Matt Sheppard

How is it different from a 951/944 waterpump?

Lemming

I cannot directly answer your question. I will tell you that two of the three 968 engines that I bought came with 2.5L water pumps. My 968 daily driver also had a 2.5L pump installed.

SpeedBump

probably more expensive than the 944.

Matt Sheppard

I dont get it. . .

There must be some difference. Wormhole wants the one I have and I am trying to figure out why a regular 951 part is any different. What does he know that you/I don't?

RajDatta

Usually, 968 waterpumps say 2.7l on them. This is to differentiate them, 2.7l, S2 and 968's all share the same block type.
Raj

FRporscheman

The impeller on the 2.7/3.0 is larger... well it's supposed to be larger. The impeller on the 2.5 is smaller. So you can use a 2.5 on a 2.7/3.0 block, but if you use a 2.7/3.0 pump on a 2.5 block it will barely rub on the machined ridge on the block.

Also, 2.5 cores are a dime a dozen while 3.0 cores have a little value (hard to find and most S2/968 owners need a true 2.7 core to exchange for a rebuilt one, and their car has a 2.5 pump bolted on...).

rdhayward

To clarify, are you saying that a 2.5 water pump can be used on a 968? Would be nice to find a cheaper alternative.

Lemming

I have used a 2.5 on my daily driver 968 with no apparent ill effects, YMMV.

Matt Sheppard

Interesting stuff - thanks Arash

FRporscheman

Yes, in my experience a 2.5L waterpump will work perfectly fine on a 3.0L 968 engine. When I bought my blue car it had a 2.5 pump on it and it always ran fine, and held good temps, and I recently changed it to the 3.0 pump when I did the belts. It does run a few degrees cooler now. Sure, it could be the new thermostat, but it could also be the bigger WP impeller.