10W-60 Synthetic Oil - Good or Bad Idea?
 

Hi guys

I'm running Castrol Edge Titanium 5W-40 oil in my supercharged AP1. The mechanic who changed my supercharger's belt for me recommended I use a thicker oil for more engine protection and if I'm going to lower VTEC to about 4200RPM because it will need more oil pressure the lower it's activated. He said go for mineral oil 20W-50 but I'm definitely not doing that! I figured Edge 10W-60 or Mobil 1. Is this a good idea? Will my engine, blower and lower VTEC benefit from that viscosity?

Thanks!

That is a bad idea, 5-40 is plenty and I would never go thicker

I think there was a recommendation from Honda here in Sweden to use Castrol 10W-60 for heavy track use.
I don't agree with it though and would never use it myself but I think many others did.

10/40 is the limit of what id go for. 10/60 is what the E90/92 v8 used. It has a much looser spec engine then the F20/F22. Id be worried about too high a pressure with not enough hot flow in 90% of the conditions your motor is going to be operating under and that in itself can cause oil starvation to parts not spec for it. Id invest in an oil cooler instead if your tracking. If just street, stick to a 40w.

That's what I thought. Thanks, I'll stick the the 5-40 weight I have now

Glad you mentioned heavy track use because Castrol markets 10-60 as "extreme conditions". Think I'll stick to 40 ;)

Yes you're right. The E90/92 M V8 uses that oil as BM spec. So no need in our tighter F20/22 eh? Nice :)
The mechanic just got me anxious saying I'm running boost meaning the engine is running faster/hotter and lower VTEC requires higher oil pressure. I have an upgraded radiator which is larger than stock so that adds to cooling. Will look into an oil cooler later on.
I'll stick to 40 full synth. Any comments on Castrol Edge?

This sounds like old school thinking. More load, thicker oil. Thicker is better.

Back in the day tolerances were very, very loose compared to modern engines. Even more so modern performance engines.

That thinking just doesn't work anymore.

once you are above 3000 rpms there is plenty of oil pressure , the oil pumps on our engines move huge amounts of oil so no worries about lowering vtec.

10w is the cold temp rating on cold starts, you don't need a 10w oil. As far as the operating temp same rating 60w, that's beyond too thick a viscosity. 5/40 is a good weight to run full synthetic - just my opinion and we all have them regarding different oils and weights. Good luck with it. Also, you mentioned casteol edge- I'm running 5/30 full synthetic same brand in my s2000- just bolt one no major mods - seems to be pretty good.