In the bloodthirsty American League East, it is not the champions of New York, per Boston or Milwaukee, who are most likely to stay on the pennant trail down to September's final days.

Despite all the massive free-agent spending done in those cities, it is the Baltimore Orioles - baseball's up-for-sale designated paupers - who now seem the most buoyant club in baseball's most storm-tossed division.

That is not to say that the Birds are the best team in the mighty East - though they have the best record in all baseball: 38-21.

Nor is it a senseless prediction that they will win - though the traditionally skeptical, self-doubting O's (even Jim Palmer) finally believe that they can.

Obviously, any team, can sink under its unpredictable burden of 162-game misfortune. And if the Orioles entered the last fortnight of the season knotted with either the Yankees or Red Sox, the Birds would have vastly less pennant angst experience.

One shocking point, however, is clear. It will take more bad breaks, more unforeseen injuries, to knock Baltimore off course than any other team in the East, and probably in all of baseball.

The truth about the Orioles' suddenly discovered strength and depth is seen not in obscure statistics and esoteric arguments but in the most basic facts of the game: starting pitching and power hitting.

The Orioles, still a largely unknown and widely pitied aggregation, have so much pitching that their feathers have barely been ruffled by delicate Jim Palmer's frequent missed starts and Scott McGregor's two winless months.

What other-team could get virtually no production from a 15-game winner and spotty performances from its ace, yet win 34 of 47 games?

If Palmer and McGregor were entirely removed from the Baltimore roster - and Earl Weaver has no such plan - the rotation of Dennis Marthinez, Mike Flanagan, Sammy Stewart and Steve Stone might still be one of the game's best. No single injury can derail the O's staff.

"Nobody can approach the Orioles' pitching," says Milwaukee Manager George Bamberger. "They got a prospect (Dave Ford) in the minors who's never been scored on in the majors (in 15 innings) and he can't make the club."

As for clout, Bird power is so deep that they barely missed the bat of the AL's No. 3 slugger in '78 - Doug DeCinces - when he missed nearly a month of 1979 with a back injury.

The Yankees and Brewers find themselves six and seven games, respectively, behind the O's in the loss column and point mournfully at their injuries. True, but the Orioles have built their .644 mark with an above-average number of miseries.

Manager Weaver has the happiest of all possible answers to the insistent, yet fundamental, pennant-race question: What does your team have to do to win it all?

"Nothing special," responds Weaver with an impish grin.

What he means, and reiterates constantly, is that he needs no superhuman seasons from his stars - just routine excellence. From his bench and numerous blossoming younger players, he asks only creditable performances and modest improvement.

"The last couple of years, the Orioles were good enough to stay in contention," says Kansas City Manager Whitey Herzog. "Now they're good enough to win."

Those 97-and 90-win seasons were built on a shoestring and Weaver's guile. They were his proof of near-genius.

Now, Weaver has the horses - big ones, and useful ponies, too.

In the bottom of the ninth, needing three runs to pull out a victory, Weaver needed three lefty pinch hitters. So he called on two of the best - Pat Kelly and John Lowenstein, then got the game-winning hit from a third - Terry Crowley. That's depth.

When a team wins by one run thanks to two homers from its 25th man, Bennie Ayala, and a game-winning pitch hit from its 24th, "Crow" Crowley, then it has a right to dream.

Even more concrete reasons exist for Oriole optimism.

"Every one of our seasons for several years seem to be the same," says Captain Mark Belanger, who will miss three weeks with a broken finger, but, naturally, has a hot-bat replacement in Kiko Garcia.

"We have trouble early in the year when lots of teams are still fresh and enthusiastic. Then, the second and third times we play them, you can just see the fire go out of them. Our pitching wears the down . . . every season.

"We we've needed is a strong start, because we always feel that the end of the season is ours."

The Birds even look at defeat with enthusiasm these days, at least in restrospect. "That 3-6 road trip (before their currently completed 6-1 home stand) actually helped us," Belanger ventured. "It could have been 1-8 if you saw it. Our pitchers had to work 50 innings in three days, but they survived it.

Those Royals, with their three consecutive division flas, are suitably impressed.

"No team in baseball can match their four starters, says Herzog, "and their long relief has improved to go with an excellent bullpen. Can Tippy Martinez get out the left-handed hitters that Earl wants him to . . . that's the only question."

Herrzog continues, "Their power is close to the very best. Their two catchers can catch, even if they don't hit much.

"If they lack anything, it's overall team speed, especially in the outfield. They don't steal much or scare you on the bases. But with their power, I'm not sure Earl wants 'em running wild."

Certainly, the Orioles have more liabilities than that. Palmer becomes increasingly finicky about his health with age and will never jeopardize his chances for 300 career wins for a paltry thing like a pennant.He'll call in sick plenty, until September.

Every team would like a little chrome-polishing - a better righty pinch hitter than Ayala, a less flighty utility infielder than Billy Smith, a more consistent southpaw in the pen than Tippy Martinez.

But with Gary Roenicks slugging in left field, with Tim Stoddard emerging as a bullpen monster, with a dozen other positive signs, the Orioles can, for the moment, sit back and sum up their blessings with two words.

What do we need to win? "Nothing special."