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Hi All,

I have a leaking master cylinder in an NB8C. I can't find a kit to rebuild, and new is over $1k ex japan.

What do others do with this part when it needs love - do I need to just send it to brake and clutch place for a reco?

Cheers,

Hanson

My approach would be to talk to a few local brake and clutch guys - they have the contacts and knowledge on fixes and sources for components - it might be a very easy fix. Rubber seals etc are often standard items i.e. common to other models.

You have PM.

Before you pull the trigger on a new MC, ask yourself whether you want to do something different. This is the time to change to a different MC, should you wish, rather than later when it might involve another MC purchase. Without going to a pedal box/dual MC setup, changing the MC for one with a different bore size has been discussed on MT.net, and )I think) on here.

greenMachine wrote:You have PM.

Before you pull the trigger on a new MC, ask yourself whether you want to do something different. This is the time to change to a different MC, should you wish, rather than later when it might involve another MC purchase. Without going to a pedal box/dual MC setup, changing the MC for one with a different bore size has been discussed on MT.net, and )I think) on here.

Thanks GM,
I don’t know enough to know if I would benefit from a different MC. So far, I’ve been satisfied with the stock system with Winmax 6.5 pads. The leak is also in the road going car, which I am not planning on modifying any further now that the Black Rat has begun.

Do people change the MC size other than to compensate for changed calipers or booster delete?

TBH, I can't remember the details. I do remember I bought the Wilwood 1in (I think, details blurry) MC for my racecar, never installed it and on-sold it some time ago. I wouldn't buy it for a road car unless it was a serious dual-duty car, as I recall it was all about brake pedal feel at the limit.

I have a few spare brake masters (NA6) at home, you are welcome to have. Have the boosters as well.

Na6 vs nb size is different. I think 7/8 vs 15/16 but don't quote me on the that.

Get in touch with slacks creek brake and clutch or bhss in capalaba.

One of them stainless steel sleaved my brake MC, the other did the clutch.

I would recommend this route. Not as cheap as getting a second hand MC, but makes future refurbs a cheaper.

Also, a company called honed developments in melb have a brake booster delete that looks like a neat little unit. Either for the track car, or the road car.

Stainless resleeving is the way to go if you can get it done easily and you're staying stock. Otherwise I'd just go to your local parts place. MCs are very low tech. You just need one that fits. Being able to swap it easily with them without any fuss is a plus.

If you do decide to replace it with a new one there is another option.

https://www.mx5parts.co.uk/brake-master ... rrency=AUD

I have used mx5parts a few times, they are fast in sending the item and reasonably priced (when the Aussie dollar had more buying power).

J