Jump to content
SAU Community

Recommended Posts

just a quicky and not sure if it should be in this section but here goes, im doing some work on my motor and i have been asked if i would like to put a sump extension on the RB to hold more oil, the car will be seeing some track work and i am getting this at a good price so are there any cons to doing this mod. all i really know is that we gonna need to cut my original sump and weld the aftermarket one on.

thanks.

Link to comment
https://www.sau.com.au/forums/topic/110090-rb26-sump-extention/
Share on other sites

My concern with the simple weld on extension kits (Trust, Tomei etc) is that they hang quite low. If your car R already has lowered suspension, there is a real risk of sump damage on speed humps and curbs.

I went for the Hi Octane sump as shown below

IMG_00441.jpg

Expensive but very well made and better clearance and capacity than the weld on kits.

Edited by Gav

Gav's sump is through Hi Octane Racing and are built by Performance Metalcraft (I've got one too).

Interior has windage doors made from metal plate and are exceptionally well made. Cost (by the time you add freight etc) is close to $2K. I had been running a Tomei kit along with an Accusump and gallery restrictor plug and recently spun bearings.

From what I have been told, many of the off the shelf articles are great for street but are not designed for track - and cannot cope. I had considered getting someone else to make the sump extension (a little cheaper) but these guys have been doing this for some time and have been through the experimentation phase already. The sumps they build are supposed to be as good as you can get prior to going to a dry sump. Capacity goes to about 8 litres for the GTR. Engine is going back together now so I'll get to try it out before too long.

thanks mac, they do look the business that's for sure. hell of a price tag though, but if you have say a $20K build (which i'd say Gav is and then some) then i guess it's relatively cheap insurance.

modified head or not?

Yes, head has been ported and polished with full bench testing, Tomei Poncams and gears

thanks mac, they do look the business that's for sure. hell of a price tag though, but if you have say a $20K build (which i'd say Gav is and then some) then i guess it's relatively cheap insurance.

Especially at the moment. Scored the journals on the cranks which meant I needed a new one - trouble is, Nissan ran out of GTR cranks in November and no-one yet knows when thay are going to start making any more. No doubt they will, but when. I waited 6 weeks and finally found one through a GTR forum in the UK. Aparently these are the SH1T!!

Yes, head has been ported and polished with full bench testing, Tomei Poncams and gears

I think he meant modified the cylinder head for increased oil return to the sump. We drill the oil return galleries and smooth the oil flow passages with the die grinder. Plus we fit an external oil return from the rear of cylinder head direct to the sump. Add this to the oil restriction (one feed restricted and one blocked off) in the top of the block and you have a good chance of the oil staying in the sump, not being trapped in the cylinder head. Or filling up your catch can.

TIP; If ordering the sump from Performance Metalcraft make sure you specify a fitting for an oil temperature sensor. Plus a fitting for the external oil return hose into the top of the LHS wing.

:P Cheers :P

I think he meant modified the cylinder head for increased oil return to the sump. We drill the oil return galleries and smooth the oil flow passages with the die grinder. Plus we fit an external oil return from the rear of cylinder head direct to the sump. Add this to the oil restriction (one feed restricted and one blocked off) in the top of the block and you have a good chance of the oil staying in the sump, not being trapped in the cylinder head. Or filling up your catch can.

Thats what i was getting at... a stock head, expect to spin a bearing or two.

The sump is a band-aid solution (and more costly aswell) if you are still using an un-modified head.

Just woke up and checked the thread (we're 9 hours behind in Bulgaria - physically and figuratively speaking).

OK - below is a pic of the internal swing gates. Note the hinges (gates) only swing internally both laterally (retaining oil level around the pickup on corners) and at the rear (for hard acceleration).

DSCF0841.JPG

My last custom sump (made localy in Perth) failed at the welds and the gates weren't as good quality and reliable.

