Alright chaps,
With the sodium filled valves currently extinct from VW i have been thinking about alternatives. Sodium filled valves are a good way of converting heat through conduction, however it wont occur until the sodium has melted and passes over both surfaces. The melting point of sodium is roughly 100*C, and my running temperature never seems to surpass 80*C. So are the sodium filled valves aimed at turbos/track cars?
Anyone comments on engine temperatures for turbos or track orientated cars?
I have found exhaust valves made by 'Intervalve' which state a Bi-metal, i am currently running a set of inlet valves from them, but will be inquiring as to which metals they are and their heat rating.
Just interested to hear of any valve alternatives..
Your coolant might not be exceeding 80'C.... but your exhaust gas temp definitely is!
Not an alternative but I believe these are the sodium filled exhaust valves for the PY engine
http://shop.volkswagen-classic-parts.de/vwcp/Polo-Derby/Polo-II-2F/Antrieb/Motor/Auslassventil.html (http://shop.volkswagen-classic-parts.de/vwcp/Polo-Derby/Polo-II-2F/Antrieb/Motor/Auslassventil.html)
Quote from: Yoof on January 13, 2014, 08:07:55 PM
Your coolant might not be exceeding 80'C.... but your exhaust gas temp definitely is!
Ay, but interested in temperatures reached by tuned/turbo's engines that will be running hotter!
Quote from: paulpolo on January 13, 2014, 08:12:01 PM
Not an alternative but I believe these are the sodium filled exhaust valves for the PY engine
http://shop.volkswagen-classic-parts.de/vwcp/Polo-Derby/Polo-II-2F/Antrieb/Motor/Auslassventil.html (http://shop.volkswagen-classic-parts.de/vwcp/Polo-Derby/Polo-II-2F/Antrieb/Motor/Auslassventil.html)
Yup, these are top dolla, I wonder if it would be more economical to go straight to the manufacturer in this case 'intervalve' and custom make a hollow sodium filled valve, with the g40 spec! I will have a chat with the local engineering company that got me a set of inlet valves last time.
Quote from: physicsfool on January 13, 2014, 08:48:08 PM
Quote from: Yoof on January 13, 2014, 08:07:55 PM
Your coolant might not be exceeding 80'C.... but your exhaust gas temp definitely is!
Ay, but interested in temperatures reached by tuned/turbo's engines that will be running hotter!
Not always- depends how much fuel is used.
£20/valve is a fair price, I doubt you'd get a low volume run any cheaper. Also you've got all the design effort, testing, validation etc. Better to stump up £80 and know they're right.
Pete