trapp

I tracked my c6 Z51 for a few years with last year using a accusump...I had alot of problems with the accusump so I dumped the car (09) and bought a Grandsport (11). I now have a dry-sump and plan to run R6's at some point. Is the stock dry-sump solid protection....or should I do any upgrades?

wtknght1

The stock DS is certainly not perfect and does have a few minor flaws (foaming), but it'll protect your engine and you can feel free to run whatever tires you want.

trapp

I heard that they have changed a few things over the years...(increased the amount of oil reserve etc..) I don't know if it is true???

Anyway thanks for the feedback....

quickc6

GM went fome 8 qt to 10 qt oil tank.

Katech_Zach

The stock dry sump system is fine for it's intended purpose-a 505hp car with stock brakes and stock tires. When you start modifying to increase power, braking, handling and grip, you can exceed the limitations of the stock system. If you are serious about racing on slicks, you should consider upgrading the dry sump system.

froggy47

Hi Jason,

Let's say it's a given that many/most of us run DOT R tires or slicks and often do brake upgrades.

Let's leave engine mods out of the equation.

So what went wrong with the motors after the LS6, which for the most part holds up damn well with it's stock oiling system + a qt.

Seems like GM had it right & just lost their (engineering) minds with LS2/3/7 or am I all wet?

At some point I'll move on from my 04Z but (from what I read and talk with friends) I don't care much for any of the newer stock LS motors.

Do you guys sell a "package" that is just oiling upgrade, without having to buy a built motor? Maybe you should if not. I have to figure you would get it right.

Thanks.

travisnd

Good question... nobody's ever given an answer to what they changed LS2 and up that makes them have so many issues. Everyone assumes it's something to do with the internal oil galleys, but It'd be nice to know for sure.

Can anything be done to the block before install to mitigate the issue? I mean for most of us a $5000 dry sump system to protect a $4000 motor isn't in the cards.

trackboss

One thing to consider is that if you have oiling problems it shouldn't be a concern to upgrade the oil system even if it costs more than the motor is worth. Reason being is that a failure could result in you oiling the track down and losing your whole car as well as causing a whole lot of wreckage behind you.

travisnd

Again.... some of us like our LS6s. Our motors that will run for years w/o any fancy stuff. GM screwed it up. What'd they change?

My race car has 120,xxx miles on the motor and it made 361 rwhp last summer with a K&N drop in filter, 10% underdriven ATI Superdamper, and a road race safe tune... that's it.

I run it 1 quart over full with the large DRM oil cooler kit and a high volume LS4 oil pump... no Accusump, no drysump, etc. etc.

You say we shold buy one because we might lose our motor and wreck the car.... well I might wreck the car for a bunch of reasons... does that mean I should go ahead and buy a spare race car to keep in the garage ready to go?

froggy47

I could see that GM would have problems across the engine line if ALL the POST LS6 motors were turbocharged, supercharged, all overhead cams etc, but damn, they are BASICALLY the same design, yes?

travisnd

Yes they're all in the LS engine family. LS2 just got a 4.0" bore and the LS3 I think just a smidge more.... stroke is the same on all I think. The LS7 is bore and stroke.

LS2 uses LS6 heads and a cam similar to a 2001 Z06 cam. The LS3 got a new style head more similar to the LS7 head.

They must have changed something in the internal oil passages of the block casting... no idea why or what.

trapp

Make me understand this: The stock dry-sump system has a limitation on the peak G's or on the duration of the G's? I plan to run hoosier r6 on the GS with DTC pads. What mods do I have to make to the stock system? If I hit say 1.5 G instead of 1.1 with street tires why will that make a difference on the stock sump?

wtknght1

None. There are plenty of guys in T1 and STO running the stock DS system and hitting higher Gs (for longer) and they are just fine.

NemesisC5

Subscribed....

96CollectorSport

My theory - for what it's worth - has to do with the increased size of the cylinder bores. The LS6 block with a 3.900" bore was/is the "ideal" LS block, then the LS2 came out with it's 4" bore (with the same heads as the LS6) and people started having issues I think Buttermore blew up 4 before switching to a dry sump. Then came the LS7 with it's 4.125" bore and GM immediately put a ds on it - kinda makes you wonder.
And finally comes the LS3 with a bore a tick over 4 and you see even more issues than the LS2 - I think the issues of the LS3 are 2 part - 1 the larger bore and #2 the cylinder heads, with the larger runners (especially the the large intake runners) the oil just hangs out in the cylinder heads and can't drain back down with the larger cylinder bore.
Again this is my theory but it just kind of makes sence.

96CollectorSport

I know that Jerry runs his LS7 with the Aviad baffel and oil pan mod and a Katech pump. Those few mods have seemed to work for his STO LS7 and I think it would be tough for most cars here to keep up with him.

Pumba

GM has been scrambling since the LS7 and LS3 hit the road race courses. They are still working on increased pump capacity for their oil pumps.

AVIAID makes a conversion kit that improves the oiling system for LS7 and LS3 engines with a dry sump - http://aviaid.com/pdfs/153-boltin_dr...6_corvette.pdf

There are also better oil pumps available for the LS family of engines - http://forums.corvetteforum.com/auto...pump-data.html


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Katech_Zach

What's different about the LS2/LS3 engine? In the context that you are speaking, fundamentally nothing. I think it has to do with the car. The car has more grip, more power, and better braking than ever before. If the pickup tube is hanging in the air it doesn't matter how good the oil pump is, it's going to starve the engine.

We sell ARE Stage 3 dry sump systems for our street/track day guys and we use Dailey systems for the more hardcore engines.


Duration. That's the fundamental reason for a dry sump system. Keep the oil in a tank off to the side so you can carry more oil without huge oil pans. If you exceed the cornering level to where the pickup tube is starved for oil, you have until you empty the dry sump tank to starve the pressure pump. There are two ways to improve this. One, design a better oil pan that can handle higher g-forces without starving the pickup. Or two, increase the capacity of the tank so when you do starve the pickup you have a longer amount of time before you run the tank empty. Race engines with proper dry sump systems add a third factor to the improvement. Adding a better pump so you can actually pull a vacuum on the pan.

travisnd

Sorry but that doesn't pan out in real world club level racing. Thost of us with LS6s have no issues running the cars full out with wet-sumps. LS2/LS3s all of a sudden big problems.

The C6 chassis isn't fundamentally different. You put the same power motor in a C5Z vs. C6 and they'll have the same capabilities.

Something changed in the LS2/LS3 somewhere.

Katech_Zach

The contact patch and the braking capacity of the C6 was the difference I was speaking of.