Brake Upgrade clarification??

[Lucky_Luke]

Hey everyone,
Im looking to upgrade/convert my 1.6L brakes to bigger ones.... finally!

I have been reading several of the other old forum topics about this but its beginning to confuse me..
Can any of you brake guru's shed any specific details on the following queries??
As theres nothing worse than buying a heap of bits and finding that they dont fit..

1. If i purchase a set of Front and Rear callipers and discs from an NA8 namely a late 1993 -1997 model will they definitely bolt straight in and replace the 1990 NA6 calipers and discs??

2. If i only get the fronts changed, will i need to do anything with the bias valve? such as swap for an NB valve as mentioned in previous topics, the vibe im getting from the other topics is that with this conversion you can back off the front and give more to the back rotors, to elim the NA6's heavily front favored bias..

3. If i replace all four corners with NA8 brakes will i still 'need' a different brake bias valve??

4. Is there any obvious differences between the na6 and NA8 calipers?? I found a spares place that 'supposedly' has a set of NA8 brakes and when i go in there id just like to be able to look for something specific and say yep they're NA8's and they'll fit... ill take em!!
Ive gathered from a different topic that I can measure the rotor sizes for the NA8 which should be 255mm [front], 250mm [rear] ??

Im going to see the calipers tomorrow and take some pics ... is there any bits i can look at to tell whether they're in good nick or not?

This is a pic from the silver mx hukunas webpage.. if this is a really accurate rep of an NA6 to NA8 front disc comparison it Looks like theyll make a rediculous improvement!



Thanks for any help peoples!!!
Luke.

[Mr_Q]

The picture looks about right - the later model are just slightly bigger than the old NA6 ones, aren't they?

I did the disc, caliper and brake line swap from a non-ABS NB8B onto my NA6 and they worked perfectly. I didn't swap the bias valve but never had any issues with it.

[Matty]

1. If i purchase a set of Front and Rear callipers and discs from an NA8 namely a late 1993 -1997 model will they definitely bolt straight in and replace the 1990 NA6 calipers and discs??

Assuming that the calipers come with the brackets attached, then yes.

2. If i only get the fronts changed, will i need to do anything with the bias valve? such as swap for an NB valve as mentioned in previous topics, the vibe im getting from the other topics is that with this conversion you can back off the front and give more to the back rotors, to elim the NA6's heavily front favored bias..

You don't NEED to (ie the car will work fine without it), but it's a big improvement to do so.

3. If i replace all four corners with NA8 brakes will i still 'need' a different brake bias valve??

see above

4. Is there any obvious differences between the na6 and NA8 calipers?? I found a spares place that 'supposedly' has a set of NA8 brakes and when i go in there id just like to be able to look for something specific and say yep they're NA8's and they'll fit... ill take em!!
Ive gathered from a different topic that I can measure the rotor sizes for the NA8 which should be 255mm [front], 250mm [rear] ??

The "fingers" on the 1.8 calipers are a little longer.

Also, the Caliper marked "L" and "R" will have the slider pin sizes swapped top to bottom relative to the 1.6 brakes (ie, 1.6: larger pin is at the top. 1.8: larger pin is at the bottom. I think - or vice versa)

[Lucky_Luke]

Ah ha... cheers guys... very much appreciated!

Out of interest... is it a big deal to only change the fronts or is it really necessary to change the backs as well??
I imagine with the bigger rotors on the front and not on the back with an unchanged bias this may cause issues.. Mr_Q did u do both front and rears?

Also is the NA8 caliper itself bigger than the NA6 with a larger piston too??

I have also seen some conversions done just keeping the standard NA6 calipers and just using the bigger rotors and the NA8 calliper brackets.
http://www.miata.net/hakuna/0003/aindex.htm
But this surely wouldnt be that much of an improvement as the NA8 calipers id imagine would have the added benefit of bigger pads and more clamping force..??

Luke.

[Mr_Q]

Mr_Q did u do both front and rears?

Yeah, I did the whole lot in one hit.

You should be able to find a complete set in good condition for well under $1000 (I think I paid about $800 for my set that came off a car with <20,000kms on it). If you've got the lot it's a really straight forward exchange - just unbolt the old ones, bolt on the new ones and do the brake fluid.

[adamjp]

Whilst I have not actually done the conversion, it is my impression from the many things that I have read, including the Keith Tanner book that tells you how to do this, the calipers are the same from NA6 to NA8.

The caliper mounting brackets are different, the rotors are different, and the pads are different. The calipers are the same. You get better effort for your brakes because the bigger rotor allows a better mechanical moment to be applied (more leverage) with a bigger pad (more grip).

[Matty]

Keith is wrong then.

The mounting pin spacing is the same.
The piston diameter is the same.

The bleeder valve is on the other end of the caliper (relative to the correct slider pin sizes).
The fingers are most definitely longer (try mounting a 1.8 caliper on a 1.6 bracket)

[adamjp]

Matty,

The NA6 (89-93) and NA8 (94-01) calipers are the same. They are reversed in their application to the car, but they are otherwise interchangeable. When upgrading you must place the NA8 Left bracket on the RIGHT side of the car, and visa-versa. If you wish to have them the same as installed on an NA8 you simply change the calipers over. However it is a lot of work and it will make absolutely no difference to the effect that they have.

Try Miq Millmans http://www.bigllama.com/miata/brake/bigbrake.htm
And the Hakuna site http://www.miata.net/hakuna/0003/h0001.htm

NB8 (01-05) calipers are visually different and clearly have a larger distance between the mounting bolt and the centre of the piston.

Luke's question related to NA8 upgrade, not the NB8B upgrade.

Like I said, I have not done it, but I trust to the guides read by many without alteration. As for the Keith Tanner book, I agree it is possible for it to have something wrong, but since Keith is a well respected Miata modifier, working for Flyin' Miata, I trust to his book and the corrections sheet he has published for the small errors in the book.

Did you install NA8 or NB8 rotors and calipers?

[Lucky_Luke]

Hey Guys, Thanks for all your input , Im about to go to see this wrecker dude so ill take some pics and show you what they look like...
What exactly are these longer fingers we're talking about here?

I havent pulled my brakes apart before so im unsure of the specifics you guys are mentioning .. longer bits and hole spacing etc but im sure after checking these brakes out, Ill have a better idea...

But im getting the general vibe that if i upgrade i should prob do the rotors as well as the calipers, and front and rears, and make sure i get the brackets.
These guys want $125 for each corner.. caliper and rotor..( ill soon find out whether thats pad and bracket etc included, but i imagine it would be) that sounds reasonable .. from the prices ive seen around.

Luke.

[Matty]

The fingers are the two prongs that pull the outer pad onto the disc.

[Lucky_Luke]

Ah... the fools...they were 1.6L calipers! after asking them several times \" are u sure they're 1.8L brakes... yeah yeah they are!\" damn it.. and they were rusted to hell and back too... I'll have to keep my eyes peeled !!

Cheers for your help guys!