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I finished my RB26 240Z


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Mark,

Glad to see you got the car out to TWS. While I was watching your video:

http://web.mac.com/markrolston/iWeb/Site/Z-Blog/0D6E575A-E65E-435E-A127-EC18E4F71405.html

I noticed the oil pressure was moving all over the place - and to near zero in right hand turns.

You never did say what kind of oil pan you have? I assume a custom job? After watching yours I'm going to pull my motor again and send the pan off for some mods - I didn't put baffles in it originally, but now I will - I don't want to spin a bearing after I let the pressure drop like that. Besides, I need to re-inforce the pan anyways since its such thin aluminum.

Its hard to tell with the way the video is cut - but that looks like low 2 min range at TWS?

I'm interested to hear what you think about your oil pressure.

-Bob

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Mark,

Glad to see you got the car out to TWS. While I was watching your video:

http://web.mac.com/markrolston/iWeb/Site/Z-Blog/0D6E575A-E65E-435E-A127-EC18E4F71405.html

I noticed the oil pressure was moving all over the place - and to near zero in right hand turns.

You never did say what kind of oil pan you have? I assume a custom job? After watching yours I'm going to pull my motor again and send the pan off for some mods - I didn't put baffles in it originally, but now I will - I don't want to spin a bearing after I let the pressure drop like that. Besides, I need to re-inforce the pan anyways since its such thin aluminum.

Its hard to tell with the way the video is cut - but that looks like low 2 min range at TWS?

I'm interested to hear what you think about your oil pressure.

-Bob

 

Stop the presses!!!!! if that is your oil pressure on the middle gage i would stop running it till you mod the oil system. This is why the stock rb does not do well on the track. Please for the love of god get that fixed before the Beautiful motor calls it quits.

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Stop the presses!!!!! if that is your oil pressure on the middle gage i would stop running it till you mod the oil system. This is why the stock rb does not do well on the track. Please for the love of god get that fixed before the Beautiful motor calls it quits.

 

Wow, Some of you really watched that video closely. Yes, the oil pressure was going all over the place and my oil pump did go out during that run. I shut off the engine immediately and was able to save the motor except for the main bearings. The accusump may have been priceless in saving the motor as well. I now have a HKS oil pump in there hopefully to keep the pressure up. We'll find out this feb when I get the car back out there.

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Stop the presses!!!!! if that is your oil pressure on the middle gage i would stop running it till you mod the oil system. This is why the stock rb does not do well on the track. Please for the love of god get that fixed before the Beautiful motor calls it quits.

 

Mark,

Glad to see you got the car out to TWS. While I was watching your video:

http://web.mac.com/markrolston/iWeb/Site/Z-Blog/0D6E575A-E65E-435E-A127-EC18E4F71405.html

I noticed the oil pressure was moving all over the place - and to near zero in right hand turns.

You never did say what kind of oil pan you have? I assume a custom job? After watching yours I'm going to pull my motor again and send the pan off for some mods - I didn't put baffles in it originally, but now I will - I don't want to spin a bearing after I let the pressure drop like that. Besides, I need to re-inforce the pan anyways since its such thin aluminum.

Its hard to tell with the way the video is cut - but that looks like low 2 min range at TWS?

I'm interested to hear what you think about your oil pressure.

-Bob

 

 

I also replied to Stony's comment about this- yes the pump was failing. It did fail. It split in two. ouch. anyway the oil pan has several nice baffles. That wasn't the problem I don't think. It was likely the pump itself not keeping up. But you certainly should baffle it.

 

I don't know what times I was making. The video is all cut up since it's normally 25min long. Honestly it was the first time at the track with the RB motor and I'm sure I was slower than I was with my race prepped L28. I was fast in that because I knew the setup well. This new setup is so powerful I'll need to get used to the setup. The power is also more of an on/off switch than the L28. Tricky to drive hard.

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There are many well documented cases of oil starvation on the stock rb26s I have not expeienced it but have read a bunch of articles on how easy it is ti blow a stock 26 on a road course unless newmourous oil system mods have been done. one is installing a restrictor in the head that keeps more Oil in teh pan. Larger sump and Hi volume pump are mandatory. Hopefully Motorworx (MATT) will see this and explain someMore one what you need to do to get teh rb out to track specs. 

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 Hopefully Motorworx (MATT) will see this and explain someMore one what you need to do to get teh rb out to track specs. 

 

 

Unfortunetly (sp?), thats not going to happen.... Matt gave us his farewells a while back, saying he wouldn't be back to this site (bummer, I know :-()...

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I showed the video to a little birdie friend of mine and this is what he told me....

That's not an oil pump issue. Being cracked can cause lower pressure due to decreased volumetric efficiency, but it'll be across the board. When the pumps fail hard enough to notice, it's catastrauphic. Zero oil pressure and a broken housing. The pump probably cracked due to cavitation.

 

That car is having sump issues. The pressure only zeros when turning right and under heavy braking. Standing it up can cause some drain-back issues, but the drains are in the rear and on the left, so turning right would return oil to the pan. Pans that have long, wide sumps, like Thagard's, require serious baffeling with trap doors to hold the oil in one small place around the pick-up. I can't imagine a Z31 pan having that problem, but his problem is 100% that the pick-up is uncovering on right-hand turns. Need to figure out why it's uncovering.

