The Carter administration and defense contractors are making an all-out effort to save the CX transport project, Chairman Richard H. Ichord (D-Mo.) of the House Armed Services research and development subcommittee said yesterday.

Ichord predicted it will be "a very close vote" in the full committee this week when it decides whether to uphold the subcommittee's refusal last Thursday to provide any money for the CX.

President Carter requested $80.7 million in fiscal 1981 funds to start the CX, which Ichord said would end up costing $12 billion for a fleet of planes little different from the C5A transports already flying.

Ichord said he and other members of the committee are being heavily lobbied by Defense Secretary Harold Brown, Air Force leaders and defense contractors to authorize money for the CX.

Like the C5A, the CX would carry the heavy equipment for the Army. But Ichord said the C5A can carry only one Army XM1 tank at a time and the CX, under some of the designs being considered, will not be able to do any better.

His subcommittee, the chairman continued, rejected the CX on an 8-to-3 vote because the Air Force did not make the case for it. The plane was "too highly political," Ichord said, "something that sounds good following Iran but wouldn't have done us any good there."

Those on the 11-member subcommittee who voted to authorize the CX money, Ichord said, were Rep. Larry McDonald (D-Ga.), G. William Whitehurst (R-Va.) and Donald J. Mitchell (R-N.Y.).

Ichord said he will press the full committee to transfer CX money to ships for the Rapid Deployment Force.