road draft to pcv

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rustynutgarage - 27 Sep 2006 01:32 GMT

I'm putting together a early 289, customer has purchased the aluminum
finned valley cover and vlv covers. The cover is set up for a road
draft tube but we'd like to go to a pcv valve.
Anybody ever done this and if so can you clue me in on the details. The
original valley covers have a baffle the aftermarket alumn does not.
I'm a bit concerned that with out the baffle it may try to pull oil
thru the pcv valve. Also were mounting the partial flow filter on the
firewall and I need a good place to return the oil without running
hoses all the way to the timeing cover and dumping it there. My idea
was to put a fitting in the valley cover for both the return and the
pcv valve, but again with the oil return that close to an unbaffled PCV
fitting it might use oil. Any ideas are appreciated.
Thanks
Russ

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Mike - 27 Sep 2006 09:58 GMT

The vent system for the "R" engines is worth imitating. The idea was to
use the air flow to help move oil back to the pan. It's explained in the
SAE paper on the Avanti. I think the idea came from the Lark V8's that were
prepped for compact stock car racing, (Holman & Moody?).
The air goes in the valve covers, down the push rod holes to the valley,
to the crankcase, and out a baffled stack on the side of the oil pan. The
PCV draws air at low speeds, and the air intake for the carb at higher
speeds. If you make a stack, the idea is to make big passages, to slow the
air flow down, so oil can drop out. You also want it to change direction a
few times. Baffles work better than stuffing.
Head dowels with slightly larger oil return holes, were part of the oil
return improvement; but I think they were one of the changes that came with
the full flow blocks.
It's worth noting that the Granatelli's just added breathers. I doubt the
system works as intended on R3 & R4 engines.
It would be best to return oil from the filter directly to the pan; but
you already have a hole in the valley cover.
Mike M.

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Grumpy AuContraire - 27 Sep 2006 15:33 GMT

> I'm putting together a early 289, customer has purchased the aluminum
> finned valley cover and vlv covers. The cover is set up for a road
[quoted text clipped - 10 lines]
> Thanks
> Russ

I have road draft tubes on all my Studes. IMNSHO, Studebakers (other
than R series) do not have adequate ventilation when using a PCV. I
would leave it alone or maybe chrome plate the tube if you're into
"shiny" stuff..

JT

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Mike - 27 Sep 2006 19:57 GMT

JT wrote -

> I have road draft tubes on all my Studes. IMNSHO, Studebakers (other
> than R series) do not have adequate ventilation when using a PCV.

Interesting thought. Funny though that one of the same size PCV valves
can control a much larger cubic inch and crank case volume....AT a
higher RPM, (big block Fords, Chevys and Chryslers)...but can't keep up
with a little Stude engine?
Sumthins wrong here.

If it can't keep up and the system (crank case) pressure builds to the
point of leaks....the cause of the pressure needs to be found and
corrected!

Wether its from leaking rings or leaking head gaskets, (the only two
places extra pressure can come from), they need to be fixed.

A road draft tube is just a small breather tube that may or may not be
effected by the wind roaring past as you are driving down the street at
50mph.

For me...a "properly" designed PCV system...OR breathers on each rocker
cover (NOT both), will work fine. A PCV valve in the valley cover and
"one" inlet location, like a rocker cover and into the air cleaner is
the other way to go.

The engine I'm building for my Conestoga....will have a single large
breather in each rocker cover AND an "R" series breather tube from the
oil pan. I've also changed the way air moves around inside the crank
case a little. The NASCAR guys found some things, in that "all" areas
(or chambers) need to have as open a passage as possible so as to not
be able to store built up pressure. All areas need to be able to
evacuate pressure as quickly as possibe. My block has a few holes not
originally designed in!

The air actually moving the oil around.........not unless you've got a
drysump system working. The oil mist "will" move around where ever air
is present (!)...but slow moving air will not driect oil on it's own.

Mike

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Grumpy AuContraire - 27 Sep 2006 20:42 GMT

Au contraire... The extra ventilation features found on R series
engines solves the problem. Studebaker just never got around to fixing
it on the standard engines.

The only other provision for ventilation on PCV valve equipped standard
engines are the two oil filler caps and hardly anyone keeps them cleaned.

JT

> JT wrote -
> > I have road draft tubes on all my Studes. IMNSHO, Studebakers (other
[quoted text clipped - 36 lines]
>
> Mike

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