Can anyone tell me the approximate temperature reached in the combustion chamber of a 4.2 series 2 XJ6 engine?
Dear Nigel,
It will depend on engine load and rpm, amongst other factors.
At idle it may be in the order of 180’c and accelerating up and past 3000rpm it may be around 650’c.
kind regards
Marek
Hi Marek
Thank you very much!
Best regards
Nigel Boycott
Nigel,
I don’t know what you’re aiming at with your question. The figures Marek indicated seem to be common ground for most Otto engines, but seem to relate to temperatures during the compression stroke. Combustion temperatures will be around 1500 to well over 2000°C and even the exhaust gases will be around 800 to 900°C, at full load up to 1000°C. There is a reason why head gaskets and exhaust gaskets need extra protection.
Good luck
Jochen
75 XJ6L 4.2 auto (UK spec)
I use an Exhaust Gas Temperature ga. mounted in the dash of my 420. Twin carb 4.2. I can only give exhaust temperatures. Highest I have seen measured in the exhaust manifold is 1400F to 1450 under constant highway speeds. This should be about 750 - 800C but it is an exhaust reading near the head, not in the combustion chamber as you asked.
I hope I haven’t drifted too far off the basic question.
Hi Jochen
Thanks for your information it all confirms what I thought.
Best regards
Nigel
My data is based on EGT sensors which sit embedded inside the air injection ports. The tips are thus very close to the exhaust valves. Obviously there is no practical way to get inside the combustion chamber which will experience hotter temperatures.
kind regards
Marek