3gress wrote:Where are you at with regard to booster/master considerations? What are your thoughts on The later nb abs combination being a possibility with judicious choice of brake pad?
I'm not an expert and have no experience so not sure my 2 cents is really worth anything. What I'd like to do and what I will do are two different things, at present I'm looking at going back to uni to study Engineering or Medicine so saving for a slush fund.
However what I would be doing is using a Master Cylinder from a BJ, these are the same ratio as NB8B Masters (15/16) (apparently aus delivered NB8As are 7/8ths like NA.). But on a BJ there are only two exits from the master, which in turn feed the ABS module, one for rear and one for front.
The rear takes care of itself as drivers side rear wheel from memory has a splitter which splits the pressure between the two rear wheels. The front is where you need to make alterations, here you would need to add a splitter so that you can feed the lines for front left and front right.
Picture of master:
As you can see the tank also has a port to feed a clutch master, so we can ditch the seperate tank and move to an astina master. This to me would be the best setup overall.
In conjunction with this I'd use a NB8B booster (for reasons that are at the bottom of post):
Keith wrote:1990-00: 4.74:1 <- this is a bit approximate, as Mazda gives a range of output pressures as acceptable
2001-05 non-Sport and Sport with ABS, except for MSM: 9.7:1. Yes, that's about double. This booster is visibly fatter, and I suspect it has dual diaphragms inside instead of a single.
2001-05 Sport without ABS and MSM: 6.4:1
There's more to it than the boost ratio, of course. That larger master cylinder in the 2001-05 cars means less pedal travel and more effort with a given caliper size. Taking both the master cylinder size and the boost ratio into account, here's how it shakes out.
1990-97:754-796 psi of line pressure for 44 lb-ft
2001-02 non-Sport and 2001-05 ABS: 1038 psi of line pressure for 44 lb-ft on the pedal
2001-5 Sport non-ABS and MSM: 638 psi for 44 lb-ft
Sport cars (all of them) use larger pistons in the front and rear calipers, so the amount of braking force is going to change. But from this, we can tell that the 2001-02 non-Sport cars will have the pedal with the least travel of any stock car, but should also have the lightest touch.
There are some interesting interchange options here. I have an MSM master and booster in the Targa car. If I wanted to make the brakes require a little more effort, I'd swap in a booster from a 1990-00 car.
Link:
http://forum.miata.net/vb/showthread.php?t=363284The reason that I'd use the NB8B booster is that QLD law regarding brakes states:
Magpie wrote:For Queensland
Brakes
Replacement brakes that are offered by the manufacturer as an option for that model of vehicle may be fitted without specific
approval. For such conversions, all components must be identical to those of a vehicle originally produced with the optional
brakes.
Brake systems modifications must not reduce braking performance or increase the risk of brake failure. 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 Approved
Person must be engaged to certify the adequacy of the new system, as issues such as hydraulic fluid sufficiency, balanced
braking on all wheels, brake pedal pressure limitations and braking performance must be considered.
For further information please refer to the LG section of the National Code of Practice for Light Vehicle Construction and
Modification.http://www.tmr.qld.gov.au/Safety/Vehicle-standards-and-modifications/Vehicle-modifications/Light-vehicle-modifications.aspxLooks like I will have to get my NB8B brakes certified. Sort of thanks Madjack
Quoting Magpies post from here:
viewtopic.php?f=30&t=70078&start=45The issue is the braking system we are moving too were originally *only* fitted to cars with ABS. With using NB8A or NA8 we can get away with no ABS rather easily as to my knowledge the NA8 in australia never came with ABS.
Having said that, quick update re car. Following has been completed:
- Engine Mounts & Sump Collected
- Engine & Gearbox installed.
- Tailshaft & PPF bolted up
- Exhaust bolted up.
- Modified clutch line to work with B2200 clutch slave
- Redid fuel lines using E85 compliant hose
- Mazdaspeed Short Shifter installed.
. Saw your post, but had already ordered replacements from Automotive Plus. 
too funny 
[sold]
