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Hey all, was under the impression that the N1 water pump is a high volume water pump compared to the standard r33 gtr water pump, though, the N1 water pump has less fins than the factory pump.

N1 has 6.

Standard has 9 i think.

Therefore you would assume the more fins the better??

Can somone shed some light on this situation please?

Thanks guys!

the n1 is less volume due to the use of sustained higher rpm on high output engines or track use in general. The stock pump will flow the water around too quickly when using constant high rpm.

and the plate thats at the back is to reduce/stop cavatition also.

Hard decision to make when you are trying to make the engine reliable for track use, so you don't want it cavitating at high revs. But in reality it will probably spend most of it's life driving on the streets and depending on where you live, stop/start traffic, so you need a pump that flows well at idle/low revs

I'd reckon almost any car should use std not n1 pumps.

There are very few cars, even with track use, that do more than 3-5 laps flat out at a time.

Full on race car like my production car has one and it helps keep temps down (still too high), but that is up to 1 hr enduro at an average of 5-6000rpm.

yep I run an oversize pulley on mine as well as an n1 pump. and a flow restrictor in the hose. and a larger radiator with shroud. and distilled water with redline water wetter. depends how serious the cooling need is I guess.

One big issue with oversize water pump pulley is it will foul on the harmonic balancer which you need to cut back for clearance.

but the n1 pump isn't really "more efficient", there's nothing actually wrong with the standard pump in normal and spirited driving use. Its just when it's running 3 times faster all the time things get silly.

yep I run an oversize pulley on mine as well as an n1 pump. and a flow restrictor in the hose. and a larger radiator with shroud. and distilled water with redline water wetter. depends how serious the cooling need is I guess.

One big issue with oversize water pump pulley is it will foul on the harmonic balancer which you need to cut back for clearance.

but the n1 pump isn't really "more efficient", there's nothing actually wrong with the standard pump in normal and spirited driving use. Its just when it's running 3 times faster all the time things get silly.

I was referring more to the standard rb26 pump, it has more fins and flows more so by putting a larger pulley on you would simply slow the flow down slightly which is better for higher rpm driving. Probably in the middle of the two...

i ran an n1 water pump on my fairly modified rb26 in a stagea using the stock radiator that it come with (used to be rb25) and it was perfect in traffic and never ever ever got warm, i went in Motorvation local carshow and sat idle in traffic the supercruise with outside temps of 35 degrees + and it was perfect and other cars were cooking lol. I run an ATI 1000hp balancer which is very small compared to the stock one so it would be spinning even slower and still no issue.

i ran an n1 water pump on my fairly modified rb26 in a stagea using the stock radiator that it come with (used to be rb25) and it was perfect in traffic and never ever ever got warm, i went in Motorvation local carshow and sat idle in traffic the supercruise with outside temps of 35 degrees + and it was perfect and other cars were cooking lol. I run an ATI 1000hp balancer which is very small compared to the stock one so it would be spinning even slower and still no issue.

remmeber the 100hp ati balancer comes with a water pump pulley :P

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