Meziere electric water pump for racing - anyone has any experience?

[halllon]

Those of you that are/have been running Meziere water pumps, especially when racing/drifting:

 

Have you had any issues?

Does it supply enough flow? I can see that it is only rated at 20gpm.

 

We are thinking of putting one on a 2JZ drift car with rear mount radiator setup.

 

Thanks!

[Digsy]

Can you post some more details of the pump?

 

I've done a lot of work with electric water pumps (EWPs) in the OEM world. Sizing them is very difficult and engines that use them as the primary water pump usually have low backpressure coolant systems designed around the pump. With its long block and U-flow coolant layout, the 2JZ will not fall into this category.

 

Many mechanical water pumps are sized for the "hill climb / trailer tow" kind of test where you have a high amount of heat rejection into the coolant relative to the engine speed and vehicle speed (and hence water flow and airflow through the radiator). This means that a fixed speed mechanical water pump is often oversized for the peak power / max speed condition where you have maximum coolant and airflow. This is where in a road car some efficiency gains can be made by using a water pump that can offload itself.

 

At a rough guess the stock Supra pump will probably flow about 200-250 litres per minute at full chat.

 

Racing, I suspect, will be closer to the latter case, so you could possibly get away with a slightly smaller pump. Cars have raced at LeMans using twin Davies Craig pumps (max flow rate 100 litres per minute / 22gpm each). I think that's more in the ballpark.

 

However for drifting I guess you will be spending a lot of time at high revs but with not much air going through the radiator (unless you are using fans), so you want as much coolant flow as you can get. I suspect that sticking with the mechanical pump might be just as good an option as an EWP.

 

Looking at their website, I see that Meziere do much larger pumps (up to 55gpm). It would be interesting to see how that drops off with system backpressure (the max flow rate will probably be stated at zero backpresure which is an unrealistic case). In reality under all operating conditions you won't get the maximum flow out of the pump.

[halllon]

The pump seems to push about 20 gpm. I guess I will try the stock pump up front then, and a larger one in the rear of the car by the radiator outlet. We will be running a trunk mounted radiator with ducting from either underneath the car or from the roof side, using two Derale electric fans.

[Digsy]

I hate to labour the point but saying the pump flows 20gpm is meaningless unless the supplier also states at what backpressure, or supplies a flow / pressure curve. When only a flow is stated it is usually at zero backpressure, which is not what you will get when you plumb it in. The total system backpressure from a long engine with a U-flow cooling system like the 2JZ, plus the additional pipework running to the rear of the car and back will probably be pretty high. I know a bit about pumps, but I'm less hot on radiators. Can I ask what you stand to gain by running a rear mounted rad?

[Chris Wilson]

Rear mount rads are a nightmare, believe me. Only do it if you have an excellent and very compelling reason. Getting air in and out of them to the same effect as a front mount rad is REALLY hard, plus you are nailing on a lot of extra weight.