240zdan Posted May 31, 2016 Share Posted May 31, 2016 (edited) First of let me tell you that I have had low oil pressure issues with my Rb26dett 2 years after doing the swap. Learn from my mistakes/experience. If you swapped a RB into your Z the first thing you should do is install an oil pressure gauge. I chose a mechanical gauge with braided oil pressure line. Upon warmup I was getting lower oil pressure than usual. After 4 years my oil pressure was around 58 psi at redline. I noticed a steady drop every year of trashing on the car. It seemed every year my peak oil pressure would drop. After a while I decided to drop the pan and check out whats going on. This illustration depicts exactly what I found (not my engine, but you get the idea) As the screws got looser, so did the oil pressure. While I was at it, I decided to upgrade to Reimax billet oil pump gears. http://www.rhdjapan.com/reimax-oil-pump-gear-kit-nissan-bnr32-bcnr33-bnr34.html Im making this post to raise awareness. If you don't have an oil pressure guage on your swap, get one NOW and make sure its a reliable guage. Next, determine if you had the same issue as I did. A little bit of Loctite goes a long way. The new gears arent necessary but for the $$ the billet vs sintered metal is a no brainer. Post up your oil pressure values if you wish, I was paranoid about my mine for the last 3 years, babied the motor. With the new gearset and loctite on the screws I have 80 psi at 5k+. She gets the beating she deserves now nonetheless . Having said that, a bit of decay at higher revs is somewhat normal from what I've gathered. But so long as that gauge is pegged around the 80 psi mark Im happy. Happy motoring Edited May 31, 2016 by 240zdan Quote Link to comment Share on other sites More sharing options...
Wizzurp Posted June 1, 2016 Share Posted June 1, 2016 Interesting issue, I need to get a (non datsun) oil pressure gauge in mine, it seems to have declined a little but I've also got a little flake in my oil so I suspect mains are getting some wear as I've got no noise. I'lll pull mine and check it out this summer sometime. Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted June 2, 2016 Share Posted June 2, 2016 There was also an issue on the early '90s engines of the oil pump drive on the crank being too narrow and breaking. They fixed it by going wider. Quote Link to comment Share on other sites More sharing options...
240zdan Posted June 2, 2016 Author Share Posted June 2, 2016 (edited) The narrowed crank drive doesn't have much to do with this post. There are heaps on info on this subject online, everyone has their own opinion. FWIW I stuck with the narrow crank drive when I upgraded to billet gears, for a few reasons. Don't think that nissan didnt narrow the crank drive for a reason, and the wide crank drive is not a solution by any means. Some people call the narrow crank drive an engineering error... please... you really think a company thats capable of producing the r32 gtr would narrow an oil pump drive on the crank for no reason? Yes, later model r32s and r33/r34 has wide drives, but did it fix anything? I have heard of oil pumps shattering with both. In most cases, (rare) they usually have one thing in common: line boring the block. Take a minute to figure out whats happening. Anyways, you're opening up a whole new can of worms here, if you'd like then make a new post about crank drives and Ill chime in. Im warning people about backing plate screws coming loose. Edited June 2, 2016 by 240zdan Quote Link to comment Share on other sites More sharing options...
BallZ Posted June 2, 2016 Share Posted June 2, 2016 This is a common issue with rb motors they're not actually made to be bounced off the rev limiter. Who knows how your engine was treated before you got it. Anyway this isn't a nissan issue it's a driver issue, there racing team figured this out long ago. It's actually a recommended upgrade for those that like to rev the piss out of the engine. Anyway thanks for the reminder better upgrade mine before I finish my swap Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted June 2, 2016 Share Posted June 2, 2016 (edited) The narrowed crank drive doesn't have much to do with this post. There are heaps on info on this subject online, everyone has their own opinion. FWIW I stuck with the narrow crank drive when I upgraded to billet gears, for a few reasons. Don't think that nissan didnt narrow the crank drive for a reason, and the wide crank drive is not a solution by any means. Some people call the narrow crank drive an engineering error... please... you really think a company thats capable of producing the r32 gtr would narrow an oil pump drive on the crank for no reason? Yes, later model r32s and r33/r34 has wide drives, but did it fix anything? I have heard of oil pumps shattering with both. In most cases, (rare) they usually have one thing in common: line boring the block. Take a minute to figure out whats happening. Anyways, you're opening up a whole new can of worms here, if you'd like then make a new post about crank drives and Ill chime in. Im warning people about backing plate screws coming loose. Wasn't saying you didn't know about it. And it does apply to this post. I was just mentioning it for those that hadn't heard about it. Did Nissan have it wider at first then made it narrower? I thought the first design was narrow and then the fix was to go wider? It makes perfect sense because the narrow gear has a much smaller contact area to transmit the load. Anyone that stays with the narrow drive is asking for trouble IMHO. Non of the AM pumps recommend the use of the narrow drive do they? Just look at the pic you've posted, it's digging into the drive surface. That shouldn't be happening and probably wouldn't if it was the wider style. All that surface area on the pump and the drive is only touching the edge of it. Thanks though for the heads up on the screws, will def put the red locktite on the build. Edited June 2, 2016 by Chris Duncan Quote Link to comment Share on other sites More sharing options...
