az55

I have seen lots of vague references to oiling issues with LS3 motors, but can someone clearly state where, when and how often?

I need a new motor for my racecar, and I want to know if I should eliminate these motors from my list. But I want to know the exact reason based on verified events, not blind conjecture based on third party stories.
: bigears: bigears

Cheers from Arizona.

SIK02SS

in SCCA T-1 racing before a 3 stage dry sump was allowed they would make it between 15-18 minutes in a 30min race iirc. Since the dry-sump they are doing okay..

maybe Chris Ingle can chime in with his first hand experience

ScaryFast

So what, specifically, is causing this? Isn't the LS2, 3 and 6 all the same block? Is it flow thorugh the heads?

I can't put a dry sump on my car, so do I need to avoid an LS2 or 3?

MySR71

This might be of interest:

http://forums.corvetteforum.com/auto...l-in-scca.html

trackboss

One thing I find interesting is that it is often mentioned that left hand sweepers hold oil up top in the passenger side cylinder head, but I have never heard the opposite. Has anyone thought that possibly the crank is slinging oil up the passenger side of the motor/resisting drainage and overfilling the crankcase will just amplify the effect? I'd think a crank scraper on the passenger side would help with this. The deep skirt block combined with extremely shallow corvette pan I would think is very sensitive to oil level.

96CollectorSport

If your looking for reliablity you cannot beat the LS6 long block from GM for $3300 you have a motor you can spin up to 7000 RPM all day long, it makes good power (our T1 car with stock manifolds and paper filter makes 385 rwhp) and it will last you about 2 years. Now if you put headers and an intake on the same motor you should easily be able to go to over 400 rwhp. Remember that we are talking about a motor that is tuned for 100 unleaded. That is why you don't see 93 octane cars making that kind of power.
Not saying that the LS2's or 3's can't be made to last they just don't have the proven track record that the LS6 does.

Power - Reliablity - Cheap - You can only pick two

If it were me the choice would only be between the LS6 or the LS3. (skip the whole LS2 thing they don't make enough extra power over the LS6 to make it even worth consitering. Remember they are using the same heads as the LS6 and heads are the key to airflow in the motor.)
If you want to spend the money and do the LS3 you better have the extra $5k to do the dry sump, otherwise get the LS6 and beat the $hit out of it.

wmckeenster

ScaryFast

Joel - LS3 automatically knocks me out of PTA...don't want one

wtknght1

If you are running racing tires, then do not run an LS3/2 on a track - the pressure will not keep the bearings from starving (among many other issues). The dry sump is the only solution that seems to work so far and I've tried just about all of them. The LS2 is quite as bad, but it's still a grenade with the pin pulled. When you turn left, the oil pressure plummets.

With the ARE sump that Phoenix installed, I'm seeing 45-75 psi all the time and much lower oil temps. And, there's no oil puking into the intake either. It works as advertised!!!!!! There's no performance advantage that we've seen, but the engine lives.

ScaryFast

Chris - I can't remember, is that a full dry sump system or a hybrid?

What does the system cost, roughly?

Thanks.

wtknght1

I don't know the difference to be honest. I know it's a 3-stage system that uses the stock oil pump. It's about a 3-gallon tank that sits where the battery is/was.

The system itself is "only" about $3500, but when you add in the battery relocation kit and all the lines, fittings and installation labor, it's about an $8K job. I also had an ENORMOUS oil cooler put on there too which you will need if you plan on really running the car hard down here in the south. I saw 246 degree oil temps at the ARRC on Saturday and it was about 70 degrees or so. I still expect to see 275-290 in August even with big cooler. The LS3 does run HOT!!!!

I don't know if the new GS dry sump works well or not, but the ARE system seems to do its job perfectly. I can't begin to tell you how happy I am that the oil pressures stay nice, high, and consistent! The Phoenix guys did a superb job with it!

trackboss

Taking the oil pan out of the picture, what makes the LS3 oiling different/worse, than the LS6?

igo380

Chris what oil cooler are you using? I was over 300 this weekend with the Z06 cooler.

wtknght1

I'm not an engine guy so I don't know all the issues with the LS2 and 3 internally, but I do know they load up the Right side head full of oil and a bunch of it gets puked into the intake. The oil simply doesn't drain down enough to feed the oil pickup tube. This has the biggest effect/affect on left turns.

