Water pump pulley

[shane@mbtech]

Now I'm even more confused. The reverse of that you say...

So is that slow speed = warm, fast speed =hot

Or full speed = cool, low speed = cold.

To my mind there must be an optimum speed of coolant flow for a given size of radiator. Surely too slow will mean the coolant is cooled A LOT in the radiator, at the detriment of the coolant left in the engine which will peak much higher.
Too fast and it won't be cooled sufficiently by the radiator before being pushed back into the engine?
Where is the Gorilla when you need him???

It was more in response to shimmys quote about the time the coolant is in the radiator for.

If it's pushed through quicker then it's less likely to cool. That's why I likened it to electric shower, but opposite way round.

[uncle benz]

It was more in response to shimmys quote about the time the coolant is in the radiator for.

If it's pushed through quicker then it's less likely to cool. That's why I likened it to electric shower, but opposite way round.

Ahh, I get it now!

A bigger radiator has to be a better bet than messing with pulley sizes.

[shimmy]

It was more in response to shimmys quote about the time the coolant is in the radiator for.

If it's pushed through quicker then it's less likely to cool. That's why I likened it to electric shower, but opposite way round.

Yes, and I was saying (badly) that a bigger rad then will allow the water to cool more as it will stay in the rad longer even though it is flowing faster.

[Mike RT4]

Given how easy it is to reverse this, it should be very easy to test. Access the water temp menu so it is displayed in specific figures and carry out some measurements at a track day (noting ambient temp / barometric pressure changes through-out the day) and then repeat with the other pulley (even better if you can do this on the same day).

[adem.csl]

Alex was talking about circumference Adem, the distance around the edge. You'd quote diameter which is straight across the pulley.

Iirc circumference = 2x pie x diameter/2 = 2 x 3.142 x 12/2= 37.69 (I'm exhausted now)

Wicked cool im a monkey not a mathematician lol!
Thanks shimmy

[shimmy]

Wicked cool im a monkey not a mathematician lol!
Thanks shimmy

I had to get my daughter to explain to me first :-D

[_Nathan_]

I fitted underdrive pulleys to slow down the water pump (and alternator) and extend the life of those parts, wouldn't want either running faster!

[alexk]

I fitted underdrive pulleys to slow down the water pump (and alternator) and extend the life of those parts, wouldn't want either running faster!

Nathan is it not causing an issue to the cooling ? Slowing down the water pump ?

[_Nathan_]

Doesn't seem to be the case.

I actually wonder if the high speed of the water pump is causing cavitation at high RPM running on track?

[shimmy]

Doesn't seem to be the case.

I actually wonder if the high speed of the water pump is causing cavitation at high RPM running on track?

I had underdrive pulleys for a while, cant remember when but will check data and see if had overheating problems still with them in (def no problems at normal speeds or stopped)!!

[alexk]

Doesn't seem to be the case.

I actually wonder if the high speed of the water pump is causing cavitation at high RPM running on track?

Very interesting.

[shane@mbtech]

Doesn't seem to be the case.

I actually wonder if the high speed of the water pump is causing cavitation at high RPM running on track?

Another possible contributory factor maybe.

[alexk]

Another possible contributory factor maybe.

Very true, because as soon as you back off, the water temp drops immediately.

[shimmy]

Very true, because as soon as you back off, the water temp drops immediately.

Not convinced

My feeling is it is throttle related, not revs. I can be at full throttle but not full revs when the temps start to move

If it was water cavitation it would be caused when car runs at max revs, not max throttle/fueling

[shane@mbtech]

Not convinced

My feeling is it is throttle related, not revs. I can be at full throttle but not full revs when the temps start to move

If it was water cavitation it would be caused ephedra car runs at max revs, not max throttle/fueling

Is it that instantaneous?