How much power and torque do you think is lost when the intercooler pump isn't working? Mine has been dead for probably years, I will repalce it this winter though but I was just wandering how much I had lost.

 

I would say at least 50% of the extra “oomph” the supercharger could’ve provided, IF the air had been cooled properly.

Hot air expands A LOT, and it doesn’t have nearly as much O2 as a result of the expansion, even after the compression of the supercharger.

Z

 

Not good then, I should really get it sorted out. If the car has 400hp stock I should think it's probably around 300hp I guess?

 

Just a guess, but you probably have a little more than what the non-supercharged XK8 has, whatever that number is.

Of course the XKR’s don’t have the advantage of variable cam timing. With the intercooler working properly, that doesn’t matter, but in your case, it does matter.

Z

 

Will the intercooler pump run all the time when the car is running. So so much on this XKR is still a mystery to me.

 

I believe so. You can hear it running with the key in the -on- position. Also can feel the fluid pulsating in the coolant hose going to the intercooler.

Z

 

Beyond reduction in torque, peak power and throttle response, there will also be the latent effects of thermal load.
Everything will be fine in the first few minutes when static Intercooler coolant is cold but the heat build-up will quickly alter combustion conditions. I expect engine management will adjust fuel input to compensate for spurious O2 Sensor readings. This inefficiency will cost more at the pump and increase emissions.
If you were driving hard then such heat load would normally melt Spark Plug electrodes - but ours are Iridiums and extremely robust so I wouldn't be overly concerned with that. Ultimately, there will be more demand on the engines cooling system to reject the extra heat and perhaps your electric fan is on more often....?

 

Beautiful and good to know. Thank you!!!

I'm going to have to have a look see. I would hate to learn (but might trigger a Bosch pump upgrade) that the pump isn't functioning. We'll see!
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