Good oil

[method]

Looking at some of castrols edge or what ever it is. The fully synthetic oil

some weights are MUCH cheaper than others, anyone know why?
Obviously oils with a wider range cost more to produce and are more prone to breaking down at high temp due to longer polymer chains etc etc etc, so require some tech manufacturing processes. But double the price?? Was quite surprised how cheap some of the weights are!

25-50 is $42
5-30 is $60
10-60 is $90
0-40 $90

I usually run a valvoline performance kinda oil 10-40 blend in my turbo 4age.
But if i can get a 25-50 for the same price that is fully synthetic maybe i should run that? Especially with the higher temps due to the turbo, i've had the whole exhaust housing red hot. Plus i've always wanted to try a slightly thicker oil in the car too.

[Bazda]

Pennzoil do a 25/50 in their GT racing range.

check out their website for the racing series oils.

[Lloyd]

Why fully synthetic? More expensive doesn't make stuff better

As above, look at the Pennzoil stuff

[fuel]

25-50 is for 'big bore' engines, ie dirty old pushrod V8s.. the viscosity range is quite narrow compared to the broad offerings from 0W40, 10W60 etc.

a thicker oil (thicker than it's meant to run on anyway) can put more load on the oil pump, and it can heat up the oil just that little bit more. On the other hand it does cushion the bearings better and provides quite good protection.

4A-GE, due to their compact multivalve 4 cylinder nature would probably be better suited to a 0-40 or 10W40 etc.

[method]

What makes you say synthetic oils arn't any better?

I thought synthetic oils are more resistant to high temperatures and pressures/stresses and are less prone to break down than organic oils. Or whats what i thought.. Correct me if i'm wrong.

I know some people with high performance cars that swear by fully synthetic oils.

[method]

25-50 is for 'big bore' engines, ie dirty old pushrod V8s.. the viscosity range is quite narrow compared to the broad offerings from 0W40, 10W60 etc.

a thicker oil (thicker than it's meant to run on anyway) can put more load on the oil pump, and it can heat up the oil just that little bit more. On the other hand it does cushion the bearings better and provides quite good protection.

4A-GE, due to their compact multivalve 4 cylinder nature would probably be better suited to a 0-40 or 10W40 etc.

Ahh sweet, exactly what i was after! Cheers for that.

[escortman]

my engine builder told me never to run full synthetic oil even if its run it

[fuel]

theoretically synthetic oils are pretty good, but they don't allow an engine to bed in well. I made the mistake of using a semi-synthetic oil after 1500kms of running in my engine and now it's using a little oil, even though compression is still perfect and there is absolutely no blow-by.

I would probably wait until 5000~10000kms after a rebuild before using a synthetic oil.

[Bazda]

If its just a road car then you wont need 25/50, if you using it for track heaps I would reccomend 25/50.

[method]

If its just a road car then you wont need 25/50, if you using it for track heaps I would reccomend 25/50.

Why do you say that?

Its a road car, but only times it gets used aprox once a fortnight and every time it is used it gets a good cain. Thats what i built it for afterall. Can't afford to bring it to track that often but if i could it would be a "track car". Need to sort out the suspention on the rear end before i can call it a track car.

Engine is usually under quite a bit of stress. After a round around whenuapai/kumeu the manifold or even the whole exhaust housing is glowing red. It doesnt get hours of abuse end to end like a track car, just 30min or so at a time per outing.

[escortman]

i run pennzoil 15-40 mineral oil seems to be ok, only done 2000ks on the new motor though

[grantourismo]

been using castrol oil for ages runs fine LOL

[2jayzgte]

If your going for Castrol Edge products I use ther RS 10-60 I reckon its real good oil,done the job in my car for about 5 years now good product.

[IH8TEC]

penzoil gt racing or whatever 20w/50