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Steel dogbones would be like 600g each. I'd look into aluminium ones if you are able to CAD them up yourself. Would save a heap of weight.

But I guess if you're running these things then you're already not really worrying about weight. :thumbsup:

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Steel dogbones would be like 600g each. I'd look into aluminium ones if you are able to CAD them up yourself. Would save a heap of weight.

But I guess if you're running these things then you're already not really worrying about weight. :thumbsup:

CAD stuff is easy. Hard part is finding a CNC shop to do them at a reasonable price. Any ideas?

its not a race car, so every kg isnt critical.

here is the rear setup

IMG_0321.jpg

just waiting for the spacers between the halves of the caliper to be machined then i can install them for a trial before i strip them down for coating. this will let me work out the master and bias setup.

will be tested for bias ratios also, so will have actual numbers to show.

CAD stuff is easy. Hard part is finding a CNC shop to do them at a reasonable price. Any ideas?

there is a guy who just got a CNC mill a few months ago - posted in the fabrication section - he might be willing

CAD stuff is easy. Hard part is finding a CNC shop to do them at a reasonable price. Any ideas?

Nah sorry. :(

Here are some rough brake bias calcs to further what Roy said:

R32 GTR OEM 69.2% Front

Evo Front GTR Rear 73.3% Front

Evo + 355mm Front GTR Rear 75.3% Front

So yeah will definately cause issues. Does anyone have the piston size of the Evo rears so we can throw that into the mix?

Steel dogbones would be like 600g each. I'd look into aluminium ones if you are able to CAD them up yourself. Would save a heap of weight.

But I guess if you're running these things then you're already not really worrying about weight. :(

The EVO calipers I bought feel alot lighter than the r33 calipers I have on my 32gts-t.... A 2 piece 355 rotor isn't going to be much heavier than the stock iorn rotor.

I'm not a huge fan of welded steel for brakes.

J.

Yeh, welding anything on the brake bracket has its limitations. Firstly, after welding you would want to machine them again. Remember that you can feel brake vibrations through the brake pedal and steering wheel with as little a 0.0005" movement/uneveness in your brakes!!! SO if you weld something it is going to distort, so should be machined again. Which raises the question, why machine it, weld it then machine it again....fine if you are doign it all yoruself. But if you are paying it makes sense to just machine it right the first time.

Secondly, if you are going to be welding anything in your brakes i suggest it is done by a qualified welder to a qualified weld procedure. What that means is that similar welds have been done by an experienced welder good enough to do good consitant welds, and that they have undergone tensile tests, xray tests etc to ensure the weld is as strong, if not stronger then the parent metal. If you are welding something that is subject to the temps, the cyclic loads and the torsional stresses that a brake mount is subject to, then you want to be sure that you are using the correct weld prep, current, wire, purge gas etc etc so that the thing doesnt fail.

There are lots of variables with brake setups. And there are lots of things to consider with brakes and what is an upgrade. Generally the main things are managing heat which is mostly rotor type and size, and caliper rigidness. You then have to match your piston diameters to the rotor size and bias that you are after. Some calipers are better then others because they are more rigid, have better pad cooling, run external brkae line meaning they cool the fluid a little better. Some have better seals, some have pistons that dissipate heat better which means pad temps dont get conducted to brake fluid.

There are a few consideration, but generally, bigger the rotor you run the more bias you are running. The bigger the piston sizes the more bias you are running. So if you are going bigger rotor its not unusual to go smaller pistons to make sure bias and pedal feel is maintained. Others do use larger pistons with larger rotors, only small %s and in cars like R32s etc the Brembo range of caliper work well as they tend to be a bit of a handful in the rear under brakes and moving the bias forward with bigger rotor and pistons means that the car is often more settled under brakes.

I am a sucker for nice big brakes, but its important to remember that you can end up with brakes that are so big that all they do it leave you with unwanted mass hanging off your suspension, so much cooling that day to day driving you need to consider what pad to run as you may never get the required temp into them. You want to install as small as a kit as you can, and there are some good OE setups around that can be engineered to fit....but you need to pick the right kit to try and make work

Be interesting how this kit comes together.

Edited by Roy

Yeah... waht Roy said.

The r34 gtr master is the same diameter and almost the same stroke as the EVO IV master cylinder (I'm planning on using a 34gtr master cylinder). The EVO bias is a little too rear for a 32 gts-t. I'm planning to go up a size in front rotor (EVO front rotor is 320mm, I'm going with a 354.6mm front rotor) and same diameter in the rear (300mm). I'm hoping this will bring the bias forward enough... if all else fails I'll just install a bias adjuster to cut a little more off the rear.

Just have to design and fab some nice 6000 series billet adapters.

