RB Reimax Water Pumps - High Flow Designs - Anyone used them?

[The Mafia]

https://www.rhdjapan.com/reimax-high-flow-water-pump-bnr32-bcnr33-bnr34-wgnc34.html

 

As you can see below, they offer significant flow over the OEM or N1 pumps. One thing that does concern me is the amount of blades. At higher RPM they might end up being a restriction as the general consensus is that you reduce the amount of blades at higher RPM to leave room for flow. 

Having 8 blades would help flow at lower RPM for example idle RPMs. 

It has the back plate design that is mean to stop cavitation too. 

Has anyone used these and can give some feedback? Thanks in advance.

 

Brand: Reimax
Product: High Flow Water Pump - BNR32 BCNR33 BNR34 WGNC34
Part Num: 21010-AAN01

SPECIFICATIONS:
Outer diameter (mm):
- OEM: 64
- N1: 70
- Reimax: 70
Blades:
- OEM: 8
- N1: 6
- Reimax: 8
Shroud:
- OEM: None
- N1: Included
- Reimax: Included
Volume (L/min):
- OEM: 160
- N1: 192
- Reimax: 221

[Duncan]

Firstly, no I have no direct experience with these water pumps.

Having said that for track/race use with sustained RPM, I would never be looking for more blades and more flow. Consider a street car probably has 1500rpm average and a race car 5000rpm+ average

I run the N1 pump with greddy oversize pulley and water temps are good, even on long runs on hot days.

[Dose Pipe Sutututu]

Jono, why not run an EWP and PWM  

Get exactly the cooling you require. Then you could even just delete the thermostat!

[The Mafia]

I want to go electric on the race car, but I want to beef up the BNR34 with something a bit better. It's just a streeter with 550-600awhp. I don't boost it that much at all. 

Up here in the tropics it gets very hot and it's a struggle to keep it under control. 

Figured a larger pump and some better fans should help the situation. 

[GTSBoy]

Just need a bigger rad core.

[The Mafia]

I've got a larger PWR core and it is no better than the stock rad. Pretty disapointed in it. 

Seems to be an airflow issue though. At 100kmph I can see temps as low as 7x degrees, even lower in winter. (Thermostat is a low temp nismo). But at idle, they get up there. 

Tried the stock fan, a GKtech fan, and a Spal3000. The spal 3000 is the only way to keep it under control.

[Duncan]

Yeah an at idle problem might benefit from more water flow, but as you mentioned fan airflow is the place to start followed by radiator volume and radiator air flow (shroud on fan and sealing air leakage around the rad)

[r32-25t]

The factory pumps work and have been used in cars that make 3-4 times your 500hp goal. if it’s not broken, don’t fix it 

[Dose Pipe Sutututu]

On 09/11/2021 at 12:49 PM, The Mafia said:

I've got a larger PWR core and it is no better than the stock rad. Pretty disapointed in it. 

Interesting, with my PWR core I could do 10 hot laps at Wakefield at the water temp wouldn't move (mind you I was runing a 25 row oil cooler).

With a Chyna eBay one, 5 hot laps and water would go over 100 - however different use case as the car wasn't idling in traffic.

[Predator1]

I looked at those for my build but didnt steered away. I figured that irrespective how much a wp flows, it really depends on how effecient the radiator/shroud combo is.

Not to derail the topic, but I personally ran the GKTech fan in my rb30, and it was utter SHIT. Swapped it with the stock clutch fan and all my water temp issues went away.

[r32-25t]

That has been the common theme with the gk tech fans,

[joshuaho96]

On 11/8/2021 at 4:49 PM, Dose Pipe Sutututu said:

Jono, why not run an EWP and PWM  

Get exactly the cooling you require. Then you could even just delete the thermostat!

Electric water pumps still call for a thermostat don't they? I remember reading in the SAE journal papers on the 2ZR-FXE about their implementation of the EWP and that engine still has a thermostat and all that fun stuff.

[The Mafia]

On 10/11/2021 at 10:00 AM, Predator1 said:

I looked at those for my build but didnt steered away. I figured that irrespective how much a wp flows, it really depends on how effecient the radiator/shroud combo is.

Not to derail the topic, but I personally ran the GKTech fan in my rb30, and it was utter SHIT. Swapped it with the stock clutch fan and all my water temp issues went away.

haha yeah I have learned this one. 

I still have the stock shroud and stock fan. It gets very hot and humid up here in the north. 

[GTSBoy]

Got an air plate between the grille and the top of the rad support?

