My AP1 now put back onto the road for the summer has just over 35,000 miles. This is the 1st year I have gone to synthetic, and the reason I have done so is because this car gets 8 to 12 track days per year and some autoxing tossed in on the side.

I have read before how some people think the VTEC transition gets smoothed out after switching over to synthetic, and right now I'm starting to suspect the same thing.

Has anyone done a dyno pull with their S with regular oil, and then done another pull after switching over to synthetic, all other variables being kept the same? Am I hallucinating, is my VTEC transition smoother because of the synthetic and if so, is it making more power?

 

here's my dyno numbers.
Im was on Amsoil ATM 10W30.
Jasonoff was running GCastrol 0W40 and
I believe Toosteeley was on dino.
We all ran the same numbers +\-3hp
I felt no difference in VTEC transition. Hits hard from day one.

 

Ian... I hit a 205.8 hp / 135.X tq that day.

Running GC 0W30 and air box cover off.

 

Bastard...that doesnt help triple-h's question at all then..

 

Any differences you perceive are likely mind tricks. No human on earth could detect such minute differences.

Today's conventional oils perform as well (in some cases better!) than synthetic oils. You won't gain or lose any hp just by switching from one to the other.

 

 

On the BOBISTHEOILGUY forum I have seen a study done by Shell about oil film thickness and their relation to engine wear.
There also was a tabel that showed the total loss of friction from valve train, bearings and piston assembly with different kinds of oils in a 2.0 liter engine @ 7500 rpm (described as a conventional European design, most likely Alfa Romeo, but thats IMO)
The worst was 20W-50 with 1942,5 Watts lost and the best 0W-20 with 1282.4 Watts lost.
The difference = 660 Watts = 0.66 kW = 0.89 horse power (1kW = 1,36 HP)
There is more power lost in pump losses but that wasnt in that tabel.
Lets say, for argument sake, that is as much as the rest, then the total would be 1,6 horse power between different types of oils.
On this I have to agree with Wisconsin thats just mind games.

Note that the engine was warmed up before doing that test.

 

synthetic=longer change intervals, and is SOME cases better protection, usually in higher mileage engines. i use a synthetic blended oil $3/qt rather than a $5/qt for full so it isnt too expensive, it gives me peace of mind since i have a higher mileage engine.

 

Interesting stuff guys, thanks.

Now that I have actually gotten to drive the car more I'm not so sure the VTEC transition has changed, I'm wondering it it was/is all in my head... Maybe the past 5 months of driving around with 379 foot pounds of torque has me a bit confused.

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So, what blends of dino+synth are out there? I see Valvoline has one and it is just a blend. I see Penzzoil has one but they say it is for SUVs and Trucks (5W30 and 10W30). I started this year with the Valvoline DuraBlend but would like to go to another brand.

I just can't justify a full synthetic because often enough in order to go to each school with clean oil I'm doing changes below 3,000 miles of use. Can I use a blend that says it is for trucks as long as I use the right weights of 5W30 and 10W30?

 

I would probably just use a full dino oil for that. I think RR has a recommended one in the oil journals, Havoline I believe, but I'm not sure.

Is it actually necessary to change the oil prematurely for the DEs that you do? If you ran a full synthetic such as Mobil 1, I would stick to a 3-5k drain interval no matter what the driving, maybe slant it to one end or the other depending on how many track miles the car saw during the interval.

If it's just for peace of mind, I guess I can't argue with that.