since your engine is new, here is how i suggest you proceed: a) first 1/2
hour 30 weight dino oil; do not run at a constant rpm and shut down
immediately after-change oil and filter; b) first 500 miles - do not
exceed 50 mph and use dino 10W30; c) first 5-8000 miles - use either
10W30 or 20W50 dino. d) therafter switch to 5W50 synthetic.

the issue of leakage is relavant only if there was a problem to begin
with, synthetic will not cause a leak; but will flow more easily to areas
where there is one. solution? make sure your rocker covers are whole and
intact. -- 

advantages of synthetic? rank ordered:

better flow charcateristics especially at startup;
better heat transfer;
longer interval changes;

(claimed) higher pressure

have been using synth on a rebuild since 10000 miles, seems good
especially at startup in cold temps.
ggod luck - dc

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David Carment
School of International Affairs
Carleton University
Ottawa, Ontario
K1S 5B6
voice - (613) 788-2600-6662
fax - (613) 788-2889
Email address: dcarment@ccs.carleton.ca
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