Gentlemen,
Since fitting a long fifth gear to my Renault 21T gearbox during the winter, I have been investigating my car's performance.
Generally, top gear acceleration is still pretty good, motorway driving is more comfortable because rpm has dropped by about 500 at 70mph, but overrun, because of reduced engine braking, is greater and caught me out slightly until I got used to it.
But that's not what I want to air.
At 'low' speeds in top gear (<80mph) the water temperature is rock solid at 85C. The car doesn't overheat when stationary if I switch the fans on, so I'm pretty satisfied with the cooling system.
However, at higher speeds (>100mph) the water temperature cycles continuously, working slowly up to about 95C then dropping quickly to about 70C, before slowly increasing again. Drop the speed and the temperature immediately settles down again.
Engine rpm is typically 3500 when this happens, which is less than it was before, obviously.
Any ideas, or have I just spotted something that has been going on for the last 2 years without my noticing?
Since fitting a long fifth gear to my Renault 21T gearbox during the winter, I have been investigating my car's performance.
Generally, top gear acceleration is still pretty good, motorway driving is more comfortable because rpm has dropped by about 500 at 70mph, but overrun, because of reduced engine braking, is greater and caught me out slightly until I got used to it.
But that's not what I want to air.
At 'low' speeds in top gear (<80mph) the water temperature is rock solid at 85C. The car doesn't overheat when stationary if I switch the fans on, so I'm pretty satisfied with the cooling system.
However, at higher speeds (>100mph) the water temperature cycles continuously, working slowly up to about 95C then dropping quickly to about 70C, before slowly increasing again. Drop the speed and the temperature immediately settles down again.
Engine rpm is typically 3500 when this happens, which is less than it was before, obviously.
Any ideas, or have I just spotted something that has been going on for the last 2 years without my noticing?