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I showed the video to a little birdie friend of mine and this is what he told me....

 

That's not an oil pump issue. Being cracked can cause lower pressure due to decreased volumetric efficiency, but it'll be across the board. When the pumps fail hard enough to notice, it's catastrauphic. Zero oil pressure and a broken housing. The pump probably cracked due to cavitation.

 

That car is having sump issues. The pressure only zeros when turning right and under heavy braking. Standing it up can cause some drain-back issues, but the drains are in the rear and on the left, so turning right would return oil to the pan. Pans that have long, wide sumps, like Thagard's, require serious baffeling with trap doors to hold the oil in one small place around the pick-up. I can't imagine a Z31 pan having that problem, but his problem is 100% that the pick-up is uncovering on right-hand turns. Need to figure out why it's uncovering.

 

That was my assumption as well - that the oil pump failed due to lack of oil, high rpm, which in turn = excess heat in the pump = failure of internal rotors.

Mark - I have the HKS oil pump and I know how much they cost - I'd lean with Matt on this one, (the "quote from a birdie"). He has built a lot of RB26's with significant power and seen lots of failures. I'd hate to see your new HKS pump fail with the same issue.

With your motor stood straight up vice leaning like stock, or how most of us have ours, your returns are in the cyl head are still aided right hand turns,(the drains on the left side of the cyl head and the rear). So that shouldn't be an issue.

The way it dropped off, then suddenly re-appeared was almost identical to my L6 oiling problem at the track, (insufficient baffling, led to significant bearing wear due to lack of oil in certain turns at 6000+ rpm).

I don't know what your oil pan looks like, or what the baffling looks like - but I, and I'm sure others, would be very interested in some pictures.

What I think really killed your bearings was turns 9 and 10. With 9 a hard right hander, followed by a short downhill to the long turn 10, the acusump couldn't re-charge between pressure falling off, and the real damage was done on the exit of turn 10. You can see in the video, on initial right hand turn, (into turn 9) the pressure drops to about 20 as the acusump takes over, then to zero after its depleted. It recharges as you charge down the hill, for about 2-3 seconds, then you brake again, and it drops almost immdeiately to near 0, with a fall to zero as you begin to turn. You also downshift to 2nd in that corner,(you can gain speed by leaving it in 3rd gear), and that just puts more rpm into the pump w/o oil. That is why I think turn 10 killed your oil pump.

I'm serious about seeing some pictures of your oil pan and its baffling - I need to see what I can do to improve mine.

BTW - do you have any videos of your car at TWS before the RB?

-Bob

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With the problem beening the sump/oil pan has anyone dry sumped a Rb26/25 engine ? it would take away the baffling issue

 

It was tried in our Z community, and abandoned due to complexity,(he has AC and power steering).

Here is that link:

http://forums.hybridz.org/showthread.php?t=109375

KAZU has a serious car which is significantly modified,(dash, suspension, etc.. - I wish he would drop in and give us an update).

I seriously doubt there is a dry sump setup out there since the front diff is integrated into the oil pan and there is fairly extensive baffling and crank scrapers already. It is only those of us putting the motor into a RWD setup which would consider a dry sump setup - and I haven't seen any.

-Bob

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I think KAZU's idea in that thread is the best bet - take an existing drysump,(some inline 6 cyl would be sufficient, L6 would likely be easiest) and adapt it to the flange for the a RB26. Then of course you have the oil tank, lines and the pump.

Here is a L6 sump:

http://www.drysump.com/pan16b.htm

And their main price list:

http://www.drysump.com/pan16b.htm

As you can see, its a near $600 pan that you would be hacking up to adapt to the RB26.....

I'm sure since they have a Computer water jet, they could cut just about anything for you. Of course the real cost is the plumbing, the pump and the tank - they'll quickly exceed the cost of the pan.

Surely with some adequate sumping, it should be fine. I guess that's why I'm anxious to see your sump baffling. My original thought had been just to run two across the motor,(left to right), in front and behind of my pickup. You can see my pickup in this post:

http://forums.hybridz.org/showthread.php?p=696138#post696138

Since the pan is shorter in that direction, it shouldn't need traps in that direction. I'm not sure if that is clear or not...

Here is a quick MS paint picture of the direction,(attached)

-Bob

trap doors_thumb.JPG

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Had a sump made some years ago for my race/sprint 240z the chap made and attached 2 wings to each side of the standard sump with a windage tray and trap doors to catch and trap the oil on hard cornering (after i killed a engine at Oulton Park Race Track) due to a hard sweeping bend, the wings each held a litre of oil extra to what the engine had, might give him a ring to see what he can do with the 200ZR sump

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That is a truely awesome piece of kit - Very inspiring indeed.

 

Love that video at the track! Was that white car in front of you a Mazda Miata??

 

Interesting thread developing about the oiling system too, looks like I will need to do some serious work on my 200ZR pan for my RB30DET powered track car.

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