To N1 or not to N1?

[m_melen]

Well I'm undecided about what kind of oil pump to use on my forged RB20DET
I've heard the N1 is a great upgrade, but is it a direct fit replacement or do you have to mess with the crank?
What's so special about the N1 oil pump? Is it a must for higher hp RB20s?
Thanks for any input guys!

[Daryl @ RightDrive]

The N1 pump is a R33/34 RB26 oil pump. It's basically a stock pump geared for higher rpms. It is in the same class as the factory pump. It is not in the same class as aftermarket pumps such as Tomei, HKS, Nismo or Jun. They are a completely different class of their own.

[Skym]

I think N1 oilpump has more pressure. You'll need to buy Tomei oil restrictor (stops too much oil getting pumped into head at high rpm's) for RB20DET (I think bigger diameter when compared to RB26DETT oil restrictor that is designed to work with solid cams) if you use N1 oilpump. N1 oilpump suits a engine with bigger air to oil engine oilcooler core, like what the N1 engines have.

N1 water pump has less cavitation (spaced the blades out more), so doesn't produce as much bubbles at higher rpm's which can make cooling system not function properly and engine overheats. Most racecars have a air separation bottle (including RB20DET racecars) to remove these air bubbles. D1 spec, Sard, ARC, etc sell air separation bottles. From what I understand ARC air separation bottle is the one to get, as it has a piece that intercepts bubbles before it gets sent into radiator (top radiator hose).

Be aware, you should only use a air separation bottle when engine has a metal headgasket, as it pressurises the cooling system beyond factory specs with a higher pressure radiator cap.

[actionbstard]

wow skym you really got the hang of it.Awsome job man.lol.
Its call air removal tank.arc is a great choice.

[Skym]

There are different names for the same bottle. Air separation from coolant is what it does, by I think was swirling coolant inside round bottle (some bottles from tuners are square). So I know it as a air separation bottle. Also the bottle shift's the high point to above radiator, engine, as bubbles rise to the highest point, which is the bottle.

[m_melen]

so is anybody running this air separation tank?

[ARC240]

I went N1 oil pump, I've seen countless drift cars including a built RB26/30-powered S13 drift Silvia using an N1 oil pump. If it's good enough for a car like that, I'm not scared. Good upgrade. For water pump, I didn't bother with an N1, it's a waste if you're mainly driving the car on the street, even if you occasionally track the car, the stock pump will do just fine, you only get the benefit of an N1 when the car is consistently at high RPM situations (ie. on a track) or if you're building some really significant power numbers and need the extra cooling. I remember somewhere that N1 pumps had a fitment issue when installed on RB20's, could be a figment of my imagination. Anyone care to chime in?

[Skym]

N1 oilpump doesn't take higher rpm's like 8500rpm in one case on a RB26 very well. You need to keep the factory rev limiters and peak power rpm.

JUN, etc oilpumps are better in which you can raise the revlimit. But full drysump / external wetsump oilpump setup is the best solution for higher reving RB engines.

Reving usually wears out an engine out quicker due to excessive inertial load on bottomend that can snap stock or aftermarket H beam conrods and send conrods through the side of shortblock. Most tuners use lower revs 5500-6400 rpm and more boost instead of more revs. More revs suck in more air and when mixed with fuel, produces the hp. An example is N/A F1 engines.

If car idles around for long periods like in traffic jams, stock waterpump is better.

Here's a diagram of what the airseparation bottle does -

http://www.trust-power.com/04cooling/breather_tank.html

Nearly every racecar and road/track driven GTR's I know of have a airseparation bottle.

[actionbstard]

Can't remember who made upgrade gears for the oil pump.Thats why some run a N1.I asure you the rb26 don't like N1 stock oil pumps.Oil is another important issue don't cheap out on that part.Of course a damper such as ATI and metal jacket will help in high revs.
For me I will go the way I always go.
Upgrade Damper.ATi or Metal Jacket
Oil pump.JUN or Tomei (Dry Sump set up)
main studs.Tomei or ARP
race bearings.ACL
ruds.Manley or Eagle
and clutch.OS Giken
Pistons.same sht.Tomei,Jun,HKS,brands that actually test them.

Theres alot to cover on making a high reving RB.This is for the Block.
Head work?well that to much for my typing skills.

[Dragon Humper]

Don't let anyone tell you that an N1 oil pump isn't much better than stock. It's a great upgrade for a stock/budget/sub 700hp build. The internal differences goes much farther than just a stronger spring. The gears are beefier, there are less teeth (helps with cavitation), the oil passages are larger/more direct and the cover has one extra bolt to keep the gears from walking in the housing. They have been run at 8000rpm for LONG races in the past and will take the odd excursion to 8500 or even 9000rpm.

For the price point they are steal. For capibility I would put them right in the middle of the stocker and a $1200 Jun, Tomei or Nismo. All for about $300 if you shop around (sometimes less).



Jon.

[Skym]

I think Renik is the company in Japan that sells the upgraded gears for stock oilpump.

N1 oilpump failure -

http://forums.gtrcanada.com/showthread.php?t=25385

[actionbstard]

maybe if you mod the gears and run a better damper,put still not even close to Nismo,Jun,Greddy or tomei.To me Tomei and jun are the best.But we tend to rev the sht out of our engines.Belive me when it comes to oil pumps.Go for the best.
I can't count how many belived that sht about N1s but sures not funny.Do you have any idea how much is at risk?
I will run a tomei or jun nothing else.If I don't have the money for Drysump set up.
accusump and a N1 with moded gears and don't even think about runing revs above 8k.
7.5 is still lots of fun.If you still want to run a N1 find a turbo set up that will spool in the 3k rpms our less.Some cams will help spool.
I sure hope not to see you in a bad spot just because you went cheap on a oil pump.
Do a research and at the end its your money.All we can do is try to help.It you that decides what to do.
Can't belive this guy comparing N1 with Tomei????That just plain fcked up man.

[Dragon Humper]

.Can't belive this guy comparing N1 with Tomei????That just plain fcked up man.

Who, me?


You want to run a $1200 Jun in an RB20 when the tranny can only take 350hp anyway........OK, sounds like money well spent.




Jon.

[sexonwheels]

Can't belive this guy comparing N1 with Tomei????That just plain fcked up man.

No need to freak out. He said it was somewhere in the middle of the stock oil pumps and the top performance oil pumps.

+1 for dragonhumper.

There's no need for over kill and buy a $1200 oil pump when your only making a few hundred hp. N1 is a decent upgrade.

[RABBIT]

can some one run down a price list for all the pumps , ie , OEM R32 , N1 , Nismo , Jun , Tomie , Renik and any others./