240zdan Posted June 2, 2016 Author Share Posted June 2, 2016 (edited) They started out with a narrow drive, then changed to wide. I have a suspicion Nissan went with a narrow drive in 1988 as they were having oil pump gear breakage issues from the start. This was an effort on their part to solve it. Perhaps their theory was the less drive contact on the gear, the less damage to the gear, the longer itll hold together? Here is a full with driven cracked oil pump. As you can see, contact is still uneven due to crank deflection from higher rpms. There is just more damage done by a flawed one contact drive system. The full width drive isnt really helping anything other than helping to spread the impact along nearly the entire width of the gear. You can see on top of the contact patch an indentation, this clearly indicates crank nose whip or crank deflection. Or perhaps the gear was worn its pump case. So the reality is, a full width drive isnt much different than a narrow drive under extreme conditions, and both could potentially fail. Some may argue the full width drive spreads the load against the entire gear which makes things better. But in my opinion it isn't the load that causes failure, its the impact. Nissan didn't fix the issue by going full width drive, it may have made it better, but it didnt fix it. The ultimate solution is spline driven gears, or run billet gears in standard pump and just keep an eye on them say every 5 years. Whether its full or narrow drive IMO doesnt matter. I didnt want to pull the motor out, pull the crank out, machine it and press on a collar (which of them are made too tight to the gear anyways). I feel like the oil drive system is doomed regardless, and if I am going to do anything it will be spline driven gears. For now what I have works, and when I pulled out my OEM gear after 7 years of hard use it looked fine aside from a bit of contact wear. Honestley I think the only guys having issues are drifters and people who peg the limiter all day. Edited June 2, 2016 by 240zdan Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted June 2, 2016 Share Posted June 2, 2016 Agree with your thoughts now that I see what you're talking about. Also think problems are created by people going beyond or far beyond the factory HP. I'm just going to try for weight reduction gains, at least at first. Quote Link to comment Share on other sites More sharing options...
240zdan Posted June 3, 2016 Author Share Posted June 3, 2016 (edited) Yeah for sure. I think under 500hp and keeping the revs reasonable you will never have an issue. Also a good crank damper helps, alot of these motors have worn out dampers which will make matters worse. Its just a common misconception that getting a collar fitted or running a wide drive crank will fix the issue. I tend to disagree. Also the Reimax gearset I installed used the OEM case which uses thicker gears. Alot of the guys having issues are running N1 pumps which use sintered metal gears that are thinner than OEM, making matters worse. I think with a billet OEM style gearset its a pretty reliable setup for a sub 500hp street driven RB. Whether its worth it to "upgrade" to a wide drive.... I would say no. I think the billet gear will have no issues coping with either wide or flat drive. I will pull mine out in 5 years and let you guys know how it looks, haha. Edited June 3, 2016 by 240zdan Quote Link to comment Share on other sites More sharing options...
Wizzurp Posted June 3, 2016 Share Posted June 3, 2016 I'd like to hear other's definition of "keep the revs reasonable" I have my limiter set at 8k, I street the car, when I feel frisky it will spend a couple minutes at a time above 6k continuously. I hit the limiter ******* around quite often for what it's worth. Quote Link to comment Share on other sites More sharing options...
240zdan Posted June 3, 2016 Author Share Posted June 3, 2016 (edited) I have my limiter set to 7600 and hit it occasionally, but avoid it if possible. I usually rev to 7000 as my turbo (gt30r) runs out of steam above that. 500hp is easily doable with 7000-7200rpms on a RB. Edited June 3, 2016 by 240zdan Quote Link to comment Share on other sites More sharing options...
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