Solutions for performance RB problems

[cheftrd]

if only nissan had done it right in the first place eh?

 

 

They did get it right, for the most part. They didn't build the motor for 10,000 rpm and 2 bar of boost, which is how most of these mods came to be. Now the entire Intenet thinks that their 500hp RB26 is going to come apart at the seams if they don't do these "miminum" mods...

 

Here's a new one that goes along with the others: Don't forget to change the intake valves. Engineis with stock valves and heavy springs have a hard time keeping the head on the stem over 9,500 rpm... Valves love to drop into the cylinder.

 

 

Here's some RB trivia: I first did the "oil drain back" about 13 years ago, but the mod wasn't originally intended to return oil to the pan. I think some people saw it being done on very high power RB's, assumed it was an oil drain, and the ball was set rolling... Anyone got a guess, or know what the actual purpose is?

 

Hint: It promotes oil drain back. Later small-port Toyota 4AG's started getting the mod from the factory.

 

At 1g of forward acceleration, the oil in the pan will stand up at a 45* angle on the rear bulkhead. How is oil from the rear of the head moving forward to the front of the oil pan in my 8 second GT-R?

 

 

Later 32 engines have the long oil pump drive too (around the same time they went to a pull-clutch. It's not really a problem unless you're turning around 8,500 rpm. If you're turning sub-8,000, there's no reason to upgrade the stock pump, so you don't really need to be worried. If you're concerned, get a big oil pressure light. As long as you shut it down right away, the motor will be fine. There are thousands of GT-R's running around in Japan without the oil pump drive mod

[jerryb]

What ...you dont know what NICO is!!!! Arghhhhhhh!

 

Go to www.NICO.com the site for all models NISSAN.

 

While there look for my banner...http://www.BLAZT.BIZ

 

HEHEHE..sorry.......

 

consider my balls well and truly busted:icon52:

what is the NICO forum?

[Z24O]

They did get it right, for the most part. They didn't build the motor for 10,000 rpm and 2 bar of boost, which is how most of these mods came to be. Now the entire Intenet thinks that their 500hp RB26 is going to come apart at the seams if they don't do these "miminum" mods...

 

Here's a new one that goes along with the others: Don't forget to change the intake valves. Engineis with stock valves and heavy springs have a hard time keeping the head on the stem over 9,500 rpm... Valves love to drop into the cylinder.

 

 

Here's some RB trivia: I first did the "oil drain back" about 13 years ago, but the mod wasn't originally intended to return oil to the pan. I think some people saw it being done on very high power RB's, assumed it was an oil drain, and the ball was set rolling... Anyone got a guess, or know what the actual purpose is?

 

Hint: It promotes oil drain back. Later small-port Toyota 4AG's started getting the mod from the factory.

 

At 1g of forward acceleration, the oil in the pan will stand up at a 45* angle on the rear bulkhead. How is oil from the rear of the head moving forward to the front of the oil pan in my 8 second GT-R?

 

 

Later 32 engines have the long oil pump drive too (around the same time they went to a pull-clutch. It's not really a problem unless you're turning around 8,500 rpm. If you're turning sub-8,000, there's no reason to upgrade the stock pump, so you don't really need to be worried. If you're concerned, get a big oil pressure light. As long as you shut it down right away, the motor will be fine. There are thousands of GT-R's running around in Japan without the oil pump drive mod

 

not sure i agree with all of the above,however i did find it a bit confusing,so maybe i got the wrong end of the stick

 

there are plenty of guys in Oz with short snout drives that have cracked standard rb26 oil pump drives with disastrous and expensive consequences,and these aren't track/drag cars either (maybe it's our long straight roads,do you guys in japan ever find a road that you can actually open an RB26 up on:rolleyesg,maybe that's why they last so long)

 

with regard to G forces,i don't know about you guys but 11 seconds of pulling G's is about as much as i can take on one change of underwear

by all means get a properly baffled sump.....it all helps

 

i have personally seen many rb26 head components damaged by restricting the oil flowing to the head,the drain seems to make more sense and there have been no adverse effects with this mod to date

 

at the end of the day,these mods are a bit like insurance....may never need it,but may regret not having it at some stage

in the scheme of the cost and inconvenience of a rebuild i'll let individuals decide.....me i can save $100 elsewhere

 

for those guys who ordered and paid,i will be sending them out tomorrow

[cheftrd]

not sure i agree with all of the above,however i did find it a bit confusing,so maybe i got the wrong end of the stick

 

there are plenty of guys in Oz with short snout drives that have cracked standard rb26 oil pump drives with disastrous and expensive consequences,and these aren't track/drag cars either (maybe it's our long straight roads,do you guys in japan ever find a road that you can actually open an RB26 up on:rolleyesg,maybe that's why they last so long)

 

with regard to G forces,i don't know about you guys but 11 seconds of pulling G's is about as much as i can take on one change of underwear

by all means get a properly baffled sump.....it all helps

 

i have personally seen many rb26 head components damaged by restricting the oil flowing to the head,the drain seems to make more sense and there have been no adverse effects with this mod to date

 

at the end of the day,these mods are a bit like insurance....may never need it,but may regret not having it at some stage

in the scheme of the cost and inconvenience of a rebuild i'll let individuals decide.....me i can save $100 elsewhere

 

for those guys who ordered and paid,i will be sending them out tomorrow

 

 

My GT-R has buried the 320km/hr speedo, so they must be straight enough... Have you seriously not heard of the Wangan Expressway? I thought Japan was the leader in top-speed illegal street racing. So why the sarcasm?