Got sealing around the edges and bottoms of the rad and intercooler? Effort put into forcing all the air to go through those cores instead of allowing paths around them can be very well spent. Seal up the gaps to the undertray, etc etc, down the sides. Just use sticky backed Bunnings foam for a first pass test to see if you gain anything and if it's worth putting more effort in with sheet metal. I've just used corflute for some of this. Cheap, light, painted black you'd not know that it wasn't factory plastic.

[The Mafia]

On 10/11/2021 at 3:11 PM, GTSBoy said:

Got an air plate between the grille and the top of the rad support?

Got sealing around the edges and bottoms of the rad and intercooler? Effort put into forcing all the air to go through those cores instead of allowing paths around them can be very well spent. Seal up the gaps to the undertray, etc etc, down the sides. Just use sticky backed Bunnings foam for a first pass test to see if you gain anything and if it's worth putting more effort in with sheet metal. I've just used corflute for some of this. Cheap, light, painted black you'd not know that it wasn't factory plastic.

Hey mate! 

I sure do already. Foam etc. Plate on the top of the rad support etc. 

Do you think this tropics up here is partially to blame? 30+ degree heat and 90% humidty some days. It's so shit. 

[GTSBoy]

On 11/10/2021 at 3:43 PM, The Mafia said:

Do you think this tropics up here is partially to blame? 30+ degree heat and 90% humidty some days. It's so shit.

Not really. Humidity doesn't really enter into the equation for a car. The radiator works about the same regardless. Humidity is really only an issue when you use evaporative cooling (ie, your sweat).

30+ is not hot. Summer down here is 35-45. In 35° heat my car is fine. It's typically fine in 40° heat - although the oil temperature is certainly rising by the end of a 40 minute drive home after work. 45°C is also fine, just the oil gets hot earlier. All of this is with AC on (OK, well, except for the 35° case, because who needs AC at that temperature?). But I'll happily drive with the window down at 45° with no AC, and the car will keep going forever like that.

If you're suffering at 30ish, try it without the AC. I'm assuming you're using AC because it's humid and you don't want to be sticky. Just try it, see what the car shows.

Also, what is the state of the fan clutch? Does it lock up reasonably when it's hot, or does it continue to spin quite freely? If it's pretty loose, that could be your culprit. They usually fail towards lockup rather than sloppy, but anything is possible.

[The Mafia]

On 10/11/2021 at 3:23 PM, GTSBoy said:

Not really. Humidity doesn't really enter into the equation for a car. The radiator works about the same regardless. Humidity is really only an issue when you use evaporative cooling (ie, your sweat).

30+ is not hot. Summer down here is 35-45. In 35° heat my car is fine. It's typically fine in 40° heat - although the oil temperature is certainly rising by the end of a 40 minute drive home after work. 45°C is also fine, just the oil gets hot earlier. All of this is with AC on (OK, well, except for the 35° case, because who needs AC at that temperature?). But I'll happily drive with the window down at 45° with no AC, and the car will keep going forever like that.

If you're suffering at 30ish, try it without the AC. I'm assuming you're using AC because it's humid and you don't want to be sticky. Just try it, see what the car shows.

Also, what is the state of the fan clutch? Does it lock up reasonably when it's hot, or does it continue to spin quite freely? If it's pretty loose, that could be your culprit. They usually fail towards lockup rather than sloppy, but anything is possible.

Hey mate, anwers to your questions and suggestions. 

What makes me think it is an airflow issue is that when I turn the AC off but force the fan on it helps. 

The clutch is brand new and it's locking up quite well. Definitely no issue there. 

[Dose Pipe Sutututu]

On 10/11/2021 at 11:03 AM, r32-25t said:

That has been the common theme with the gk tech fans,

Yep, all junk

A few Silvias I tuned had overheating issues, popped the OEM fan back on and guess what? Went away!

[Predator1]

You could stick the AC fan on a switch, and flick it on when in traffic etc. I've upgraded my AC fan to something bigger, and I have it come with the AC as well as when ECT goes over 96(Only in crawling traffic)

[Dose Pipe Sutututu]

On 11/11/2021 at 9:56 AM, Predator1 said:

You could stick the AC fan on a switch, and flick it on when in traffic etc. I've upgraded my AC fan to something bigger, and I have it come with the AC as well as when ECT goes over 96(Only in crawling traffic)

Or wire it to an ECU output and trigger it when it hits a particular temp.

A bit more elegant than flicking a switch