J.

Any reason apart from price why people are using the EVO Brembo?

I found 2x full sets while I'm here in Florida and picked them up for 700 bucks. I cant buy r33 brembo's for that. Plus they're for my little r32gts-t not my GTR.

Both sets were from warranty replacments because the factory paint was messed up. Apparently it was fairly common for one of the production runs for the paint to peel on the calipers.

The seals and pistons looked perfect.

I figure that as I'm going up in front rotor size, I'll need to get adapters made either way. Also the pistons on the EVO calipers look to be a little bigger than the 33/34 brembo's, the have the external pressure line, there is a huge choise of pads and heaps of data/testing from the US EVO guys.

I can also run wider disks.

But it's mostly price.

Justin.

We did this conversion years Ago. The setup is still floating around on one of my old GTR's doing light track work.

You will need an aftermarket 1 inch master with no prop valve and an external prop valve to get bias even reasonable.

Also the weight of a skyline in high load corners caused massive pad knock off no matter how we did the adaptors. Problem was consistant on 3 different GTR's too.

It won't work out cheaper once you go through the hassle of sorting it out. I ditched the evo's after having pretty much every problem roy has identified plus the pad knock off issues.

We did this conversion years Ago. The setup is still floating around on one of my old GTR's doing light track work.

You will need an aftermarket 1 inch master with no prop valve and an external prop valve to get bias even reasonable.

Also the weight of a skyline in high load corners caused massive pad knock off no matter how we did the adaptors. Problem was consistant on 3 different GTR's too.

It won't work out cheaper once you go through the hassle of sorting it out. I ditched the evo's after having pretty much every problem roy has identified plus the pad knock off issues.

So the flex mid-corner was in the actual caliper?

I remember seeing some data someone measured on their Evo 8 circuit car with new OE Brembo calipers. When they were brand new the caliper flex (measured with a dial indicator) was ok but it quickly deteriorated over the course of a season of track days.

Edit: Actually disregard that. I have no idea if it was 'ok' to begin with because I have no idea how much is ok. :blush: They just got a lot worse with time.

We did this conversion years Ago. The setup is still floating around on one of my old GTR's doing light track work.

You will need an aftermarket 1 inch master with no prop valve and an external prop valve to get bias even reasonable.

Also the weight of a skyline in high load corners caused massive pad knock off no matter how we did the adaptors. Problem was consistant on 3 different GTR's too.

It won't work out cheaper once you go through the hassle of sorting it out. I ditched the evo's after having pretty much every problem roy has identified plus the pad knock off issues.

can we have some more details on the setups you ran? rotor sizes, pads you ran, rear also?

So the flex mid-corner was in the actual caliper?

I remember seeing some data someone measured on their Evo 8 circuit car with new OE Brembo calipers. When they were brand new the caliper flex (measured with a dial indicator) was ok but it quickly deteriorated over the course of a season of track days.

Edit: Actually disregard that. I have no idea if it was 'ok' to begin with because I have no idea how much is ok. :blush: They just got a lot worse with time.

I think you will find the flex didnt come so much from the caliper as the mount. Many that i see look as though they would "twist" if subjected to loads. Thats why i always preferred to teh R32 GTSt 324mm upgrade over the R32 GTR/R33 GTS25T upgrade as the change from 280 to 324 makes for a far sturdier bracket then 296 to 324. The Evo which runs something like a 320mm rotor from memory to 355 is better but still not as bulky as the 44mm change in radius of the R32 GTSt kit

Guys Roy and Risking are on the money, by the time you stuff about endlessly with brackets, mcyl, valves, custom hats etc you're so close to the cost of APs it's not funny abd they're a 'bolt on and be happy' proposition. Also try these:

http://www.stillen.com/product.asp?id=APBR...p;model=SKYLINE

US $2500 plus freight even at $400 and you're there.

Just my 2c.

Those APs that Stillen use are the CP7040 calipers which are not as good as the CP5555, and dont use AP rotors, but there own branded rotors. (which are probably still good things) At the money they are still decent value given current exhange rate

I stay stick with it Chris, you may find that the balance isnt too bad and easily able to be improved with a bias valve. I dare say all the parts you are pulling together as a kit will mean that it will be rather easy next round if you want to try again with a different caliper. WHen you have the rotors etc all running drop me a line interested to hear how it works for you....IF you are not happy I have a few ideas of other calipers that are cheaply available that may work well

Edited by Roy

bias valve i want to avoid for legal reasons, but can always get the factory one revalved to the bias we work out with the adjustable unit. but im almost 100% convinced the valve will be required with the alloy hats on the rear and the 355mm rotors

fronts are ready to install, just have no time to get the car into the shop and start pulling shit apart.

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