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Finished brake setup!
turbodisplay - 30/11/08 at 10:11 PM

Finished my brake calipers, ap racing calipers from a VX220, spaced 5mm to accept a 345mm * 30 disc to replace the 288mm discs i was going to use.


Guess the difference in weight going from 288mm with cast iron caliper to 345mm with ali caliper.

Darren

Image deleted by owner

Image deleted by owner

Image deleted by owner


mookaloid - 30/11/08 at 10:30 PM

Not wishing to be critical but you are only covering about half the available area on the disc - surely it would be better to get calipers which are actually supposed to fit on a disc that size?

If you use the right calipers you would actually be using the discs to their potential

Cheers

Mark


blakep82 - 30/11/08 at 10:43 PM

^ yep, that was my first thoughts too.


NS Dev - 30/11/08 at 10:46 PM

are they not vx220 rear calipers?


Bob C - 30/11/08 at 11:27 PM

Go on, I'll guess you are weight neutral...
Personally I can not see any issues with not using all the available swept area of the disc. (But I might want to introduce some webbing in the bracket you've made ;^))
You'd lose a ton of unsprung weight by engineering ally disc bells - those look like mighty heavy discs, APracing & Wilwood both sell brake discs intended to bolt onto ally bells, but they do cost a bit, as does the ally stock to machine the bells.


turbodisplay - 30/11/08 at 11:50 PM

1.2 Kg up, so not much, the cast calipers were 6kg!

The proper calipers were cast iron so weight far too much.

The original fitment only used some of the swept area on the vx220 as well , it is the front calipers. I know they look tiny, mainy due to the size of the discs.

My reason for the size increase is to prevent fade, and to increase leverage (so I can hopefully remove the sevo) . I plan to use the car on the track, so fade could be a problem on 288s. Even with high temp pads the fluid will become the weak link.

The bracket is stainless so should be strong, as is the spacer.

Darren

[Edited on 30/11/08 by turbodisplay]


Rod Ends - 30/11/08 at 11:54 PM

Pads gripping the discs at the outer edge gives greater leverage.


clairetoo - 1/12/08 at 06:31 AM

Those brackets may well be strong enough - but they dont look too rigid .


Antnicuk - 1/12/08 at 08:02 AM

get some AP racing 551 or 600 fluid, tyou wont boil it.

out of interest, how heavy is your car?


nick205 - 1/12/08 at 09:19 AM

quote:
Originally posted by turbodisplay
The bracket is stainless so should be strong, as is the spacer.

Darren

[Edited on 30/11/08 by turbodisplay]



Being stainless doesn't make them strong(er). Stainless is lower in tensile strenght than most grades of steel. Hence why in applications where tensile strength is important stainless fasteners aren not used.

Difficult to see exactly how they're made, but my guess is the extension tubes will flex in use and cause brake judder. I'd expect them to crack eventually too.

Personally I think they'd be better made from decent grade steel and webbed/braced to each other and the mounting bracket. Better still make the whole thing out of a single peice of metal. It does look like your handy at metalwork, so should be do-able.

(just my 2p worth )


britishtrident - 1/12/08 at 09:39 AM

quote:
Originally posted by Antnicuk
get some AP racing 551 or 600 fluid, tyou wont boil it.

out of interest, how heavy is your car?


Avoid racing fluids as because the absorb so much moisture they need changed very frequently to preserve the boiling point and prevent corrosion..

Normal DOT5.1 changed at least once a year is highly unlikely to boil.


adithorp - 1/12/08 at 12:30 PM

I'd have to agree that those extentions are going to cause judder at the very least. I expect they'll bend though. All the energy in the car is going to be trying to bend them every time you brake!

adrian


flak monkey - 1/12/08 at 12:36 PM

You ar eless likely to get fade if you can use the full area of the disc as you have more pad area to dissipate the heat. You will also get marginally better brake performance.

I would beef up those brackets if I were you. Also be wary of how prone to fatigue stainless steel is.

What is the weight of your vehicle? If its under a tonne I would expect you will never get enough heat into those disc to make the pads work properly.

I don't understand the fact the original calipers and disc were too heavy, yet the set up you have replaced them with is heavier still? :-S

David


turbodisplay - 1/12/08 at 01:16 PM

I`m guessing it will tip the scales at 900 - 1000Kg.

Using 5.1 fluid. With mintex 1144 pads.

I think you guys have a point about the flex, it does seem quite firm, but it probally is worthwhile increasing the strenght, before i was not 100 % of the exact size required for the fitting.

2 x 12.9 bolts joins the caliper to the main fitting through the spacer.


Darren


mad-butcher - 1/12/08 at 06:40 PM

Wheel Rim Clearance ?


turbodisplay - 1/12/08 at 07:22 PM

Its tight! Using 17" rims as they were cheap from flea bay.

The current stick on ballancing weights just catch, but as i am replacing the tyres the new weights will be thinner, and or placed so it is not near the caliper.

Darren


turbodisplay - 1/12/08 at 08:01 PM

I`ll look at getting the bracket made in mild steel.
Is stainless worse than high grade ali for fatigue? I`ve seen many alloy brackets, hence i thought stainless would do it.

Thanks
Darren