Wilwood 1” Brake Master Cylinder

[Huw]

Has anyone fitted a Wilwood master cylinder as part of their braking upgrade at all?

I am fitting one to replace my MC (early 280ZX unit) as it’s leaking. Good original units are hard to come by and the seals sets are now unobtainable. Had two ‘good‘ second hand units fail, so now is a good time to do a little upgrading.

The question I have is to do with the check valves. The Wilwood unit has one in the rear circuit and the advice from the company is to remove it if the car does not have rear drums. The check valves are so say not needed for disks as they keep pressure in the lines and cause the pads to drag. However, the original MC had check valves in both front and rear circuits with no adverse issues. Having read a bit online in the various z forums there is a difference of opinion as to whether you leave them in or should remove them.

So long story short, has anyone got experience of doing this and if so what did you do with regard to the check valves? I’m of a mind to install them, if it was good enough for Nissan should be good for me?

Any comments from actual experience gratefully received

 

[status]

Think I’ve got a late master cylinder that came off a working car,welcome to try it if you’ve not yet got the willwood kit

 

[atomman]

I remember someone on here have lots of problems after fitting there 1" wilwood master , with rear brakes binding etc, until they realized that hadn't taken to check valve out of the rear circuit. it was a 240z but had a rear disc conversion,

 

[Huw]

Think I’ve got a late master cylinder that came off a working car,welcome to try it if you’ve not yet got the willwood kit

Thanks for the offer, I’ve got the Wilwood and machined the mounting holes ready to go. Just need a bit of advice on these check valves. But if it all goes to rats, I might give you a shout!

 

[Huw]

I remember someone on here have lots of problems after fitting there 1" wilwood master , with rear brakes binding etc, until they realized that hadn't taken to check valve out of the rear circuit. it was a 240z but had a rear disc conversion,

Thanks for the response. I read that thread and similar on the hybridz forum. Conversly there are similar instances of conversions that left the check valves in place and didn’t cause a problem. That’s why I’m a bit hesitant.

 

[Skallywag]

Has anyone fitted a Wilwood master cylinder as part of their braking upgrade at all?

I am fitting one to replace my MC (early 280ZX unit) as it’s leaking. Good original units are hard to come by and the seals sets are now unobtainable. Had two ‘good‘ second hand units fail, so now is a good time to do a little upgrading.

The question I have is to do with the check valves. The Wilwood unit has one in the rear circuit and the advice from the company is to remove it if the car does not have rear drums. The check valves are so say not needed for disks as they keep pressure in the lines and cause the pads to drag. However, the original MC had check valves in both front and rear circuits with no adverse issues. Having read a bit online in the various z forums there is a difference of opinion as to whether you leave them in or should remove them.

So long story short, has anyone got experience of doing this and if so what did you do with regard to the check valves? I’m of a mind to install them, if it was good enough for Nissan should be good for me?

Any comments from actual experience gratefully received

Hi Huw,
Checkout Francisco Gutierrez on YouTube he has a post regarding that issue. I have already bought the Willwood 1" master cylinder but haven't fitted it yet so unfortunately I can't give you a first hand account.
Hope this helps.
Cheers
Rob

 

[Huw]

Thanks Rob for that, I’ll take a look see later.

 

[moggy240]

Don't forget that the willwood uses imperial brake fittings not metric like your car

 

[Huw]

Yeh got that thanks. Got some adapters to sort that little issue.

 

[Sylv1]

Hi Huw

Got a 280zx mk1 on my 240

After a leak of fluid 2 weeks before Le Mans Classic… i ordered a wilwood AND grab a cheap aftermarket 280zx on rockauto in parallel doubting to have one in the mean time… and got the 2 LOl

I made it short and didn’t fitted yet the wilwood but I will… so follow this thread


For the metric thread, it looks that
you have to swap with OEM master cylinder

https://www.silverminemotors.com/wilwood-1-master-cylinder-260-8794

 

[Huw]

Right just to round this thread off. Job done and the pedal is nice and firm. Car pulls up with out loads of force. It’s probably not as firm as the old MC but the feel is much better. I left the check valves off with no adverse issues.

It’s a nice easy mod, only issue was having to remake the hard lines to the MC as the lines were a bit too long with the adapters I fitted to overcome the thread issue. The original caps also fit on the new fluid reservoir, which is a nice touch.

Only real kicker was the £103 bill for fuel to test the car….

Old MC




New

 

[Huw]

Here we are again, not even 12 months down the line and very little use and I’m having to replace the master cylinder again due to a leak overwinter. Stripping the thing down I found large and quite deep score marks in the master cylinder bore. Which allowed the fluid to bypass the seal and leak all over the chassis leg paint work whilst in storage.


Don’t know where the contamination came from to do this. The fluid tank filters were clean so I can only assume there was something in there from manufacture. I have written to Wilwood but not yet received an answer.

Have fitted yet another unit as this one is too badly scored. I did strip the new new unit to check there was no debris in there from manufacture. Fingers crossed.

One of those things I guess.

 

[jonbills]

I'm sure I've read quite a few negative comments on the US forums about Wilwood master cylinders