Designing a GH sigma big brake kit?

[Capo]

Hi all

I'm in the process of going through A big brake upgrade, now I have done a lot of research and seen my lack of options.
The available options are not what I want/too pricey for what you actually get. (nsx hybrid kit thing and hopper stoppers kits and simple vented slotted discs etc) as I say this money isn't an issue but I personally find it fun in trying to find a different solution for everyone and me, because last week I was set on forking out for a hopper stoppers front and rear brake kits and I still might but I thought how hard could it be to design my own kit really?

So my first question is if I design a "engineered accepted kit" do you think I should keep everyone else in mind when I'm designing it or just go for a one off "keep myself happy kit"? Because I could develop a kit so people could buy off me or something.
The difference between the both would leave me down separate paths. And I'm honestly happy doing either or.

I've read up on engineering regs. And from what I've read the caliper bracket (which I guess is my main obstacle in the whole kit) must use the original hub caliper bolt locations and correct bolts, and must not come into contact with anything no grinding welding bending etc etc. So with this stated once I find the right thickness and type of metal to use for the bracket which is my biggest issue but what I've seen on the net doesn't have to be anything special I'll just have to get clarification that's all.
So still on the bracket issue I can mount the caliper top front back anywhere I always like front no reason why I just do, any opinions? I was going to aviod top mount incase the caliper gets too close to the strut.

As for calipers I wanted to go 4pot front 2pot rears especially with the power I want to throw in my car.
So next question, I wanted to avoid say brembo or wilwood type kits too expensive, I want to use a set up from a standard production car eg I'm spit balling here with the examples; keeping it Mitsubishi, gto, lancer, evo, magna etc or should I go some other family of car like Toyota supra soarer or nissan skyline - I really would like some feed back here because I have sooo many options to rule out. So advice will be really helpful.

Rear drum brakes will be obviously removed and replaced with the convetional modern day rear disc brake and handbrake setup where the handbrake is incorporated in the caliper (for those who are unfamiliar). I wanted to try and keep it matching with the same car as the front brakes to keep it easier to hunt for when making it a" kit" but really doesn't matter where get it from I guess.

I know Ive blabbed on long enough so quickly disc rotors will be last on the menu as obviously we need to know what caliper I'm going with. I was naturally going to include pads and new lines, but with a good upgrade we need a new booster and lines with the booster I was going to use the car the we get the caliper and what not from.



If I missed anything let me know and please throw out opinions out too. Sorry for the lengthy post.

[cheaterparts]

Hi all

I'm in the process of going through A big brake upgrade, now I have done a lot of research and seen my lack of options.
The available options are not what I want/too pricey for what you actually get.

So my first question is if I design a "engineered accepted kit" do you think I should keep everyone else in mind when I'm designing it or just go for a one off "keep myself happy kit"? Because I could develop a kit so people could buy off me or something.
The difference between the both would leave me down separate paths. And I'm honestly happy doing either or.

As for calipers I wanted to go 4pot front 2pot rears especially with the power I want to throw in my car.
So next question, I wanted to avoid say brembo or wilwood type kits too expensive, I want to use a set up from a standard production car eg I'm spit balling here with the examples; keeping it Mitsubishi, gto, lancer, evo, magna etc or should I go some other family of car like Toyota supra soarer or nissan skyline - I really would like some feed back here because I have sooo many options to rule out. So advice will be really helpful.

I know Ive blabbed on long enough so quickly disc rotors will be last on the menu as obviously we need to know what caliper I'm going with. I was naturally going to include pads and new lines, but with a good upgrade we need a new booster and lines with the booster I was going to use the car the we get the caliper and what not from.

my sigma has prob done more high speed hard braking than most on here and I had thought of upgrading my brakes as well

for those that know my car its a little lighter than some road cars but still weighs in at 990 Kg + driver
I use basic starion brakes and they have held up pretty well - unlike a road car the brakes get serviced a lot more offen
(after every event) the biggest problem is pads
there are no off the shelf items that cut it here in Oz , so I now have Potterfeild carbon kevlar pads from the states
great for both braking power and handling the heat with out fade

anyway I had planed to upsize the brakes and was looking at using holden dunnydore discs - these can be got undrilled and fairly cheap - it just takes a small amount of time to drill them to suit the 4 1/2" PCD (114.3 mm ) 4 stud patern
I dont need a hand brake being a circuit car so I've planed to use the same caliper set up as a commodore cup car
which is basicly fitting an early model front caliper on the rear with the smaller commodore early front disc ( Pn - RDO 20 )on the rear
and for the front a later larger holden disc ( Pn - RDO19) with twin piston sliding calipers

I know none of this gear looks fancy but they use them on C/cup cars that weigh 200 - 300 Kg more than the sigma,
are braking from higher speeds and there are pads avalable

this may no help you with your upgrade but Its what I had planned

[BIG26L]

What are using the car for???????? There should be plenty of options here.

