> -----Original Message-----
> From: owner-land-speed@autox.team.net
> [mailto:owner-land-speed@autox.team.net]On Behalf Of 3liter
> Sent: Tuesday, February 10, 2004 1:47 AM
> To: LSR submissions
> Subject: Oil restrictors in a SBC
>
>
> Dave:
>
> I usually follow right along with you, but this time... Can you explain
> further?
>
> "If they do not rotate it can be caused by the timing gear being
> machined to
> the wrong dimension".
> How does that stop lifter rotation? Is the gear too thick or thin pushing
> the cam too far in either direction?
Yes it might change the relationship of the taper on the lobe with the crown
on the lifeter.
>
>
> "Vacuum pump on crankcase set too high".
> With vent holes throughout the engine, the pressure is sure to equilibrate
> without any delta p. How does high vacuum stop lifter rotation?
>
Everything that is done to reduce windage, either oil pan scavenge system or
vac pump will affect the oiling of cam and piston pins
>
> "Look in Stef's catalog and see if they also sell spray bars to add oil to
> the top end to cool the valve springs.."
> O.K, they don't sell spray bars...
>
I was curios if the same place was telling you to use a product to limit oil
to the top end and then buy another to put it back.
>
> "Then ask yourself how important the restrictors are. They were originally
> used to keep more oil in the oil pan if the sump was small and the rpm
> high".
> So don't run restrictors and flood the springs, yes/no?
Restrictors and some other items like them are an effort to convert a
passenger car oiling system to something more suitable for racing. This is
also an effort to use something for a situation it was never designed to
handle. A SBC for the most part has the same oiling system designed in 1954
for the 265 and 100 hp. They did add a full flow filter a few years later so
maybe the date ought to be 1958 and 140 hp.. The HP levels they see today
are so far from the original design as to be ridiculous.. All the little
tricks are to help the stock system work better for limited duration events.
The answer is to buy a real oiling system IE Dry sump and use a block with
the appropriate size oil feeds and drains. With a dry sump spray bars will
never hurt anything. With a stock wet sump it will probably steal too much
oil from the mains and rods.
Dave
-Elon
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