The other big problem they saw especially with the LS3 is blow-by. The explosion within the cylinder literally passes by the rings and superheats the oil causing those ultra high oil temps. We saw over 330 even with a cooler. GM came up with a stacked cooler in series that kept it below 300. Without a dry sump, you'll most likely have do some type of cooler stacking to keep the temps below 300. If you have an LS3 and haven't seen those temps yet, it's because you aren't driving hard enough. It will get there!

My current oil cooler is enormous...a Setrab I think...12x12 or 12x16...whatever the biggest one they make...sitting right in front of the radiator to get a direct shot of cool air. The dry sump seems to limit the blow by some and helps to keep the oil cooler too. From what I've seen with this engine, you simply cannot get a big enough oil cooler...especially if you live in the south!

trackboss

If it's only the right side head then I'm pretty sure the crank is helping it. Too much oil in the sump combined with the cornering, deep skirt block with little bottom end breathing, shallow oil pan, and especially if there is an overfill of oil as many do, resists drainage. If the crank is submersed in the oil in the sump even a little it will sling the oil up the block fighting the oil trying to make its way down. A crank scraper and less oil in the sump will help that
One thing I recently did on my LS1 is throw away the factory lifters and the lifter cups. In their place I installed link bar lifters. They seem to have freed up a lot of drainage. I made some other changes to the oil system, but I think that was the biggest improvement. I have yet to get back to the track. One thing I did notice is that now I have quite a bit of vacuum in the crankcase with the factory pcv system hooked up (valley tube hooked up to vacuum source in the manifold and fresh air tube on pass. valve cover hooked up to non-vacuum tube on t-body) at idle. I really think removing the cups opened the drains up quite a bit so the vacuum can really pull.
I just built my own catch can and will be removing the vacuum source from the crankcase so it can just breathe as needed, and no chance of oil going into the intake from either of the breather tubes.
The blowby in the LS3 would be a ring problem. That could happen to any motor if the rings are not seated correctly.

NOSLO6

Thanks for posting this detail. Very helpful.

MikeFleischer

See this is very interesting since I spun the bearings on my LS6 (01 Z06) at Motorsports ranch (which has a decent left hand sweeper!) running Hoosiers also so it all adds up to oil starvation... GM was nice enough to replace the motor for me though back then!

Now has anyone retrofitted the LS7 or Grand Sport's dry sump to an LS2 or LS3? If so what is the cost there? Surely not 8K? How does 8K compare to a complete LS7 setup?

Thanks

wtknght1

I actually thought of that, but after talking to the folks at Phoenix, ARE, and several racers, I decided to go with the ARE system - better baffling, less foaming, better overall proven system. I know the LS7s had/have oiling issues as there have been several that have gone up in smoke.

As far as price, yep, the GS or Z06 system is probably a little cheaper, but again, is it better overall. No matter what, you're still going to pay a chunk ($1K) for the battery relocation hardware and install, so the sump and install was about 7K. It was worth it to me to get the better ARE system...and a monster oil cooler!!!! You just simply cannot get enough cooling to the LS3!!

HeavyRightFooT

Hi Guys, very interesting thread.

Couple questions : are these oiling issues a problem on stock z51 ls3 cars driven in HPDE's and track days on stock tires or Dot tires (like Kumho ecsta XS, Nitto 555rII and simmilar ) ?

Not being used to dry sump - vs wet sump discussion, what does a dry sump do that a good baffled pan cannot ?
How can a dry sump be of an use against blow-by ?

Any take on the line in the owners manual recommending to add a quart of oil before a track session ? isnt that a good way to make oil accumulation in the heads worth as well as bathing the crank in oil and having it sling it all over the cylinder walls ?
Is it just a way to insure there is always enough oil in the bottom of the pan during cornering ?

Sorry for the many questions but being the owner of an 08 z51 and a track day enthusiast I'm getting very concerned after readin this threat

Cheers,

O.

wtknght1

As long as you are running the stock tires with the stock suspension, you'll be OK...the engine should last. Definitely add 1 qt for HPDEs.

But, the engine was designed to handle 1.1 to 1.2 lateral Gs...maximum. So if you bolt on racing tires, turn left for any extended period of time over 1.2 Gs, the bearings will starve for oil - kaboom. The problem with the LS3 is turning left!

The dry sump creates a bit of a vacuum inside the engine and seals the rings better and keeps the oil from accumulating in the heads...so you don't get the superheated oil caused by blow-by...primarily at high rpms.

The baffled pan helps keep the engine alive (a little), but does nothing for the oil puking (into the intake), blow-by, and the ungodly high oil temps. The sump helps keep the oil from pooling in the heads, helps with the blow-by issue and with an enormous oil cooler, keeps the oil in the 230-280 range.