From memory early commodore discs and caliper bolt up? Don't quote me on this, I havent been down this route the conversion myself.

We have used GTR disc's and calipers on the front of my tarmac rally car (LC coupe) and S3 RX7 disc's and 2 spot GTR rear calipers. I have had custom one piece T6061 calipers mounts fabricated for the Sigma strut bodies on the front and Mazda 929 diff in the rear and they just, and I mean just fit inside 15 inch wheels.

We are using a hydraulic handbrake, and a Wilwood pedal box so you would still have to fabricate a handbrake assembly and sort a booster to suit.

The GTR 4 spot caliper is the same as S6 RX7, WRX STI and EVO so there will be plenty of pad compounds available for them.

On the rear, S3 RX7 uses the 4x114.3 stud pattern, so it doesn't take much to make them fit. S3 bluebird and Pintara is another option if you looking for a solid disc rear brake assembly to use.

Have you tried Hopper Stopper? they do a kit for the front of a sigma with the choice of 4 or 5 stud hubs and they are ADR approved.

Most of the mazda boys use S4/5/6 or 7 brakes on the early mazda's (we've used this set-up on a number of cars and they engineer has no drama's with it) and the rear calipers have cable operated hand brakes, so custom cables can be made to suit.

Hoonboy had a set up for sale a while ago using NSX discs and 4spots caliper of what type I can't remember.

Hope this helps a bit more.

[gaz914]

Hi all

I'm in the process of going through A big brake upgrade, now I have done a lot of research and seen my lack of options.
The available options are not what I want/too pricey for what you actually get. (nsx hybrid kit thing and hopper stoppers kits and simple vented slotted discs etc) as I say this money isn't an issue but I personally find it fun in trying to find a different solution for everyone and me, because last week I was set on forking out for a hopper stoppers front and rear brake kits and I still might but I thought how hard could it be to design my own kit really?

It's simple and there is a huge market for them, that's why there are 100s of kits out there for sigmas...wait, what??

Just a few sums for new parts:
2 x DBA discs $300
2 x PBR calipers $300
2 x brake lines - custom $100
1 x set (decent) brake pads $120
1 x larger Master cylinder $250

Around $1100 (Yes you can look around and find cheaper bits or used), then there is cost of making brackets, machining the discs to fit, bolts, etc
Hoppers at $1600 sounds reasonable.

Not many businesses are going to sell second hand bits for a brake conversion, so no point arguing about 2nd hand Nissan/Hilux/Subaru calipers.
Same with discs/pads, cheaper isn't better for a "performance brake upgrade".

Then think about the effort in making it fit, clearances, wheel fitment, etc. I know your time isn't valuable

But go ahead and let us know how you go.

cheers
Gaz

[A112H]

I think a lot of people get hung up on having "big" brakes. Both the Lancer and my hardtop are under 1000kg so really don't need massive brakes and for a road car they are a waste of money, IMHO.
Mine have been upgraded to GH Sigma and have slotted DBA rotors with stock rear drums (will be disc's when I get the EX diff sorted) I have had no issue with these brakes in road use and think they would be fine for your Lancer.
My 35mm spacers do just about make my rotors sit outside of the rim so get awesome airflow, this would help keep them cool when being used hard but in general road use with the odd thrash threw the hills this set up is perfectly fine.

[Capo]

Good to hear some replies,

Thanks Gaz your right in theory which is why I almost bought it and that's why I'm comparing my "potential kit" to the hoppers kit because it's the bench mark. The major difference will be using used calipers as to new in hoppers and also 4pots to twin pots respectively.
There is absolutely nothing wrong with the hopper stoppers kits, I want to see if I can get better for less and it's twin pot kit. I was quoted $2380 for everything from hoppers. So I understand the resentment I suppose but its always nice to have alternatives and the power I'm throwing  at the wheels the twin pots won't be even close to being enough stopping power.
With the power I'm throwing in it aprox 300-350kw at it I want it to stop, so 4pots are on the menu and the research that I did today, I've found I can get evo6 calipers for $400 (fronts) and GTO calipers for $250 (fronts). Supra calipers for $800 and celsior/ls400 for $600 also fronts.

