FRONT VENTILATED DISK UPGRADE KIT

Ben Wight · backyard mechanic Joined: 04 Oct 2001 Posts: 946

I have some ventilated disk brake kits using 240mm diameter ventilated rotors. This kit is designed to replace your existing solid front rotors with ventilated ones, whilst retaining your factory twin piston calipers. This is a bolt on kit using brand new rotors, with all parts supplied.

In summary, the rotor is virtually the same diameter as the standard solid rotor, except it is ventilated, which means it is thicker than the standard rotor. The caliper mounts in the same location, using the exact same method as standard, except due to the increase in thickness of the rotor, the caliper needs spacer plates inside the unit to increase the passage that the rotor passes through.

The ventilated rotor allows the heat absorbed by the brake componentry during braking, to be dissipated at a higher rate. This lowers component temperature, and increases the assembly's resistance to brake fade.

This type of upgrade would be ideal for weekend club sprints, rallys, etc, or for when a brake upgrade is specified by an auto engineer if an engine is installed that is heavier or has more horsepower than the original.

Due to the use of the standard caliper, a change in brake bias is not an issue. Brake balance therefore remains as good as factory.

The installation is literaly a bolt in job. Remove the wheel bearing dust cover, undo the nut retaining wheel bearing, slide hub off, unbolt standard rotor, bolt on ventilated rotor, unbolt caliper, seperate two halves, install spacers, bolt everything back together and bleed brakes.

Kits consist of:

2 x 240mm diameter brand new ventilated disks - machined, drilled and tapped so bolts to standard gemini hub,
4 x laser cut caliper spacers - mount inside gemini caliper to allow fitment over ventilated disk, no modifications involved, simple bolt in procedure,
4 x genuine Holden rubber seals for spacers,
8 x longer high tensile (grade Cool

bolts for calipers to allow for spacer thickness
simple to follow fitting instructions are provided so anyone can fit this kit with basic tools.

Price is $280 per kit with brand new rotors.

As I know some people will ask, slotted rotors will be about $500 for a kit, and cross drilled and slotted will be around the $600-$650 mark. Obviously standard rotors are a lot cheaper.

If you want photos, or have any technical questions, let me know.

wight@giant.net.au

Ben Wight

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

Sorry but I dont think such a small upgrade justifies the price.

Ben Wight · backyard mechanic Joined: 04 Oct 2001 Posts: 946

You dont have to be sorry, you shouldn't feel pressured to buy anything.

For those people that do a bit of performance driving, and you understand the benefits of a ventilated disk, this is a cheap way of getting a package that will reduce brake fade.

You are lucky to do a single lap of a race circuit (depends on circuit obviously) with a standard brake combination before suffering brake fade, and the pedal going to the floor.

It is not a package that is designed to impress your mates with pretty gold colours, and holes drilled through them, etc, its just designed to outbrake a standard package after a few laps.

If you want wank factor, go spend $1500.

Ben

Racegem · backyard mechanic Joined: 30 Jan 2002 Posts: 987

Try your local auto parts supplier and see what a set of rotors will cost you. That's without the machining costs, and the time involved to manufacture the spacers, etc.
I think $280 is very fair.

Ben, have you fitted a wheel and tyre to check for clearance? Remembering that there are 13" x 4.5", and two different off-set 13" x 5" steel rims as well as TD SL/E alloys.

Yonnee.

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

I didnt mean that, I meant that for $280 youve only fixed halve the problem. I dont know about you but I think the standard calliper is undersize for anything other than street driving. I dont want to impress my friends with "pretty gold colours, and holes drilled through them" I would rather impress my friends by putting them in the passenger seat and show them how they work (I wouldnt get cross drilled anyway). For $99 each you can get brand new Z32 300ZX discs (280mmx30mm) abit more to get them redrilled, $395 2nd hand for callipers and a bit of work you have huge brakes that will probably never need upgrading and need extreme abuse to start fading on a Gemini. With this set up you dont even have to change the flare nut on the brake line.

Ben Wight · backyard mechanic Joined: 04 Oct 2001 Posts: 946

Well first of all, we differ in opinion about the amount of clamping force available from the factory twin piston caliper. I think that its satisfactory, but then again, its all a factor of how hard you press the brake pedal. I might be able to push on the pedal comfortably, and be applying more load than you could for example.

I used the exmaple of gold cross drilled disks as why I would buy a kit like what I am selling, I didn't actaully mean you personally have shiny gold disks and like to impress your friends with them.

$99 each for Z32 disks is pretty cheap! Though $395 for SH calipers is a fair bit, I know they cost that much, but you are not guaranteed that they will work perfectly, may need a reco. But then again, you may get a warranty. Thats one good point about my kit, you use your own calipers that you already know work ok.

