotors, this means that they are pretty damn close to the Sti's 226mmx30mm rotor. The caliper brackets line the calipers up with the rotor almost perfectly, they are a slight bit too far out radially as well as too far out toward the wheel. These calipers also use a relatively common pad: 993 turbo pad(911 turbo from 93-98)
I should have some revisions to my more recent bracket design finished in solidworks as a PDF file in case someone wants measurements.

next up to check was whether or not this setup would fit my wheels.
the results are that the subie rotor and stoptech caliper will fit 17's, but not all 17's are created equal.
to fit pretty much any 4 pot caliper its required to have a wheel with an outward set wheel spoke, unfortunately my volks (1997 volk racing AV3 17x8 +37 for reference) do not. On the other hand the Kosei K1 TS (17x9 +35) do fit the brakes (dunno yet about the car, I will be pushing the envelope on clearance with that wide of wheel on a narrow body celica) I believe my enkei's (17x8 RPF1 +45) will clear as they did with the brembos but I'll make sure to check before I sell them.

so after all is said and done and more money is spent in research and development lol I'll eventually get this all straightened out.

As a side note, I may finish the VR4 setup just to show how to do it and possibly sell what I put together as the meat and veg of the kit for someone else with a celica, let me know if this is of interest to you.

the summary of what I'm going with right now so far includes:
-stoptech ST40 calipers(evo
-stainless brake lines (included with the evo 8 calipers)
-993/stop tech pads
-STi Rotors
-center trim rings(54.1 to 56.1)                                     Note: until I switch to 5x114.3 then I'll modify the rotors to fit 60.1
-custom 6061-T6 aluminum brackets                              Note: designed for a porsche caliper
-same bolts as first post
-factory spindle with removed dust cover

So sometimes I feel like somewhat of a genius in my own mind. I was searching for rotors with a 5x114.3 pattern that might pick up some of the slack for the caliper( I need the caliper to be inboard .069" and downward toward the center of the spindle by .345") and in that search I realized IS350's come with big 4 pot calipers and it turns out their rotors are larger diameter than the STi's by 8mm and are moved outward 1.9mm which is almost exactly right for the setup.
once I get some cash I should be ordering a pair and also pressing the new hubs in so I can get to testing the layout.

The other advantage with the is350 rotors is that the hub center is 60.1 on the rotors and 60.1 on my rav4 hubs (part of my 5x114.3 swap its crazy how many wheel choices open up with just this one swap)

So the new setup will be:
-IS350 front rotors (334mmx30mm)
-stoptech calipers, ST-40's (setup for 332mmx32mm)
-993 porsche pads (look for D609 pads, they are setup for a porsche but are the same fitment for the ST-40's)
-custom brackets, if needed I can provide the template to make them.
-braided brake lines 10mm on both ends; one standard, one banjo


so far if you ignore the idea that I had to test certain things and those would be involved in the cost, if you total what Im using here it is
-rotors $101 (ebay)    centric part number 120.44138 and 120.44137
-calipers and lines $230 (came with brackets too but for an evo)
-brackets $50+6 pack (chunk of billet 6061 + machinists fee's lol)
-bolts $30 (local hardware surplus)
-pads $45 (ebay IMC 520 06090 508 in the search should bring up)

So roughly $456 total if you were to find the calipers cheap.
once I sell off all the extra parts I should be at this total.

If you need any other info let me know, this is where I am at so far.


^Is350 rotors


^92-93 celica rotor


^92-06 Camry rotor (v6 only) for temporary use