lowcountry

iTrader: (1)

I have searched the forum and haven't quite found the answer I am looking for.













I will be getting an LS7 crate engine from an aftermarket company, still researching - Mast, Texas Speed, etc. Something similar to the Mast 427 SS 650 HP rated one. This will be a street car for now with maybe a few engine upgrades as I become more familiar with LS engines.






Most offer a choice between dry and wet sump oiling. The dry sump would be the GM/LS7 version...I would like to get a few opinions. With cost aside, what would be your choice?





thanks

tadams72

Unless you are planning to make a pretty radical road track car, there is no need for a dry sump. Wet sump oiling is preferred for most applications for ease/cost vs benefit. Dry sump is great if you are moving to high corner g loads, sustained 7000+ rpm. Even if you find yourself needing to move to a dry sump application you should not go with the LS7 setup. It's actually considered to be more of a hybrid setup. For a truly effective dry sump system you'll want to go with a company like AVAID and pumps designed with multiple scavenging points.

lowcountry

iTrader: (1)

Thanks for your reply. Taking "ease/cost" out of the equation, I was wondering if there was a benefit for my application. As far as dry sump oiling goes in general, I agree the LS7 system is not the best choice for road racing, etc. But, GM chose to install them on a "street" vehicle for a reason...guess I tend to wonder why.

Millenium Z06

Because of what tadams72 mentioned, road racing applications which these cars are used for by some owners. There was issues in previous gens with oil starvation in high g applications, I'd guess GM thought this was the solution but they half assed it.
Theres also a HP benefit with dry sump, in that it reduces the amount of oil caught up in crank shaft windage.

93Polo

iTrader: (5)

If you are planning HPDE time, I would go dry sump. If not a wet will be fine.

panic

Better ground clearance vs. a deep conventional pan with similar windage control.

IMHO don't bother.

gnx7

iTrader: (28)

Improved racing pan baffle and be done with it.

Otherwise if you have a serious track car on slicks do Aviad, ARE, Dailey billet, etc. That's an easy $3-4k to set up in parts.

KCS

iTrader: (20)

Even though the LS7 is a hybrid/half *** dry sump, it's still packaged better than a true dry sump. No external pump and pulley with a belt that could slip or come off. It's crank driven so as long as the crank is turning, you are getting oil.

It's still better than a wet sump system too. One of the LS engine's major flaws is how badly it aerates the oil. Pulling the oil into a seperate reservoir helps in keeping the crank from whipping up the oil as badly and the internal design of the reservoir helps deaerate the oil. It also helps to have the large oil capacity as well.

lowcountry

iTrader: (1)

Thanks. This makes sense to me - sort of along the lines I was thinking, especially about having a large oil capacity. But I didn't want to trust my own thinking - not having much LS experience. I also have a C&S Racing radiator with provisions for oil cooling that I plan to use with the dry or wet sump...


All of the replies are great info. Thanks. I guess I'm still undecided - will need to think more about this over the next few weeks...

lowcountry

iTrader: (1)

Another quick question. Hopefully someone can answer this here without me starting another thread.


On the LS7 style dry sump, what keeps the oil in the external tank from emptying into the engine after sitting for prolonged periods? The pump? I'm guessing it is a positive displacement gear pump?

SHovV

iTrader: (1)

You answered your own question. The oil pump.

It sucks from the pan and pumps to the external tank, then sucks from the external tankandpumps throughout the enginewhere oil drains back to the pan,starting the process over.

John B

iTrader: (10)

Depends on your HP objectives as well.....I was after every last ounce of power so I went dry sump for my LS7...you can only imagine how pissed I'd be if I had to settle for 694 RWHP instead of being able to crack the magic 700 mark at 704 RWHP because I went wet sump!