 

Anyway, sure lots of guys have broken the pumps. Lots of my customers have broken them, too (I believe I posted pics here years ago...). To date, there's been exactly one catastrophic failure...because the guy drove it home with the light on and no pressure. The others were shut down right away and suffered zero damage. I broke one at 9,000rpm and tore the engine down only to find zero bearing damage. Like I said, the only time it seems to happen is when you start getting into the bigger revs. If you have an RB26 that's only making around 400-500hp and the max revs are around stock, you won't have a problem. If you have the motor apart, by all means modify it, but to tear a motor completely apart just to do this mod when you're keeping it close to stock is foolish. A bright warning light is all you need. You stated that all 32's have the short drive. This is false. Only the early 32's have the short drive. The crank changed when they went to the pull clutch ( I don't remember the year).

 

On G forces... I'm talking about accelerating forces. My GT-R has gone 8.8" in the quarter. At one G of forward acceleration, the oil will stand up at 45 degrees in the rear of the sump. I'm not talking about baffeling, I'm talking about oil defying the laws of physics. Tell me how oil is returning to the sump down the long -16 hose I have running from the back of the head to the front of the pan. Plain and simple, when It's on the gas, oil doesn't move forward. In fact, if your hose is at the bottom-rear of the GT-R sump, you have a nice exit for oil to leave the sump. Of course it would drain straight down into a Z's rear sump, but it was done waaay before that in front sump pans. So what gives? I originally started doing this mod around 1995. I didn't say it wasn't necessary in big power engines, I said it's not for oil return. It's for blow-by. It facilitates oil return.

 

See, when you have an RB26 that turns 10,000rpm at 30 pounds of boost, there's a tremendous amount of blow-by. It's inevitable. Now, if you have all this blow-by going up the oil returns on the left side of the engine, into the head, and out the vlave covers, where is the oil returning? It's not. Natural crank windage wants to pull down on the left side of the engine. It also wants to push up on the right side of the engine. That's why the drains are on the right in the RB26 and most engines that the crank rotates in that direction. When you pop that hole on in the pan on the right side and run a large hose to the back of the head, you're creating a natural path for the blow-by up to the head. This in turn will create a sort of suction on the vents on the right side, alowing oil to more easily return to the sump. It's unnecessary on 99.9% of the motors on the road. The super Taikyu engines don't use it. The HKS Zero R doesn't use it. The R34 Nismo Z tune doesn't use it... Lap after lap on the Nurburg Ring with no problems. Saurus is one of the top RB26 drag engine builders in the world. I've had a few of their 700+ hp engines roll through my shop and none of them had the oil return mod. None of 'em had oil pressure problems, either. It's a mod that's required for big boost, big rpm engines. People have been led to believe that the stock oil returns are inadequate, and if you don't do something about it, your motor will break, and that's just false. I've done countless 500hp-ish RB26's that have never, ever had this problem. Once again... Not saying don't do it. Just that most people dont need it, but have been duped into believing they'll have engine woes if they don't.

 

I have never installed an oil restrictor in the RB26. I have never had a problem with oil pressure due to lack of oil in the pan because it's in the head. Something I don't understand, if you've "personally seen many rb26 head components damaged by restricting the oil flowing to the head", why would you even be selling 'em?

 

 

 

Since this seems to be the new classifieds section, keep an eye out in the real classifieds, as I'm going to be parting out my R in the comming days and weeks. Everything goes except the body, which is an original Nismo R32.

[Careless]

So if I ran an RB26 head on my RB30 with an oil drain mod, total seal gapless rings so that there is no blow-by (it's N/A, do I really need it?!) no restrictor, and an increased volume / pressure oil pump... could there be any side affects, and on which side of the sum should it return?

 

EDIT: is this what we're looking at here (except the feed line for the blow-by release would be above the oil level, and not below it)

 

[Z24O]

so there you have it guys ^^^^

proving everyone is entitled to an opinion.......but only you can make up your own mind

and that is precisely why i have the oil restrictors available,i personally wouldn't use them (for reasons I've mentioned) but a few guys have asked about them so they are available too

vive la democracie

[Careless]

Since this seems to be the new classifieds section, keep an eye out in the real classifieds, as I'm going to be parting out my R in the comming days and weeks. Everything goes except the body, which is an original Nismo R32.

 

 

 

lemme know when this happens.

[Careless]

I really don't see the need for oil restrictors either. I mean, there already is one in there... and perhaps just chamfering the drain holes on the block deck and making sure the head gasket holes have clearance and do not inhibit drain back would be sufficient, and if you're still worried about oil pooling up in the head and causing loss of oil in the sump, add half a little more oil, it's not that much and would probably still be below the windage tray.

 

of course. drysump system would be the bees kneez in this discussion!

[datsun dave]

On the Tomei head gasket kit do they inc a oil restrictor with it ?