Pentroof NA Roadster Water Bypass Kit

Pentroof has developed the best system to bypass  your heater hose. 

In the NA6 & NA8 roadster engines, if you bypass the heater hose from the cooling watner, you can reduce the path that the coolant has to travel you can make your cooling more effective.

Rear cylinder heat temperature is stable and easy to accumulate by this, to prevent overheating while controlling the water temperature rise.  Recommended for circuit driving.

Note:  No Thermostat is supplied with this kit, only all the parts shown.


  • Hose Clamps (large and small)
  • Stainless mesh hose
  • Water bypass
  • Mesh hose adapter


Please Note:

If you do not see your part listed, or have any questions, please make an enquiry.  We are happy to answer.


This part usually ships 12 days after payment.

Product Version Price Order
Mazda - Roadster - NA6CE/NA8C - Water Bypass Kit
USD $ 223.58

Vehicle Compatibility

Mazda - Roadster - NA8C
Mazda - Roadster - NA6CE

Vehicle Compatibility

Mazda - Roadster - NA8C
Mazda - Roadster - NA6CE
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Nengun Performance
4798-455 Imazu
Nishi-ku, Fukuoka
Japan, 819-0165

Kobutsuho No.