I know this is a bit of a thread dig, but I thought the research I did for my recdent brake upgrade may be of interest to others, So here goes..................
I started out by hoping to fit some larger rotors but keep the stock calipers (and move them out wards by using a modified bracket). A lot of people hyave done this on VT's to VZ's I think??
Larger rotors (discs) if you can do it, are a good way to get a gain without going “over the top” in cost. Larger rotors offer the following advantages:
1.They exert a larger torque on the hub when slowing, so yes, it will stop better. The moment of the force is increased due to the larger radius of its location (force x radius);
2.offer slightly more mass to prolong the heat build up / release of the metal. It may give slightly better cooling.
3.A mechanical advantage is obtained as the calliper has greater leverage than it did being further from the centre of the disc.
4.If the calliper is mounted further out but with the standard pad, the “swept area” of the disc is greater as the diameter of the disc is greater at that point (pi r-squared applies here as it is the area the pad sweeps across that makes it work).
Some other things to remember:
1.You need to space the calliper further out to accommodate the larger disc.
2.A larger disc will not fit with the calliper in the standard location.
3.when fitting larger discs, the largest disc that will fit that calliper is the limitation;
4.To move a stock calliper outwards an adaptor bracket would be needed. Adapter brackets are frowned upon unless they have been ADR “complianced” or an engineer’s certificate obtained.
5.This is commonly done on earlier models such as VT’ and Vx’s. The largest disc for example that will fit a VT standard calliper is bigger than the 298mm standard disc. A 330mm disc will fit the VX with the calliper spaced out to suit.
6.The difference between a 296mm disc and a 330mm disc with the same calliper and pads is quite big.
In doing this research, I also called a few brake specialists. Here is what I have been told:
- a few places have made mounting brackets for VTs and other earlier model but not for VEs.
- one place told me that reason nobody has done this is that the stock VE V8 callipers are currently fitted to the largest disc they were designed for. That is they will not fit on a larger diameter disc even if the calliper was relocated.
- an after-market calliper would need to be used.
So I ran into a dead end on this because I want to keep my Speedy Cheetah wheels.
ADR COMPLIANCE and ENGINEERS CERTIFICATION
I may be wrong on this, but from what I understand, a general "ADR Compliance" is unlikely for aftermarket brakes (or adaptors or components), unless they were an actual new car option for that particular model. If going to bigger brakes I would definitely want to get an engineer’s certificate. The NSW RTA has a list of recognised engineers on their web site.
The trick is to get them certified by an engineer as a "one-off" for your car. As an extreme example, Brembo’s which are ADR Compliant for HSV's were not available when new for most other cars, so they are not "ADR Compliant" in general - only for HSV's and the like.
It looks like I won't be able to do what I had hoped with the VE stock callipers. However the info should also be of great interest to those with earlier models like VT's and VX's etc. It seems that this type of mod is common on them because the stock callipers are actually designed to take larger disc rotors.
NSW RTA - Brakes
Brake systems must not be modified such that the brake performance is reduced or that the risk of failure of the brake system is increased. Brake discs or drums must not be machined beyond the reconditioning limits set down by the manufacturer. When brakes are upgraded using components or systems which were not standard options for the vehicle, an engineering certificate is necessary to attest to the adequacy of the new system, eg: hydraulic fluid sufficiency, balanced braking on all wheels, brake pedal pressure limitations and braking performance.
BRAKELINES.
I also found some interesting info about ADR'd Brakelines on a WRX forum in Perth. It seems to clear up some myths in regards to ADR approved braided brake lines but would need to check the info for relevance to NSW. The text is below:
The old ADR 7 meant that all braided lines had to pass a whip test.. and without the ADR approved sheaths over the line near the end fittings, they would not be ADR approved.
Like this..
This is now OBSOLETE.
The new regulation is....
"ADR 42 - General Safety Requirements - The function of this Australian Design Rule is to specify design and construction requirements to ensure safe operation of vehicles.
Vehicle Standard (Australian Design Rule 42/04? General Safety Requirements) 2005
Compilation: 1 (up to and including Vehicle Standard (Australian Design Rule 42/04? General Safety Requirements) 2005 Amendment 1). Date: 12 October 2007.
BRAKE TUBING AND BRAKE HOSE
Flexible hydraulic brake hoses, air or vacuum brake tubing and air and vacuum hose, flexible and hydraulic power hose between the Brake Power Unit 31/00 or Brake Power Unit 35/00 and the master cylinder or its equivalent must conform to SAA, SAE, BS, JIS, DIN, ISO or ECE Standards specified for flexible brake hoses, air brake tubing or hose or vacuum brake tubing or hose or hydraulic power tubing or hose and be fitted to the vehicle as to prevent chafing, kinking or other mechanical damage under normal motion of the parts to which they are attached”.
This all means that basically, any braided hoses which come from one of the reputable manufacturers i.e. Goodridge, AP, etc, would be ADR approved. Other manufacturers may also comply if they specify that they are built to one of the above standards. To simplify it, any braided line must fall under one of the other world standards to be ADR approved. They don't necessarily have to look like the image above to be ADR approved".
I am told that braided brake lines are good when the brakes get hot- you tend to keep more pedal feel as they don't expand as much. Overall performance gain is probably minimal, but they do look good and certainly feel nice under pedal.
BRAKE PAINT
Some paint their stock callipers. One guy recommended VHT Enamel 288 degree C Engine paint. Available from Repco (about $16). The paint actually looked better after he bedded in the brakes. This helps bake the paint on and has actually brings them up quite a bit shinier (the instructions say this will happen if you baked the item @ 200 degrees C in an oven).
4 and 6 PISTON OPTIONS
Although they were outside my original brief and are beyond my braking requirements, (but because of their good appearance) I looked at a number of performance brake brands to see if they would fit under my Speedy Cheetahs. None fit (Harrop, HSV Brembo's including the newer Redlines and also AP). Also none of those companies seem interested in modifying anything to make them fit.
I obtained templates/profiles from Harrop that can be printed, cut-out and held against the hub face of the wheel to see if they fit. I would be happy to send an email with attachments of these if anyone PM's me.
I did find a company (Duspeed) that would modify a set of race brakes (VTTR) to fit. But like other similar 4 or 6 piston options, this is a costly exercise for a road car that never hits the track. However, they do look great and have been on a number of show winning cars. They seem like amazing brakes used by a number of people for track work etc. I test drove a VE Senator with them fitted and the brakes were fantastic.
Duspeed modifies the "hats" in the 3 piece brake disc so the disc moves inward a bit.
I have also been told that Alcon 365mm brakes fit behind standard 19" SSV wheels, and also standard 18" Series 1 Calais wheels if the balance weights are re-positioned. I did not try Alcon with my wheels as they are WAY above my budget.
MY OWN DECISIONS
I went with DBA 4000 T3 rotors, Pads - QFM HPX (police spec), braided lines (mainly for appearance) and a really good quality DOT4 brake fluid. I got the parts etc to do this for a total for all four wheels of about $1000 on sale. I also bought some Loctite for the caliper bolts etc. Excellent value and everything is classed as "replacement parts" for OEM so no engineers certificate required.
Fitting the rotors and pads was very easy. It took only about 3 hours with a couple of breaks.
Hope this helps others!!
