Cheers for the post, never known an engine be so temperamental to oil velocity index. Lad on the forum with owns a garage near Oxford, advised the same Millers Nanodrive 5w40 is what he uses in his DE and it since doesn't use a drop. Depending on what this does to warm idle pressure, might be just the ticket. I would rather use a bit of oil and have to top up and maintain a lower pressure. Lower pressure results in better performance, lowering the resistance inside the engine. It's very much a trade off between performance and protection.
For the last 6 oil changes ive swapped oil brands to feel which i liked and got on with in terms of response, consumption and engine quietness. Looking back ive tried the following:
Fuchs Titan GT1 5w30 C2
Used previously in a tuned SR20 and rated it, hence it being my first choice for the service. Used a noticeable amount oil, ish 800ml until the next oil change however i had been on track a few times that year so its to be expected. Overall very happy and for the costs, big thumbs up.
Shell Helix Ultra 5w30 AG
Used for all of 1 month and did another oil and filter change as it was absolutely shocking!!! During the first drive to work and once warmed up, put my foot down on a slip road to join the A45 Meriden and it honestly felt like i had the handbrake on 2 clicks. The engine felt so gutless i thought the newly fitted magnetic sump plug was attracting the crank. Wouldn't recommend for any application, other than a Vauxhall Combo van.
Motul 8100 eco-nergy 5w40 A5/B5
Heard very good thing about this oil so of course gave it a try, now being very aware of the affect oil blends can have on the VQ35 if you're paying attention. Felt ok, nothing special - a country mile better than Shell Helix AG however engine didnt feel as fruity or as eager compared with Fuchs Titan. Few more track sessions and the 10 litres bought initially (engine consumed 1300ml of it) was discarded into family members engines as top ups over the coming years. Used more than i would expect as i found out that one of my cam solenoids was all gunked up from sealant, plus made the mistake of starting the engine for a moment with these removed in an attempt to flush out any remains. The pressurised oil fountain was something to behold
Fuchs Super Syn 5w40
Back to what i knew and went for a 5w40 grade. Engine felt great again and had minimal consumption. Warm idle oil pressure went up noticeably on the gauge compared to all other 5w30's and i do prefer a slightly lower pressure for engine response and feel it must work the pump a tad less. No track action so weren't able to really compare with that regard, however routinely im happy to check and top up as and when needed. Again another very good showing from Fuchs.
Castrol Magnatec Stop-Start C3
Again used Magnatec in my old SR20 for years and years and never had an issue with it. Paying attention to the blend, visually to shake in a clear bottle (500ml left under the boot floor for top ups) the fluid has an almost elasticity/slime charater about it. All other oils I've used would come to a gradual rest slopping side to side in the container, this would come to rest abruptly as if it had memory. Very bizarre and never experienced anything like that this side of Nan's Sunday trifle. Funky magic fluid business aside, engine felt great and last year getting back out on track engine felt great. Warm idle temperatures higher than with the other 5w30's which peaked my interest. On a plus note, @cob1980 mentioned at the last midlands club meet of 2019 just how quiet the engine sounded being right up close. For the costs, very oil consumption would recommend for any daily VQ35 owner.
Millers Trident 5w30 C3
This will the 6th different oil ive tried and not much to report as yet, cars not come off the drive sadly. Will be looking for warm oil pressure, engine repsonse, engine quietness and road daily driving consumption. Catch can is drained every other year due to the low annual mileage.
EDIT - almost 6th months later using trident 5w30 and it's a keeper. Warm idle is exactly where is should be 12-15psi and the engine feels nice and lively when pushed. Topped up by 400ml in this time, no commuting due to lockdown mostly nice drives out/fast road. Also the oil is starting nice and clean when checking the oil level which hopefully is a good sign of being well looked after. First couple of oil changes I did it came out very dark.
For the price and as well, £22.50 delivered for 5ltrs it's a very good oil for the VQ35DE.