You glossed over the work needed to fit the disks to a gemini hub, not to mention the different disk offset, and the construction of the brakcet needed to hold the disk. Unless you have TX stub axles, this would be pretty tricky, as you can bolt a custom bracket to a TX stub.

So after you have these bigger brakes on the front, what about the rear? You have just thrown your brake balance out the window. You would need an upgrade at the rear, or else your overall amount of retardation before wheel lock occurs wont be as high as you think.

What about the volume of a big 4 piston caliper like the Zed's? Is the stock gemini master cylinder big enough? Can it supply enough fluid at pressure to meet the volume requirements of the calipers?

These are all the sorts of things you have to think of to make a package. With what you mentioned, all you would have is big front brakes, but the performance wouldn't be great. Try braking around a corner with only front brakes and some load over the rear axle.

So you are looking at about $600 in parts for the front, and possibly another $2-500 for mods if things aren't that simple (ie. fixing brake balance, mods to master cylinder, different master cylinder), and what do you think a fabrication workshop would charge you to make up brakets for the calipers, and make a spigot for the disks to centre them on the hub, then drill and tap holes, etc, its not free.

My kits are designed to be a bolt on operation, I dont offer something that you then have to go through fabrication to install. A lot of people on these forums wouldn't be able to install a Z32 setup, and all the other assocaited mods that might be required to get it to work correctly. They might not have the tools, the equipment, or the know-how. This is where a bolt on kit is a great way for them to get the goodies, without too much hassle.

I guess I just dont like critisism that is not constructive, what you typed is similar to what I get all the time. A better approach would be to ask, for that amount of money, what performance increase is available? And i would explain further the concepts of braking and heat dissipation. Then I would explain that if you spend about $1500, you could get someone to install a pair of Zed front disks and get the whole system working well.

I am offering a solution to a brake fade problem, when the driver thinks that brake fade is their problem, not that they cant stop in a short enough distance. I remember that I could stand on my standard gem brakes, and lock the wheels/tyres. How much more brake force do you want? You are not going to slow up very quick if you are skidding down the track. Its only really if you have a soft compound race tyre, and your rolling radius is greater than factory, that a bigger diameter disk is essential.

And dont forget, you have to know how to do such a conversion in the first place, and thats part of what I provide.

Ben

TXcoupe · petrol head Joined: 05 Oct 2001 Posts: 1675

the standard brakes are great trust me. try doing 10 laps around a tight circut and try stopping from 180 to 190 kmh. the main benefit of the brake upgrade is that it wont require and other mods to fit, no engineer cert and you standard wheels wont be affected and it is vented. At $280 it more than justifies it you brake offereing is very expensive to the normal gem person. My brake up grade is costing me about $1200. Girling fourpots and brembo slotted rotors and i stil have to make up a bracket to fit the calipers and check that nothing rubs when cornering.

Gene FJ20DET · Posted: Fri Nov 14, 2003 8:03 pm Post subject: STEPS INTO THE CONVERSATION

but thats not $280 now is it??

"For $99 each you can get brand new Z32 300ZX discs (280mmx30mm) abit more to get them redrilled, $395 2nd hand for callipers and a bit of work you have huge brakes"

thats over $800 worth, so obviosly its gonna be better. u get what u pay for. and if u ask me, i honestly cant see how ben is NOT losing money on his kits cos thats fucking cheap
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Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

The next thing you will probably do is put a more powerful motor in, and if that motor is Turbo (FJ20DET for example) you will probably have to upgrade again, with I suggested you wont.

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

I guess I wasnt thinking about the master and rear brakes because I have a ZZT and these come with discs on the back and a bigger master from the factory. So its 6 of one and halve a dozen for the other for both upgrades.

Gene FJ20DET · Posted: Fri Nov 14, 2003 9:16 pm Post subject: Re: STEPS INTO THE CONVERSATION

yeahand for no this cheap up grad will be good for the dreamer untill he actuall doess (if he acutally does) the conversion

its only $280 man, its not your life saving.

and most people know what thy are planing so they would know if it was good or nit. once the silvia is sold im thinking of grabing a set for my wagon as ts just a dayly driver.

also that kit is cheaper to buy then it would be to get new pads and stock dicks and have it all bled for the average joe of the street, so even if thats why u needed its cheaper then "recoing"

if u catch what im throwing
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Gene FJ20DET · Posted: Fri Nov 14, 2003 9:18 pm Post subject: Re: STEPS INTO THE CONVERSATION

pphhwwwaaa, got spelling mistakes Razz

lol
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Gene FJ20DET

"So its 6 of one and halve a dozen for the other for both upgrades."

WTF??????
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ONLYA4 · petrol head Joined: 12 May 2003 Posts: 1114

Ben, Do you have many kits ready to go at the moment?

Because when the turbo kit is finished and i come pick it up, i might pick up one of these kits from you.

Let me know in your email next week.

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

Boith have there good and bad points.