Bigger rotors on stock GPX calipers?

wildfaye · Post by **wildfaye** » Tue May 25, 2004 2:03 am

Has anyone tried this? Any fitment problems? Usage problems?

Any feedback appreciated!

Cheers!

GPXXX · Post by **GPXXX** » Tue May 25, 2004 11:06 am

I believe SilentBob has one fitted just recently...

UAS is also developing a stage 1 brake upgrade kit as well - stay tuned for details.

SilentBob · Post by **SilentBob** » Tue May 25, 2004 12:49 pm

nah i replaced my front rotors, but just with standard sizing...

to replace with bigger some adjustment will need to be made to the mounting of the calipers(due to the limited clearance between them and rotors)..

steve mentioned that UAS were 'developing' a bracked to allow the fitment of a larger rotor to the fronts, but would more than likely also require having 17" wheels for the clearance side of things...

Im sure he'll post details at some stage
SilentBob

wildfaye · Post by **wildfaye** » Tue May 25, 2004 1:15 pm

Hi guys, I did a check on the DBA website and here are the results:

http://www.dba.com.au/dba_catalogue_200 ... ubishi.pdf

Under FTO, the fronts are 425.
Take a close look at the specs of the front discs.
Than look at 417 under Evo IV.

These fits 16" and the specific dimensions are all pretty similar, with the 417 being almost 20mm larger.

FTO DBA 425: 276x45x24x22.4x69x5
EVO IV DBA 417: 294x46x24x22.4x69x5
--------------------------------------

Now for the rears.
FTO DBA 547:260x41x10x8.4x90x5

I can't find a larger similar spec in the Mitsubishi range. But found these others instead:

Honda S2000 DBA 483: 282x40x12x10x64x5
Mazda 6 DBA2951:280x40x10x8x72x5
(both are pcd of 114.3x5 from memory and should fit perfectly by boring out the centre bore of the discs.)

http://www.dba.com.au/dba_catalogue_200 ... /Honda.pdf
http://www.dba.com.au/dba_catalogue_200 ... /Mazda.pdf
--------------------------------------

Any comments on these?

SilentBob · Post by **SilentBob** » Tue May 25, 2004 2:00 pm

im pretty sure those were the rotors that they were looking at using....

just need to work out how to shift the caliper back 1cm or so due to the larger rotors
wouldnt be hard and i guess thats why they developing it...

wouldnt imagine a HUGE improvment from this, but the cooling side of things would assist in reducing brake fade/repeated braking

Post by **smorison** » Tue May 25, 2004 3:12 pm

one of the front struts is out of my car at the moment, we are building two brake upgrade kits...

Stage ONE:
* 330mm rotors
* Stock callipers
* mounting bracket for stock callipers

Stage TWO:
* 330mm rotors
* Brembo Callipers (about $700.00 extra for these)
* mounting bracket for new callipers

The Brembo's we are looking at come of a lotus elise from memory and are fantastic - i've held them... mmmmmmm brembo's.....

i will have more information by the end of the week...

btw current UniqueFTO projects are:
* Adjust exhaust CAM gears
* electronic Waterpump
* Tranmission Radiator[/b]

TheSentry · Post by **TheSentry** » Tue May 25, 2004 3:28 pm

Steve, how many pistons do the Brembos have?

SilentBob · Post by **SilentBob** » Tue May 25, 2004 3:35 pm

smorison wrote:Tranmission Radiator

now i wonder when the inspiration for this arose.... ?

SilentBob

wildfaye · Post by **wildfaye** » Tue May 25, 2004 4:23 pm

330mm on stock GPX calipers? Fits 16" wheels?

Any upsizing for the rears?

Have you taken a look at the DBA parts i listed above? do u reckon its a direct bolt on w/o mods?

wildfaye · Post by **wildfaye** » Tue May 25, 2004 4:27 pm

Transmission radiator?

Cooler u mean? I have one installed, I am not sure of the temps after the install, but the gearbox is def smoother.
I have an engine oil cooler installed as well.

Those 'Cusco' front struts with brake cylinder stopper: are they avail yet?

I have a original cusco strut and was wondering if i can get the mounting with the cylinder stopper and bolt on the existing strut?

