LS3 engine oil recommendations

[losh1971]

Any chance of a photo of the oil cooler location? I didn't know I had one.

 

[07GTS]

Any chance of a photo of the oil cooler location? I didn't know I had one.

its just a out/in port thats joined from factory, but can be used with the right fittings to run thru a cooler

 

[J_D 2.0]

Any chance of a photo of the oil cooler location? I didn't know I had one.

It’s on the side of the block above where the oil filter screws on.

 

[losh1971]

It’s on the side of the block above where the oil filter screws on.

Thanks, I'll have a look when it's next on the hoist.

 

[RevNev]

What we discovered with V8 Supercar engines is that light synthetic oil makes 2 or 3 horsepower over a 25/50 mineral-based race oil but in 1100 race km's, the light synthetic oil chops out the roller lifters and rocker gear and most are Jesel at 10k replacement cost. On mineral base oil, the lifters and rocker gear will get 4000 race km's which is the rebuild interval where the engines get pistons, valves, lifters and rocker gear. Conrods and cranks get double that to 8000 race km's before they're replaced.

Another oil phenomenon back in 2007 with V6 Ecotec race engines in 3 VT Commodores, the one on 15w50 Mobil 1 synthetic kept spinning big end bearings. The other two one on 20w50 Torco mineral base race oil and the other on 25w50 Castrol GP50 mineral base oil were fine, big ends and crankshafts perfect! We discovered they were oil surging under brakes and losing oil pressure but the mineral base oil engines with the same oil pressure loss, didn't suffer big end damage. The technically better, top of the line synthetic oil spun big end bearings at 3 consecutive race meetings. The fix was the addition of gated sump baffles but nevertheless, the old mineral oil protection was significantly better than full synthetic at the time!

 

[Skylarking]

Those Penrite oils with ZDDP are at levels that shouldn't **** the CAT.

I've been running those oils for a long time and have not noticed any issues on our car with reduced performance that a blocked CAT would exibit. Interestingly it also quietened my sometimes noisy lifters when getting close to the next oil change. I know it's a V6 motor but they are the exact same lifters as the LS motors.

My understanding is that the catalyst reacts with ZDDP/ZDTP ash which coats the catalyst with a thin glass(?) layer which stops the exhaust gasses contacting the ceramic catalyst rather than blocking the converter itself thus chocking off exhaust flow. I’d guess such would cause cat efficiency errors.

But I’ve got no idea what level of ZDDP additive is needed for this to occur and how long it would take before problems manifest…

However SN non/low zinc oils have 600-900ppm while the much older SF oils had 1500-1900ppm so it seems a mid point.

Interestingly the following articles allude to ZDDP levels in the oil at being around 1000-1400ppm would still allow catalysts to be warranted for a 10 year lifetime.

ZDDP in motor oil

cen.acs.org

ZDDP Engine Oil - Mustang Monthly

Get the inside scoop on everything you'll need to know about your vintage Mustang's engine oil and its need for zinc. More details along with photos only in Mustang Monthly

www.motortrend.com

The Effects of Zinc Oil Additives on Older Engines | Rislone

Almost everyone who’s into cars has an older vehicle that they love. Whether it’s the feeling that they get behind the wheel or the way the car looks parked in their driveway, they pour their time and effort into maintaining the car and keeping it looking like it’s just been driven off of the...

rislone.com

Whats certain is that old pre catalyst cars need zinc and must have zinc in their oils else they suffer engine damage if using modern low zinc oils. And it’s here where specialist oils and additives can make a killing

Maybe you’ve not reached the point where catalytic converter efficiency has degraded enough to be a problem but your cam lobes would be happier and probably like you more than your catalyst does

 

[lmoengnr]

What we discovered with V8 Supercar engines is that light synthetic oil makes 2 or 3 horsepower over a 25/50 mineral-based race oil but in 1100 race km's, the light synthetic oil chops out the roller lifters and rocker gear and most are Jesel at 10k replacement cost. On mineral base oil, the lifters and rocker gear will get 4000 race km's which is the rebuild interval where the engines get pistons, valves, lifters and rocker gear. Conrods and cranks get double that to 8000 race km's before they're replaced.

Another oil phenomenon back in 2007 with V6 Ecotec race engines in 3 VT Commodores, the one on 15w50 Mobil 1 synthetic kept spinning big end bearings. The other two one on 20w50 Torco mineral base race oil and the other on 25w50 Castrol GP50 mineral base oil were fine, big ends and crankshafts perfect! We discovered they were oil surging under brakes and losing oil pressure but the mineral base oil engines with the same oil pressure loss, didn't suffer big end damage. The technically better, top of the line synthetic oil spun big end bearings at 3 consecutive race meetings. The fix was the addition of gated sump baffles but nevertheless, the old mineral oil protection was significantly better than full synthetic at the time!

How often were valve springs changed on race engines?

 

[RevNev]

Whats certain is that old pre catalyst cars need zinc and must have zinc in their oils else they suffer engine damage if using modern low zinc oils. And it’s here where specialist oils and additives can make a killing

Particularly cast-iron head taxi engines VN to VY on LPG were hard on valve guides and K-line bronze guide inserts would fix them. But quite a few ran diesel oil and minimised the valve guide wear issue tenfold. I'm not sure what properties diesel oil had in comparison to conventional petrol engine oil but for some reason, diesel oil in LPG engines was far more valve guide protective.

 

[RevNev]

How often were valve springs changed on race engines?

1000 race km's on the Supercar engines, or every time the driver missed a gear and over-revved the engine with the old H-pattern Holinger gearboxes. There's a good Isky spring that's far more durable we used in the Kumho Series and running the car in Sports Sedans but costs a couple of horsepower the main game didn't use much.

The Sports Sedan engine was a VZ spec Garry Rogers engine we stroked to 343ci which raised the compression ratio to 11:1. It made 705hp @7600rpm on an engine dyno and in the car, shredded rear tyres from the additional torque. We had to run a taller diff ratio to offset wheel spin, but it was only a couple tenths faster at Mallala than the 5 litre 620hp engine and made the car harder to drive.

 

[greenacc]

I don't drive an LS but I figure the alloytecs use the same type of catalytic converters so this might give you a point of reference.
I use Synpower 5w40 in my alloytec. Synpower is very similar to HPR5, even the penrite rep agreed with that. They say it Synpower contains zinc just like hpr. So I've been using the same oil for over 10 years in the same alloytec. 150000km on Synpower and the engine and exhaust is now at 300,000km. I've replaced the oxygen sensors once but never had an issue with the cats. As far as I know they're still working fine.
I've just got a trust issue with 5w30 oils. I won't use them. I've heard of too many engines blowing up at low km running thin oil. So far my engine runs smooth as at 300k.
So the point is don't be scared to try. I highly doubt your cat will explode. We would be hearing about a lot of cat failures if hpr and Synpower caused those issues.