Edited by Gav

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • This is the other log file, if only we had exhaust manifold pressure - would understand what's going on a bit better   Can you take a screenshot of your wastegate setup in the Kebabtech?   Engine Functions --> Boost Control (looks like this):  
    • You just need a datalogger of some sort. A handheld oscilloscope could do it, because it will make the trace visible on screen, so you can look at the peak, or whatever you need to look at. And there are cheap USB voltage loggers available too. You could get a 2 channel one and press a button to feed voltage to the second channel at points that you want to check the sensor voltage, when you knew what the guage was saying, for example.
    • it's not the issue with making power, it's the issue with controlling boost, and this isn't the first time I've seen a 6Boost having issue with controlling boost down low.   The boost control here looks interesting.   Looking at your logs, looks like it's set to open loop boost control strategy (which is fine). We can see VCT being kept on till about 6600RPM (no issue with that). Ignition timing (I'm assuming this is E85, seems within reason too, nothing too low, causing hot EGTS and boost spiking). There's about 15 degrees of advance when your boost shoots up, however can't be this as the timing isn't single digits. I'm assuming there's no EMAP data, as I wasn't able to find it in the logs. We can see your tuner sets the WG DC to 0% after 4300RPM, trying to control boost.   My thoughts, what frequency is your wastegate set to?  AND why aren't you using both ports for better control?
    • While that sounds reasonable, this is definitely a boost control problem, but the real question is why are you having the boost control problem? Which is why I pondered the idea that there's a problem at ~4000rpm related to head flow. In that instance, you are not yet under boost control - it's still ramping up and the wastegate is yet to gain authority. So, I'm thinking that if the wastegate is not yet open enough to execute control, but the compressor has somehow managed ot make a lot of flow, and the intake side of the head doesn't flow as well as the exhaust side (more on that later), then presto, high MAP (read that as boost overshoot). I have a number of further thoughts. I use butterfly valves in industrial applications ALL THE TIME. They have a very non-linear flow curve. That is to say that there is a linear-ish region in the middle of their opening range, where a 1% change in opening will cause a reasonably similar change in flow rate, from one place to another. So, maybe between 30% open and 60% open, that 1% change in opening gives you a similar 2% change in flow. (That 2% is pulled out of my bum, and is 2% of the maximum flow capacity of the valve, not 2% of the flow that happens to be going through the valve at that moment). That means that at 30% open, a 1% change in opening will give you a larger relative flow increase (relative to the flow going through the valve right then) compared to the same increment in opening giving you the same increment in flow in outright flow units. But at 60% opening, that extra 2% of max flow is relatively less than 1/2 the increase at 30% opening. Does that make sense? It doesn't matter if it doesn't because it's not the main point anyway. Below and above the linear-ish range in the middle, the opening-flow curve becomes quite...curved. Here's a typical butterfy valve flow curve. Note that there is a very low slope at the bottom end, quite steep linear-ish slope in the middle, then it rolls off to a low slope at the top. This curve shows the "gain" that you get from a butterfly valve as a function of opening%. Note the massive spike in the curve at 30%. That's the point I was making above that could be hard to understand. So here's the point I'm trying to make. I don't know if a butterfly valve is actually a good candiate for a wastegate. A poppet valve of some sort has a very linear flow curve as a function of opening %. It can't be anyelse but linear. It moves linearly and the flow area increases linearly with opening %. I can't find a useful enough CV curve for a poppet valve that you could compare against the one I showed for the butterfly, but you can pretty much imagine that it will not have that lazy, slow increase in flow as it comes off the seat. It will start flowing straight away and increase flow very noticeably with every increase in opening%. So, in your application, you're coming up onto boost, the wastegate is closed. Boost ramps up quite quickly, because that's really what we want, and all of a sudden it is approaching target boost and the thing needs to open. So it starts opening, and ... bugger all flow. And it opens some more, and bugger all more flow. And all the while time is passing, boost is overshooting further, and then finally the WG opens to the point where the curve starts to slope upwards and it gains authority amd the overshoot is brought under control and goes away, but now the bloody thing is too open and it has to go back the other way and that's hy you get that bathtub curve in your boost plot. My position here is that the straight gate is perhaps not teh good idea it looks like. It might work fine in some cases, and it might struggle in others. Now, back to the head flow. I worry that the pissy little NA Neo inlet ports, coupled with the not-very-aggressive Neo turbo cam, mean that the inlet side is simply not matched to the slightly ported exhaust side coupled with somewhat longer duration cam. And that is not even beginning to address the possibility that the overlap/relative timing of those two mismatched cams might make that all the worse at around 4000rpm, and not be quite so bad at high rpm. I would be dropping in at least a 260 cam in the inlet, if not larger, see what happens. I'd also be thinking very hard about pulling the straight gate off, banging a normal gate on there and letting it vent to the wild, just as an experiment.
    • Not a problem at all Lithium, I appreciate your help regardless. I've pulled a small part of a log where the target pressure was 28psi and it spiked to 36.4psi. I've only just begun using Data Log Viewer so if I'm sending this in the wrong format let me know.
×
×
  • Create New...