SilentBob · Post by **SilentBob** » Tue May 25, 2004 4:39 pm

if the 'brake master stopper' is the same as currently on steve's car it doesnt attach to the strut bar, but the wall in the engine bay next to the brake cylinder
though, you may have to check your car isnt 'different' like mine, because when we fitted the strut brace my brake cylinder is further towards the front of the car due to a larger brake booster, hence a 'stopper' like this would not be 'doable'

SilentBob

Post by **smorison** » Tue May 25, 2004 5:22 pm

SilentBob wrote:if the 'brake master stopper' is the same as currently on steve's car it doesnt attach to the strut bar, but the wall in the engine bay next to the brake cylinder
though, you may have to check your car isnt 'different' like mine, because when we fitted the strut brace my brake cylinder is further towards the front of the car due to a larger brake booster, hence a 'stopper' like this would not be 'doable'

SilentBob

ok

transmission raditor = overheating on the track need to cool it down

brembos are larger twin pots

adam: we should test fit one to yours it is adjustable so it should fit.

the upgrade kits are for 17" wheels or larger....

wildfaye · Post by **wildfaye** » Tue May 25, 2004 5:23 pm

errm...bob...i am not sure if we understand each other correctly...

so...lets try again...

the brake booster is the one on the fire wall.
the brake cylinder extends towards the front of the booster.
the brake cylinder stopper is a bracket that prevents the cylinder from moving hence reducing 'sponginess': this is supposed to be an adjustible bracket rite?

the project being done up is supposed to have:
the strut bar mounting(brake cylinder side) which will extend downwards to the side of the cylinder(next to the wall) will incorporate the the bracket to hold the brake cylinder hence prevent movement.
am i rite?

since the mounting + bracket is supposed to be made from a cusco bar, would it be possible to buy the 'new' mounting that incorporates the brake cylinder stopper? and bolt up the cusco bar i already have?

smorison: any pics on this would greatly help...thanks!

Post by **smorison** » Tue May 25, 2004 5:35 pm

ooops i knew i forgot to update something...

the master cylinder support we decided not to incorporate as it was too hard to engineer it to be strong enough and easy to remove (i.e. to do engine work)...

i'll try and update all this tonight...

wildfaye · Post by **wildfaye** » Wed May 26, 2004 1:42 pm

Ohhh jezzz...and i tot i could get some custom made brake stopper...
hmm...

Post by **smorison** » Wed May 26, 2004 1:55 pm

wildfaye wrote:Ohhh jezzz...and i tot i could get some custom made brake stopper...
hmm...

???

fto617 · Post by **fto617** » Wed May 26, 2004 2:31 pm

hey stephen !
what actually does brake upgrades do???
coz i reckon the stock brakes are not good enough man !!!
oh and when is the cf bonner group buy goin ahead???
i'm in urgent situation !
crashed my car yesterday
killed the front bumper brackets
and the bonnet jsut bent !
damn man i hate driving in rain >.<
lucky it skidded when it was goin at only 20km/h
not bad damage just mispositioned bumper

wildfaye · Post by **wildfaye** » Wed May 26, 2004 2:37 pm

smorison wrote:
wildfaye wrote:Ohhh jezzz...and i tot i could get some custom made brake stopper...
hmm...

???

What i meant was:

I tot i was able to buy the left 'cusco' modded strut bar holder that incorporates the adjustable brake cylinder.

now that the project has been dropped...pop goes my bubble...

hmm...btw, u peeps considering making a fto specific brake cylinder stopper?

TheSentry · Post by **TheSentry** » Wed May 26, 2004 2:49 pm

fto617 wrote:hey stephen !
what actually does brake upgrades do???
coz i reckon the stock brakes are not good enough man !!!
oh and when is the cf bonner group buy goin ahead???
i'm in urgent situation !
crashed my car yesterday
killed the front bumper brackets
and the bonnet jsut bent !
damn man i hate driving in rain >.<
lucky it skidded when it was goin at only 20km/h
not bad damage just mispositioned bumper

Bit confused here but are u saying your brakes are to blame for your accident?

Post by **smorison** » Wed May 26, 2004 3:20 pm

fto617 wrote: what actually does brake upgrades do???
coz i reckon the stock brakes are not good enough man !!!

I currently use the stock MIVEC (GR callipers are smaller) with racebrake pads and have no problems stopping even on the race track... The Callipers are the same as those used in EVO's (upto evo4 or 5) so they are definately upto the job... i have ZERO brake fad even after 15+ minutes on the track....

as much as i'm probably talking someone out of our brake upgrade kit (buying it for possibly the wrong reasons) i would say upgrade your pads to a better quality pad and check your rubber it's possibly not upto the job... most importantly always be alert when driving and ensure you keep a safe distance between yourself and other cars especially in the wet.

things to consider:

brake fluid - should be atleast dot 5.1
brake pads - don't skimp on these!!!
rotors - are they screwed do they need machining?
tyres - are they worn out??? are they a cheap tyre?

so i guess your wondering why we are doing a brake upgrade kit now... well i'm planning to (and i'm sure others will as well) run semi slick / slick tyres on the tracks from now on... as there is more rubber on the road we need a better braking system that won't overheat with trying to slow down the car with the added traction...