Get the brackets made up isn't an expensive exercise I know a couple of place that can help bolts arnt a great expense it's calipers, discs and pads and the master cylinder.

So I'm still into the research phase but the rx7 option is interesting, how much power these cars have and do you get much brake fade at all with your set up at all?

Your definitely right about falcon and commodore kit being more available and an avenue I'm going to look into.

Im planning on using the car for a lot of things but setting it up for track.

[cheaterparts]

With the power I'm throwing in it aprox 300-350kw at it I want it to stop, so 4pots are on the menu and the research that I did today, I've found I can get evo6 calipers for $400 (fronts) and GTO calipers for $250 (fronts). Supra calipers for $800 and celsior/ls400 for $600 also fronts.

Get the brackets made up isn't an expensive exercise I know a couple of place that can help bolts arnt a great expense it's calipers, discs and pads and the master cylinder.

Im planning on using the car for a lot of things but setting it up for track.

I'm more interested in what you are doing to pull the 400 - 470 hp , my thoughts with the money you are spending on the engine , the brakes sound cheap

and what track work are you going to do

[BIG26L]

Next question is what size wheels are you going to use?????

The bigger and wider the disc the better. I'm limited to 15" wheels for my class and am using approx 290mm rotors.

Most of the early model IPRA cars are using 15" wheels due to being limited to 50 series tyres. Most of the them fit 300 to 310mm discs inside them, again just!

We just installed 355mm disc hats and 6 pistons calipers on my brothers Golf Gtd (yes diesel) and it needed 18" wheels to clear them. But what a massive difference they make on a 1400kg car.

If you do your sums right, you won't need to change the master cylinder size either.

HSV/Harrop calipers and disc's might be another good option to look at. You can buy Commodore redline Brembo's and disc's on ebay for next to nothing.

[cheaterparts]

Next question is what size wheels are you going to use?????

The bigger and wider the disc the better. I'm limited to 15" wheels for my class and am using approx 290mm rotors.

Most of the early model IPRA cars are using 15" wheels due to being limited to 50 series tyres. Most of the them fit 300 to 310mm discs inside them, again just!

it is the biggest dia wheel thats legal for IPRA 4 cylinder cars made before 1986 - that fine you can get plenty of brake under them

I still have 13 " wheels over starion brakes atm but with the newer tyre rules going up to a 15 x 7 rim is the go
and the AO50 it seams dont go off as quick as the AO48s

[BIG26L]

Correct!

Once the current set of 48's are dead on my supersprint toy, (Mazda 323, 13B PP, Volvo brakes, etc......) I'm going to try a set. I'm only hearing good reports so far........

Was going to go back to 13" wheels and keep the 4.4 gears, but can only get 175's in a 13 now.........So the 15's stay and time to purchase some 5.1 gears.

[Capo]

Wheels I'm planing on using are 15x8 which I'm getting conformation on internal measurements of the rims from rota.
But if the 15s don't fit over the brakes then I've got the option to go 16s as well which really doesn't phase me, I suppose it depends on the brakes. Which thinking about it there's like $80 difference between 15s and 16s.

As for the motor and g/box well it's a secret and I have it already in my possession and will be working on it soon and will reveal it when I start my project thread but I will say it's not a 4cyclinder, but my first thing on my list is brakes so I can decide on wheel sizes which will then let me decide on a diff and widths

Yeah will definitely look into commodore brakes sounds promising, I need to get info on physical size of all these calipers because it really does matter for example the Lexus ls400 caliper are massive in size as are the supra so I'm assuming so will be the falcon and commodores because the pot sizes vary from make to make.

As for the track I'm not sure, I've never been apart of that scene all I know is I want to get out there but I like the idea of time attack. But I think I'll build the car first.

[amgis_obrut]

a 290-300mm vented disc and a 2 piston faclcodore caliper will be more than enough to stop a sigma with 350wkw

My GH has 290mm vented falcon discs up front with a WB holden caliper (will change to a VT commo caliper later) and EF falcon discs and calipers on the rear, it weighs a fair bit more that other GH's and stops well

I have 225 tyres all round, i think i'd run out of traction before my brakes ever became an issue

My Soarer has its std brakes and stops well (it could do better) its 1600+ kg and is making over 300wkw its only a 296mm front disc and a two piston caliper, rears are 307mm and single piston

[Capo]

Did you take that car to the track often?

