In an effort to silence political critics, Attorney General Griffin B. Bell yesterday gave full Watergate-style procecuting powers to the "special counsel" he appointed to investigate bank loans to the Carter family warefouse business.

Paul J. Curran, the former U.S. attorney from New Yorke who was named special counsel in the case Tuesday, will now have the same authority given Watergate special prosecutors, Bell said at a news conference announcing Curran's charter.

Bell had stopped short of giving Curran full powers Tuesday, saying that any decisions to seek indictments would have to be approved by Philip B. Heymann, head of the department's Criminal Division.

Though Heymann said then that he would overrule Curran only if the special councsel's recommendation were "unconscionable," Republicans in Congress immediately criticized the lack of independence.

Bell insisted yesterday that he wasn't backing off from his previous position because of political pressure. But he said the milit on Curran's authority was "just a red herring. It was something to talk about and write about and argue on the senate floor about. It didn't amount to nothing so I just decided to take it out.

"I'm more interested to reject comparisons with Watergate of the inquiry into bank loans to President Carter's family peanut warehouse business. He said "special counsel" was a better term than "special prosecutor" because there's a "vast difference" between this inquiry and the Watergate scandal.

"In Watergate there was a great deal of evidence of crimes which had occured in the government. So they used the term, 'special prosecutor.' We don't have a situation like that. What we need is a fact-finding," the attorney general said.

Bell said he deicded late Thursday night to drop the limit on Curran's powers. Heymann said the agreed with the decision and was reday to argue for the change Himself.

"I felt we had done everything an administration could do to bring out the truth about a set of facts. I felt we were doidng it. And the focus of the attack was a provision that had no practical impact," Heymann said.

Curran was informed of the added authority and was "surprisingly indifferent," Heymann said. Curran could not be reached for comment.

Bell said he boubted that the reversal in the department's position would silence the largely partisan criticism that greeted Tuesday announcement of Curran's selection.

"It I was on that side I'd probably keep going as long as I could, 'till I was out of breath," Bell said.

Initial response from Republican leaders was mixed. Sen. Bob Dole (R-Kan.), a member of the Senate Judiciary Committee minority that had called for a true special prosecutor, said Bell's decision was "in the best interest of the nation of the presidnet."

But Sen. Strom Thurmond (R-S. C.), ranking minority member of the committee, said though an aide that he still thought a court-appointed special prosecutor was in order.

The charter Bell made public yesterday gives Curran a mandate to investigate and prosecute an offenses arising from "financial transactions between the Carter warehouse and the National Bank of Georgia or any other financial institution, from related financial or business transactions or from the use of the loan proceeds."

In pursuing the investigation, Curran, like Wastergate special prosecutors before him, can determine for himself "whether and to what extent he will consult with the attorney general." And Bell argeed in the charter to "not countermand or interfere with the special counsel's decisions or actions."

The special counsel is needed, Bell said Tuesday, because the president and his brother and mother owned the warehouse, which got millions of dollars in loans from the bank controlled by former Office of Mangement and Budget director Bert Lance.

The ware house investigation is a recent spinoff of the broader investigation of Lance's finanical dealings while head of the National Bank of Georgia. A Preliminary FBI investigation found possible biolations of banking laws in the warehouse loans, and raised the question of whether records concerning the loan may have been manipulated.

Curran's job will include trying to determine whether any of the warehouse loan money was diverted, even temporarily, to the Carter presidential campaign. The White House has denied this posibility, but Charles Kirbo, trustee of President Carter's financial holdings, has refused to open the warehouse books, despite repeated requests from reporters.

Bell declined yesterday to say exactly how broad Curran's mandate is, but he emphasized, "I have not given the special counsel a roving commission to go about the country investigating any and al things."

The carter is a blend of the authority given the Watergate prosecutor and of the provisions for a "special prosecutor" under the new Ethics in Government Law.

Curran can be fired by Bell "for extraordinary impropriety, physical disability, mental incapacity or any other condition that substantially impairs" the performance of his duty, the charter said. This tracks the new stature.

At the end or his investigation, Curran is to send a final report to Bell and Congress, under terms of the charter.

Bell acknowledged yesterday that he might have been wise to delay announcment of Curran's appointment until the requried charter was reday too.

A Bell aide said that, in hindsight, it would have been better to give Curran full powers from the beginning, "That would have taken away the field before they started playindg political footabll," he said.