Calling for a 17mm Master Cylinder, Don't like the 19mm!! Options

[Artfrombama]

Replaced the OE 17mm that came on my 74 because it was leaking out of the rear. Replaced it with the 19mm that is currently offered as a replacement.

Not happy with the increased pedal pressure required to stop the car, almost scary in a panic situation. No pedal modulation.

I would like to return to a 17mm unit but there seems to be no more out there, does anyone have a source? Is someone in the parts supply chain able to reproduce these parts reasonably?

Thanks!

[rjames]

Replaced the OE 17mm that came on my 74 because it was leaking out of the rear. Replaced it with the 19mm that is currently offered as a replacement.

Not happy with the increased pedal pressure required to stop the car, almost scary in a panic situation. No pedal modulation.

I would like to return to a 17mm unit but there seems to be no more out there, does anyone have a source? Is someone in the parts supply chain able to reproduce these parts reasonably?

Thanks!

Interesting as I didn't think the difference was very significant when I replaced my ATE 17mm with an ATE 19mm. Is everything else in good order (rear adjustment set correctly, pads/rotors, etc.)?

Even though they are NLA, 914xr75 recently posted that they got a 17mm from Pelican. They don't have any on their site, but you might try calling them.

[Shivers]

I did the 19 mm M/C and some of Eric Shea’s sticky pads for the brakes. Sorry can’t remember the name, I was lucky to remember Eric’s last name. They worked great together. Hope you find a 17 mm.

[mepstein]

I’m with you. I’ve tried both and prefer a 17mm on a stock 914-4. I last bought a 17mm MC in 2014. I paid retail at the time and it was one of the last 17mm ATE brand mc’s that I ever saw for sale. Perhaps there’s a source but I’m unaware of one.

Even with the firmer feel of a 19mm MC, your brakes shouldn’t feel scary. Make sure your soft lines are not old, they will swell and narrow the fluid passage with time, making braking harder and less effective. Call Eric Shea at PMB Performance and get his suggestion on brake pads. I believe he’s a big fan of Porterfield pads but he might have a suggestion that makes you feel better about your brakes. He might also have an alternative MC that can be used in our cars.

[StratPlayer]

Getting ready to install a 23mm MC, recommended by PMB. BMW 320i up front 914/6 rear calipers.

[Artfrombama]

I’m with you. I’ve tried both and prefer a 17mm on a stock 914-4. I last bought a 17mm MC in 2014. I paid retail at the time and it was one of the last 17mm ATE brand mc’s that I ever saw for sale. Perhaps there’s a source but I’m unaware of one.

Even with the firmer feel of a 19mm MC, your brakes shouldn’t feel scary. Make sure your soft lines are not old, they will swell and narrow the fluid passage with time, making braking harder and less effective. Call Eric Shea at PMB Performance and get his suggestion on brake pads. I believe he’s a big fan of Porterfield pads but he might have a suggestion that makes you feel better about your brakes. He might also have an alternative MC that can be used in our cars.

New flex lines, kits in all four calipers.

[Jack Standz]

We have at least two failed 17mm master cylinders/cores and 1 NOS 17mm one (for our '72 project).

Agree that it would be best if a rebuild kit could be offered by one of our sympathetic vendors. Because there is a difference between the 17mm and 19mm and other sizes. And we do prefer 17mm on a stock 914.

Don't know if it's possible, but type 1, early ghias, etc. used 17mm master cylinders and they are available still. Maybe a rebuild kit could be sourced from a parts from one of these? (Haven't really done any research yet)

[914werke]

Agree that it would be best if a rebuild kit could be offered by one of our sympathetic vendors. Because there is a difference between the 17mm and 19mm and other sizes. And we do prefer 17mm on a stock 914.

Dont know why the 19mm rebuild kits are readily available but the 17 mm kit evaporated

[mepstein]

17mm rebuild kits are a thing of the past. Im surprised 19mm still exists. I’m guessing liability issues. Where the type 1’s and early Ghia’s single or dual circuit? I know early 912’s had a single circuit 17mm MC but they are no longer available. I’m using a dual circuit 19mm on my ‘67. I recently had the front brakes go on my dually pick up. Rear brakes got me stopped just in time. I will never use a single circuit MC.

[914Sixer]

My car has a one year only 1969 911T 20mm MC used for solid rotors front and back. Really high pressure for -4 brakes. Up grading to Brembo's and -6 rears. Going to see how it works. Have NOS ATE 19mm for back up.

