most sportsman racers.
The biggest mistake a sportsman racer can make, however, is to try to duplicate the performance characteristics of a dry-sump using a wet-sump system.
This simply can't be done without sacrificing reliability.
Many sportsman racers look to Pro Stock for inspiration.
In some instances, the technology that is used in Pro Stock is applicable to other classes - but lubrication system design is not one of them.
Pro Stock engines are universally equipped with dry-sump oiling systems.
The luxury of an external oil storage tank allows a Pro Stock engine builder to use an oil pan that is the size of a small refrigerator and to install a vacuum pump that sucks the air out of the crankcase like a tornado.
Pro Stock racers use lightweight lubricants and restrict the oil flow to the absolute minimum.
I couldn't recommend these tactics in good conscience to any bracket or Super eliminator racer.
Using a large-volume Pro Stock-style oil pan with a full-length sump is an invitation to disaster with a wet-sump oil system.
I insist on using an oil pan with a rear sump on every Super Series bracket racing big-block we build |
at
Reher-Morrison Racing Engine - even if the engine will be installed in a dragster with plenty of room between the frame rails for a full-length sump.
Here's
why: When a car accelerates at one "g," the
oil stands up in the rear of the pan at a 45-degree
angle. At two "g's" acceleration, the
oil is plastered to the back of the pan at a 66-degree
angle. The same thing happens when the car
decelerates, except the oil piles up at the front of the
pan, and the oil pump pickup sucks air. With a
full-length sump, there is little hope of keeping the
oil pump pickup covered.
The low-viscosity oil that is commonly used in drag
racing engines today has the consistency of kerosene
when the engine is at operating temperature. You
can see for yourself what happens to the oil in a
full-length wet-sump pan by filling it with four quarts
of water and rocking the pan forward and backward.
Tilt the pan at a 66-degree angle to simulate what
happens during a two "g" launch and
deceleration. Even baffles and trap doors can't
keep the oil pump pickup submerged under hard
acceleration and deceleration.
I strongly
advocate using a solid windage tray to shield the oil
pump in any wet-sump |