Because in my old supra that had 240kw and the standard twin piston calipers with ebc redstuff pads and slotted disc braided lines the car weighed 1580kg and I took it too a track day and got massive brake fade and had absolutely no confidence in jumping on the brakes after 3 laps it just couldn't pull the car up to my liking, That's why I've decided I want the 4pistons.

Been doing some research and it seems like the xr6 and commodore ss calipers are a little pricey in comparison to the rx7, evo6, wrx 06, I've ruled out the supra and ls400 calipers too pricey. That's where I am at.

[Superscan811]

I was looking into a decent brake upgrade solution a while ago.

I like Wilwood calipers and have bought a few in preparation for my track car build.

The caliper on the far right is the standard Starion, the rest are of course Wilwoods.



The top caliper should be road legal because it has dust boots but a while ago I was able to find some silicon "boots" that would fit the other calipers that didn't have dust boots.

They would all have to be engineered to be driven on the street but for track use, they would be fine as is.

The 300mm rotors I found that would be the easiest to fit are off a 2004 Ford Focus (from memory) and if you are using a scorpion diff (unlikely with 300+kw) there is a Saab 300mm front rotor that is an almost perfect fit.

Unless you are going to buy an "off the shelf" kit, do some more research especially with the fluid displacement required to properly actuate the brake calipers. It aint rocket science but it does require a good understanding of area, volume and mechanical advantage. A good YR12 High School student doing Physics should have no trouble working it all out.

Cheers.

[amgis_obrut]

VT SS calipers are like $150 pair

[Capo]

Yeah for the standard 2 piston calipers but for the aftermarket vt vy ss 4piston calipers there $800 sorry I didn't make myself clear earlier itsthe same for xr6 aswell

[amgis_obrut]

first thing you'll need to do (before even looking at calipers) is figure out what disc you're going to use and how thick it will be, as you dont want pads/pistons falling out when the pads get thin, or the disc binding when hot because its to thick for the caliper

then it will be how to mount the disc, use the sigma hub or something else, I use XA falcon hubs that set the wheel mounting flange back about 10mm, I run a 16x8 wheel with a +10 offset and with a 225 tyre just fits under the guard and clears the strut be 3mm, The disc clears the lower control arm by about 2mm

I have tried to fit a 4 piston caliper but it hits the rear of my simmoms wheels, I could go for more offset or a different hub but the tyres will stick out past the guard, i could fit narrower wheel/tyre but that reduces my stopping power and makes a 4 piston caliper pointless, if i move the disc back it hits the LCA or i could hang the tyres out and fit flares but that looks like poo

theres not a lot of room to play with on a GH


BTW a big brake kit to suit a TE TF cortina is a bolt on for the GH sigma

[Scorpma82]

Trust me.....for a street car....you dont want massive brakes.........

So what happens....you put these huge brakes on your car...so now your car can outbrake anything on the road.....that's including the goon with no springs the rear....20" wheels on the front, stockies in the rear........theres only one outcome.......

I had massive 6-piston calipers front and 4-piston caliper seyup on my car.......and found out that i was never actually using them to their full potential in an emergency stop because i was delibeerately 'overshooting' my stopping point so i wasn't rammed by the car behind.....i was only braking as hard as the car behind me.......don't get me wrong....they were great to have....but just be weary about the extra braking power you will end up with if you were to upgrade to massive brakes

[turbosigma]

Will agree with that. Not thinking anything of it - stopping at a few red lights - here a few lockups behind me.
The other thing that gets you. Being a smallish/light car and getting them up to temp and keeping them there. Big disks get cold after freeway drive.

That said - Would only remove my 4 pots if I was upgrading. And there over kill as is.

[Scorpma82]

yeah i'm looking to do a brake upgrade on my car still (after all, i did work at PBR)....just not gonna go nuts.....although i'd love to lol

[Scorpma82]

yeah i saw this the other day.......great article.....but i wouldn't go to the expense of putting Wilwood calipers on a regular street car......quite an overkill.....mainly in the cost dept....still...if you've got racing in mind....a good option

[dvsfin]

Wilwood aren't that expensive