"I look at inefficiencies in a system and work on those first before compounding power and other issues into the mix". This is not completely different this is normal and very standard in a professional approach to increasing the performance of an engine. "Just because its worked for some doesn't mean it works for all and not to mention just because it works doesn't mean its right". Correct no one has said the stock oil system is perfect, we have simply pointed out it works and is not the imminent cause of death you appear to have claimed. It's almost standard procedure for virtually any car to go nuts on the oil system when you get to the stage of slicks and a cage be it for strip or circuit BUT as said MOST here wont go that far. MOST here are simply building fast street cars, they will find plenty of other ways to kill the engine before the oil system becomes an issue.
Out of all the vg30de or tt's I have pulled down. I would say a good majority had very worn rod bearings, but mains that could have gone again with out too much question. Although most failures are overheating or bad tuning, most have abnormal rod bearing wear which indicates an oil issue. The issue, like tech says, is the low speed oil system, but the biggest problem is not that the crank is cross drilled but how the big end galleries intersect at the main journal. This causes the oil to be taken away from the rod bearing, almost pumped out of it at very high engine load and speed. Quite easily rectified during a build. I have a hp/L limit I like to use before drastic mods become necessary, not too many people want to throw big wads of cash into an engine whent he money could be better spent elsewhere. Out of the 150 plus Vg's that I have built, only 3 of those warranted messing with the crankshaft oiling imho.
Ok, what are the technical/physical differences between the "Low" and "High" Speed Oil Systems? Google has nothing.
We've found VG's oiling system to be one of their strong points, although still require quality oil and regular change, especially if racing. We have been racing for over ten years now and never had a bearing problem. The last motor did 40+ track days and never left the engine bay. We did run big oil coolers and high quality oil, modified the sump slightly and for the first 2-3 years of this motor we ran an Acusump. Any improvements though can only help. We run a proper harmonic balancer though and if you don't it will be a problem. a2zed if you've built 150 then we've built 15,000.
:rofl: Waiting for reply ........ Still waiting :rofl: I'm very interested to see where the line is drawn in Mr EPRs mind to say this is low speed but that is high speed. You have to admit it would be very surprising if one of the biggest manufacturers out there used a system that was not appropriate in their flagship sportscar (at the time GTR came after). Most other systems in the car were state of the art so why would they go all 'that will do" on the oil system in the engine? There was a lot of thought put in to it you can be sure of that & if it truly were a big problem then there would be an information trail going right back to the first bigger power builds. On one hand stock girdle good for 1500Hp, on other hand stock oil system no good for ~500Hp but then happy to tell every one it's inevitable my engine will throw a rod. Whatever.
I am not trying to score points with this question ... am genuinely interested in what the differences are. My gut feeling is/has been the oil system is inadequate in that the sump volume is just too small so in high rpm and high speed cornering situations the thing just runs out of oil. In this case the factory DID sell the car short in the interest of keeping cost down over what should have been done. So if there is anything else that needs to be looked at, where is the info. so I/we can make educated decisions on what does or doesn't need to be done to the oil system.
I know you're not stirring mate The factory added the extra capacity to the side of the sump and added windage aids and a couple of baffles, I'm not sure why they would have stopped there if it still didn't quite do the job? The sump, oil pump, crank and block are all heavily modified from the VG30E so why would they design it short of the mark when there would be no significant costs to go further? Sure a full blown race car needs more than what a street car needs - that's a no brainer.
The bit they added to the side brought the sump capacity up to only 3 liters, I would suggest this is the bare min. they could get away with. In fact the manual says 4 liters without the filter, I measured the sump capacity, would only hold 3 liters, so, looks like the engine needs 1 liter to supply the Bearings, Lifters, Turbos and the VTC ... and I would suggest this would be under "normal" operating conditions and hoping like hell no would "race" it. Adding another "wing" to the sump on the driver side gets in the way of Oil Filter so they would have had to either re-locate this or run a remote filter system. Anyway...
yeah it is a little low but enough for street use the high volume Specialty Z sump (with trap doors) along with bigger oil cooler/s fixes all that.... .... Just curious Are there any dynochart results from these engines being built from EPR ? only seen heaps of builds and projected results ..
how many cars do you think the vg30 platform was installed in? The VG30 was originally an economy engine and with the introduction of the Z32 the VG30 was the choice of engine for the outfit. Obviously alterations to the engines were made to make them a bit more robust but the internal workings were left the same. Nissan isn't going to make a specific change to an oiling system for just one car. They were mass produced. Stock oiling system needs a bit of work but a race car that has 1500 doesn't have a stock oiling system. Its been modified quite extensively. But you also have to remember that back when the Z32s were being raced a lot of the technology we have now wasn't focused on or even being used.
Mitch, at the risk of devulging your secrets. What do you change to bring the the oiling system up to scratch ?
well first approach is modifying the oil pump. From there the second alteration is the oiling of the crankshaft. I modify it to run like a chevy oiling system. Third is to modify the oil gallies througout the block. Those three things i've found have resolved a lot of issues with how the oil is supplied to the bearings and gives the engine a better approach to oiling the bearings and so forth.
Adding an Accusump is one way to increase oil capacity, with the special metering electric valve available the Accusump basically becomes an additional reservoir. On the EPR big power projects, believe it when you see it. Not saying Mitch is making stuff up, after all he can only build what customers pay for. But 1500 real hp using a stock block? Dreaming
VKM Motors uses a stock block...Escort Racing uses a stock block...Blazt Racing uses a stock block...all are making 1000rwhp or more. I don't know why you think not achieveable.
Because there is insufficient support for the crank, the block does not extend past the crank centerline to support the sides of the main caps so basically all that holds the crank in place are the studs. Two per bearing. And, as mentioned previously, racing experience with the original single cam VG which, stock, uses the same crank support. A drag car doing a few seconds at full power does not count, that's play stuff, I'm talking about holding full rpm and power for say 60 seconds at a time, minimum. Like proper race cars
yeah I decided to not go with the accusump and relying on the sump design to keep the pick up covered ... and with the the twin oil coolers will be over 8 litres
so a car running 6secs down the track doesn't experience significantly more stress and abuse than one that runs for 60 seconds on a cirlce track? You're looking at two different varients. A drag car is a proper race car as well. Racing isn't just on a course.
I believe you. But what happens in the real world when you get a little detonation at 1,000hp+? Drag cars and dyno queens don't really count in the real world. Just about every blown VG I know about was a cooling issue, seen some rod bearing damage but it's often from detonation. Everyone's right, you're just on different pages. As a mild street-car the oiling system is fine if you change your oil, extreme street-car would maybe need thought. In uber-extreme applications which really is the context of this post? Lighten up guys. :zlove: All good info. Now what is it left or right bends I can't go around fast? (Nissan could have done better!) No disrespect to drag cars either, they are real race cars... but they're probably the most removed type of race-car from the real world, circuit racing applies to the real world more I feel.
