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Hi Guys,

Got a question. I'm building a RB25/30 (Neo) and my builder is wanting to not run restrictors in the block and have as much oil all around as possible. Now I will be running a ASR comp sump and N1 oil pump with billet gears and thought this would be sufficient. In his eyes the pump is shit and won't flow enough oil and he wants to add an additional exterior pump, still wet sump, which I really don't think is necessary. Mainly because I don't want to spend the $$$$ where it may not be required.

So my question is will the pump be sufficient to run without the recommended restrictors? He is wanting me to run near on 8 bar of pressure all the time which is huge! This car will be street driven, but will see track events through the year.

Gear I am running is -

CP pistons 8.5:1 (20thou over)

Spool Rods

ACL bearings

TRUST 1.2mm Head Gasket

ROSS balancer

ASR Sump

N1 Oil Pump

N1 Water Pump

Tomei Poncams

Plazmaman Plenum

GT35 Turbo w .82 rear

Oil Cooler so and so forth

Looking to run between 20 - 25psi and 450 - 500hp

So what do you guys think? Is he going over the top or what do you see wrong with what he is doing, ie. not restricting oil to the head. Also restricting oil to the head, is this purely due to too much oil being present or any other reason. He seems to think that I'm sorta robbing the head to keep oil down the bottom end to save bearings, whereas I thought it was purely because you end up flooding the head.

Cheers

What happens when you flood the head with oil is that there is now a lack of oil down below and you end up with starvation related bearing issues.

Why recreate the wheel? OEM pumps and restrictors are proven to work..

Oh and an N1 pump flows more than enough, hell you even have to use restrictors with an RB30E pump when running a twincam head.

Yeah what he's saying is that I'm robbing Peter to pay Paul by limiting oil to the head in order to feed the bearings down low. Now he wants to keep the head well lubricated and the bearings too.......... Which is why he's saying get another pump..

This guy builds drag engines which so far have lasted 7 - 8 years and counting so he wants this thing to last forever and wants to have everything right. But I'm not trying to run 1500hp like he is haha. I need some convincing that all this extra stuff is going to be worth it.

lol two oil pumps for a RB?

Go somewhere else dude. The guy is on crack and wasting your money.

N1 pump is fine, you need restrictors and enlarged oil returns - End of story.

You rob Paul to pay Peter with his recommendation (ie, backwards).

What happens with warranty if you do follow his advice, After the breather blow their load every time you rev it, then the head will have to come off. You dont restrict the head to increase pressure to the bottom end, you do it because there is too much flow to the head standard.

Can I guess that he (the engine builder) builds a lot of small block chevs and that's about it. I would really like to know what he wants to achieve with 8 bar of oil pressure and flooding the top end with oil.

Like the others have said find someone else

Take it to someone with a shop full of RBs, and a driveway full of RB powered vehicles. Who drives an RB powered vehicle. Bring him a holden 253 or falcon 6.I consider someone who does a lot of VL turbos the 'minimum standard".What is the volume of your sump? if it is large 8-9 L ?May compensate for the lack of oil restriction. If your billet gears are reimax (are you sure they are?) they may well NOT empty a special sump. It seems more like the Nitto, Tomei, Jun pumps that are more super high pressure and flow. Perhaps the need for some/all of the possible "oil control" mods are exaggerated.

A link stating N1 is not all that high flowing...

http://webbersrbguid...nical&Itemid=22

Edited by WHITE gtt

Yeah what he's saying is that I'm robbing Peter to pay Paul by limiting oil to the head in order to feed the bearings down low. Now he wants to keep the head well lubricated and the bearings too.......... Which is why he's saying get another pump..

This guy builds drag engines which so far have lasted 7 - 8 years and counting so he wants this thing to last forever and wants to have everything right. But I'm not trying to run 1500hp like he is haha. I need some convincing that all this extra stuff is going to be worth it.

Does he mean twin pumps? Then LOL. If he means he wants you to get a NITTO tomei, JUN greddy or nismo instead of your N1, he may be appropriately cautious. Every time a Read an RB oil control thread there are differences of opinion, but nearly every established builder runs restrictors with a high flow pump.I believe the neo is a solid head that doesn't need that much oil.

Edited by WHITE gtt

Take it to someone with a shop full of RBs, and a driveway full of RB powered vehicles. Who drives an RB powered vehicle. Bring him a holden 253 or falcon 6.I consider someone who does a lot of VL turbos the 'minimum standard".What is the volume of your sump? if it is large 8-9 L ?May compensate for the lack of oil restriction. If your billet gears are reimax (are you sure they are?) they may well NOT empty a special sump. It seems more like the Nitto, Tomei, Jun pumps that are more super high pressure and flow. Perhaps the need for some/all of the possible "oil control" mods are exaggerated.

A link stating N1 is not all that high flowing...

http://webbersrbguid...nical&Itemid=22

You can still empty a standard sump with even an RB30E pump if you have no restrictors.

It's just a simple case of he has limited knowledge on the subject.

N1 with billet gears, and run restrictors as per the guide on here. Just pull rank on him and tell him how it's going to be, it's your engine.

If there is any debate about warranty just walk now, complete the rest of the work elsewhere.

Thanks for the advice guys. I'm going to go see him tomorrow and let him know I don't want to do it, if he has a problem with it or won't warranty the engine I'll walk. They're really good engine builders but I think he's just taking it too extreme for what I want to do with it.

seriously all that set-up is going to do is fill your head with oil. it won't be able to return to the sump quick enough. I hope at the minimum he's ported/enlarge the oil returns or it'll be even worse. there's nothing wrong with an N1 pump with good gears in it.

Thanks for the advice guys. I'm going to go see him tomorrow and let him know I don't want to do it, if he has a problem with it or won't warranty the engine I'll walk. They're really good engine builders but I think he's just taking it too extreme for what I want to do with it.

They may good at building v8 drag engines but it sounds like they know nothing about building RB's. Just the sheer mention of NO restrictors and a bigger oil pump would make me RUN in the other direction.

Just take your bits to Southside and be done with it.

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