Dr G

Guys:- Is anyone here running a dry sump system on their thirdgen?

Do you guys think it would be worth the hassle and the (very) high cost?

Here is a link to How Stuff Works comparison between wet and dry sump systems:-
http://auto.howstuffworks.com/question331.htm
And another:-
http://auto.howstuffworks.com/framed...e.com/info.htm

Here is a link to one of the threads I came across on this site whilst searching for more info:-

Wet/Dry sump
https://www.thirdgen.org/techbb2/sho...light=dry+sump

I look forwards to hearing your opinions!

RB83L69

What is this car going to be used for?

Dr G

RB83L69:- This car is going to be a purely weekend street and occasional strip/track car. Set-up for road-racing/autocross rather than being optimised for the drag strip.

I would appreciate some comments about the principles of the system in general though. I'm aware that for most peoples cars it would be considered 'overkill', and that it would not represent a good dollar to horsepower ratio.

RB83L69

From your description, probably not a very worthwhile expenditure of money.

The operation is pretty simple; there are a number of sections of the pump for scavenging oil out of the engine, usually 3 (each valve cover and the pan), and one pressure section. The scavengers all return the oil through a cooler to a tank. The pressure section draws oil fromt he tank and sends it into the motor.

The disadvantages are weight, expense, and complexity. The advantages are extra oil capacity, lower crank windage, and less tendency for all the oil to accumulate in the VCs (the hottest place in the motor) at high RPMs. It's not a "horsepower" issue, but rather one of insuring survival.

Unless you plan on operating the engine at above 6000 RPM for extended periods of time (oval track usually), it isn't worth it. Most casual street and "road racing" and autocross doesn't justify the expense and extra hardware.

Rembrandt

All you really need is a good baffled wet sump pan.


Another advantage for a real hardcore car is that a dry sump system allows you to place the engine lower, but unless you have custom engine and transmission mounts made, you won't be doing that. For road and oval racing that lowers the center of gravity a little and allows a little more hood clearance.

Some serious engines use dry sump systems as well as vacuum pumps to lower the pressure in the crankcase. This reduces some crankcase pumping loss and aero drag, but more importantly maintains a higher pressure difference between the compression rings and the crankcase, which can improve ring seal and dynamic compression. Also with a better sealing ring set, you can use thinner, lower tension rings for less friction, more power. But that's all custom stuff, lots of work for ~25hp on a 650hp engine.

Read these articles if you're really curious:

http://www.rehermorrison.com/techTalk/21.htm

http://www.rehermorrison.com/techTalk/24.htm

Dr G

RB83L69 and Rembrandt:- Thanks for the comments guys!

Thanks for the links to the articles - they made good reading!