Hose fitting size for a Porsche G50/3 slave cylinder?

Chet Zerlin

Supporter
Hi all,

For my RCR40: Would anyone know what the correct size fitting is for this clutch slave cylinder for a Porsche G50/3 transmission?
R95011623712EQ.jpg



The hose that Porsche sells (which costs more than the slave cylinder!) would not work since the fitting on the master cylinder side does not match the fitting on the line to the master cylinder that is supplied by RCR.

Also a source for the needed fitting/adapter ( or a source for a custom hose) would be greatly appreciated.

Thanks,
Chet
 
Also ich habe auch ein g 50/00 porsche getriebe in meiner lola und habe auch den gleichen nehmerzylinder verbaut du must den gummy schlauch kaufen und dann erst wie ich das gemacht habe zu der starren bremsleitung übergehen das geheimnis ist das volumen im schlauch brauchst du damit dein gezogene gabel schnell wieder zurück in die ausgangs position zurück geht
 

Brian Kissel

Staff member
Admin
Lifetime Supporter
So I also have a G 50/00 Porsche gearbox in my Lola and have also installed the same slave cylinder. You have to buy the rubber hose and only then switch to the rigid brake line like I did. The secret is the volume in the hose you need your pulled fork quickly returns to the starting position
 

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Chet Zerlin

Supporter
Olf59, I'm trying to understand what I am looking at in your picture. Is that the standard Porsche clutch hose with an adapter to mate it to the rigid line going to the clutch MC? If so what fitting/adapter did you use to match it to the rigid line?

I'm understanding that the size fitting needed on the Porsche clutch slave itself is a "M14x1.5 double flare". When I search for that I get "inverted flare" instead of "double flare" so I'm wondering if that the same thing?

When you say the secret is the volume in the hose are you suggesting that getting an adapter to go directly from the M14x1.5 fitting down to a -4 to mate to a standard brake/clutch line would not work since the volume in that smaller hose would not be sufficient to ensure the pulled fork returns to the starting position?

Thanks!
Chet
(Brian, thanks for posting the translation!)
 
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Hi chet genau so ist es die gabel schnappt schneller in die ausgangs position zurück weil der durchmesser im schlauch größer ist als bei einer starren leitung die kupplung schleift weniger und hält länger . es wird natürlich auch ohne den schlauch gehen (was ich davor auch mit einer stahlflex leitung angeschlossen hatte) aber dies geheimniss hat mir ein alter rennmechaniker gesagt . dann ist noch zu sagen das ich auch den gebezylinder vom porsche eingebaut habe damit das übersetzungsverhältniss stimmt bei den fittings / gewindegrößen muss man ein wenig probieren hier in germany ist das einfach zu kaufen .dann ist noch zu sagen wenn dein motor über 350 nm drehmoment hat brauchst du eine dickere kupplungsscheibe und wenn möglich von kennedy die stage 24 druckplatte sonst hast du nicht lange was von deiner kupplung
 

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Brian Kissel

Staff member
Admin
Lifetime Supporter
Hi chet that's exactly how it is, the fork snaps back into the starting position more quickly because the diameter in the hose is larger than with a rigid pipe, the coupling drags less and lasts longer. Of course it will also work without the hose (which I had previously connected with a steel flex cable) but an old racing mechanic told me this secret. Then it should be said that I also installed the master cylinder from the Porsche so that the gear ratio is correct. You have to try a little with the fittings / thread sizes. Here in Germany it is easy to buy. Then it should also be said if your engine has over 350 nm torque You need a thicker clutch disc and if possible the Stage 24 pressure plate from Kennedy otherwise you won't have any use of your clutch for long
 

Chet Zerlin

Supporter
Thanks for your reply (and a thank you to Brian and Google Translate :) )
Would you happen to know what thread/fitting is on the female side of the Porsche OEM clutch hose you used?

Chet
 
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