Power difference from oil change

[eggstatic]

Hi all,

First time posting about my NC MX-5. Been a good car so far, only had her for about a month.

At first it seemed to be fairly zippy and and rev happy, but then I took it for an interim service. Since the service, it just seems to be a little slower going through the lower gears and it looks like it can be affected by temperature outside.

They apparently used the correct Mazda 10W-40 (or 5W) which is recommended for the MX-5.

1. I want to ask, am I being silly or can the specific oil used make a difference in how responsive a car is? Otherwise what are my other options for getting a bit of power back?

Also some more questions:
2. For you NC MX5 drivers out there, how much does your car struggle up an uphill when say going 60 km/h in gear 3.

3. If I wanted to do some noticeable performance stuff (prob. not turbo at this stage) - what kind of things would I need? Slightly interested in the turbo option as well.
Any places you could recommend in Sydney?

Thank you

[hks_kansei]

Oil won't make a noticable difference.

Unless it's been filled with something as thin as water, or as thick as vaseline, it won't be any different.
And if the oil is too thick, or too thin, you'll know because you'll eventually stuff the engine (too thin it doesn't provide enough protection, too thick it can't get to where it needs to)


I'd say you're either imagining it, or it's something else causing the change.

[taminga16]

Let us know where you are that you may catch up with some like minded NC owners who can review your concerns.
Greg.

[Magpie]

What fuel do you use 91, 95, 98 or an E blend?

[eggstatic]

I put in 98, how does this affect?

[hks_kansei]

I put in 98, how does this affect?

Different petrols can have a noticable affect on engine power etc.

Especially different octanes (say 98 vs 91) and even the different blends petrol stations use (the fuel you get in summer is different to the fuel you get in winter, they change the blend to make cars run better in winter etc)

Each brand also has slightly different blends, a car that runs great on BP 98 octane might feel a bit crap on say Shell 98.

[eggstatic]

Different petrols can have a noticable affect on engine power etc.

Each brand also has slightly different blends, a car that runs great on BP 98 octane might feel a bit crap on say Shell 98.

Interesting, I always tend to use Shell, but might give BP a go.
What's been your experiences with petrol types and mods in general HKS_Kansei?


Also, I've just been reading the following oil articles: http://ferrarichat.com/forum/faq.php?faq=haas_articles

- Am I coming to the conclusion that a thinner oil, eg. 5W-30 would have been better for my car than say a 10W-40 - again whether this has better performance I don't know - but in theory a thinner based oil should provide more lubrication and 'flow' than a thicker based oil (I know I am grossly oversimplifying it )

[JBT]

I've tried every brand and everything from the minimum recommended 95 E10 and up in mine - no difference except with the ethanol blend stuff when the fuel consumption increases. I just use Vortex 95.

[eggstatic]

@JBT: How do you rate the performance of your NC?

Just another thought with Oil, because there is some time for the car to warm up the oil
on a cold start (i.e. The oil would have started to get thicker overnight), would there be an initial delay in getting the best of the engine until the oil had warmed up enough after a bit of an initial drive. (i.e. Noticeable on daily initial short drives, etc..) ??

[hks_kansei]

Re the Bp and shell, I just plucked 2 brands out of the air for an example, I wasn't actually saying any one is better.

I don't even know what fuel is mine, since I only put fuel in maybe once every 2 months (my partner drives my car to work, I only use it on weekends and usually she's already filled it during the week)


As for oil, you're correct that thinner oil flows faster and gets to more areas.
But, thinner oil also has less protection by virtue of being thinner (pressure can push it out of gaps where a thicker oil can stick)

In saying that, 5w30 should be fine since it's not that much different to 10w40, the owners manual should list what's ok.
As long as the manual says it's ok, it's fine.

But yeah, thinner oil is better, but only if the engine is designed for thinner oil to start with.
For example, my other half has an old Kingswood, the engine in them is pretty agricultural. A thin oil in that would basically kill it in a day. It needs a thick oil.

[JBT]

Just another thought with Oil, because there is some time for the car to warm up the oil on a cold start (i.e. The oil would have started to get thicker overnight), would there be an initial delay in getting the best of the engine until the oil had warmed up enough after a bit of an initial drive. (i.e. Noticeable on daily initial short drives, etc..)

The oil should be good to go from start up if it's in the recommended viscosity range. Just drive the car a bit granny like until the temps are normal. Idling to warm the car up is not recommended.

I use Penrite HPR5 (5W-40) and have also used Shell Helix Ultra 5W-40. Both work perfectly from start up. The only time I noticed any change in the performance of the car was after replacing the spark plugs at 90,000km. It seemed more peppy then but otherwise, it just runs the same as it did from the day we picked it up new.

If you think the performance has dropped, take it back for a review. Did they drop your tyre pressures? The only thing I used to pick up after a dealer service was the tyre pressures would be up somewhere silly like 36-38 psi and just about shake my few remaining teeth out.

[eggstatic]

If you think the performance has dropped, take it back for a review. Did they drop your tyre pressures? The only thing I used to pick up after a dealer service was the tyre pressures would be up somewhere silly like 36-38 psi and just about shake my few remaining teeth out.

I did take it back for a review and he was ripping it around and it seemed okayish.

Don't you mean they increased your tyre pressure? Isn't 36-38 psi high?

[smy0003]

May have gotten a bad batch of fuel?
Either that or you've left the hand brake on ;)
Most likely in your head though, try not driving it for a day and coming back to it with a clear head.

Sent from my GT-I9505 using Tapatalk

[JBT]

Don't you mean they increased your tyre pressure? Isn't 36-38 psi high?

Yes, that's what I was indicating - I normally run 30-32. I just thought if they could increase mine by 4-6 psi that they could just as easily have dropped yours to 26-28 or something.

Good points there about park brake adjustment - unlikely, or crook fuel - more likely.

[eggstatic]

Turns out the tyre pressure was between 39-40 psi, Ive dropped it to 29 but will probably change it to 31psi - because there seems to be too much body roll.

I think the performance may be slightly better with the lower pressure.

Any thoughts?