I find 17mm MC from time to time but VERY rare.

[914xr75]

I just purchased a fresh 17mm ATE mc at Pelican last month. You get 10% off if you've never purchased from them before.

[904svo]

Replaced the OE 17mm that came on my 74 because it was leaking out of the rear. Replaced it with the 19mm that is currently offered as a replacement.

Not happy with the increased pedal pressure required to stop the car, almost scary in a panic situation. No pedal modulation.

I would like to return to a 17mm unit but there seems to be no more out there, does anyone have a source? Is someone in the parts supply chain able to reproduce these parts reasonably?

Thanks!

Check with AA in Alanta. I belive George still has some in stock.

[bkrantz]

The 17 mm MC has a cross section area of about 227 mm2, and the 19 mm MC has about 283. That's a 25% increase in area, and pedal effort to achieve the same line pressure.

[porschetub]

My car has a one year only 1969 911T 20mm MC used for solid rotors front and back. Really high pressure for -4 brakes. Up grading to Brembo's and -6 rears. Going to see how it works. Have NOS ATE 19mm for back up.

I find 17mm MC from time to time but VERY rare.

running 19mm with Brembo 4 pots front and rear off 951 ,found it stops great for non-servo system so you should be fine when you upgrade.

[bdstone914]

Getting ready to install a 23mm MC, recommended by PMB. BMW 320i up front 914/6 rear calipers.

That sounds like too much master.
The 914-6 M calipers used the same size pistons as the 320i and used a 19mm.

[Jack Standz]

I just purchased a fresh 17mm ATE mc at Pelican last month. You get 10% off if you've never purchased from them before.

Skeptic here. Don't doubt that you are sincere, but maybe mistaken.

Can you prove that you bought a 17mm master cylinder?

Pelican has the 19mm in stock (does not show any 17mm ones) last time I checked and so does Rock Auto. 17mm have been unavailable for years and years.

[Jack Standz]

17mm rebuild kits are a thing of the past. Im surprised 19mm still exists. I’m guessing liability issues. Where the type 1’s and early Ghia’s single or dual circuit? I know early 912’s had a single circuit 17mm MC but they are no longer available. I’m using a dual circuit 19mm on my ‘67. I recently had the front brakes go on my dually pick up. Rear brakes got me stopped just in time. I will never use a single circuit MC.

Yes, do believe these were/are single circuit. But, maybe the seals in a type 1 rebuild kit fit? (Possibly requiring 2 kits to rebuild your 914 master cylinder? Don't know. Haven't done any research yet.)

[bdstone914]

Replaced the OE 17mm that came on my 74 because it was leaking out of the rear. Replaced it with the 19mm that is currently offered as a replacement.

Not happy with the increased pedal pressure required to stop the car, almost scary in a panic situation. No pedal modulation.

I would like to return to a 17mm unit but there seems to be no more out there, does anyone have a source? Is someone in the parts supply chain able to reproduce these parts reasonably?

Thanks!

It should not be that hard to stop with a 19mm. What pafs are you using?
Do you have a used 17mm master? Sometimes rebuild kits pop up. The seals are a common hydraulic style seal. I have never tried to source them. I have had a couple NOS 17mm masters that I have sold.

[Artfrombama]

Replaced the OE 17mm that came on my 74 because it was leaking out of the rear. Replaced it with the 19mm that is currently offered as a replacement.

Not happy with the increased pedal pressure required to stop the car, almost scary in a panic situation. No pedal modulation.

I would like to return to a 17mm unit but there seems to be no more out there, does anyone have a source? Is someone in the parts supply chain able to reproduce these parts reasonably?

Thanks!

It should not be that hard to stop with a 19mm. What pafs are you using?
Do you have a used 17mm master? Sometimes rebuild kits pop up. The seals are a common hydraulic style seal. I have never tried to source them. I have had a couple NOS 17mm masters that I have sold.

When I replaced the old master with a new URO 19mm I immediately noticed a difference in the pedal feel and the force required to brake. I still have the previous MC, it was still working correctly but was leaking from the rear.
I have no clue to the pads but they were new when I bought the car. New Porterfield R4S pads are in the near future.

[930cabman]

somebody has the technology to fabricate these (IMG:style_emoticons/default/idea.gif)