After losing their last three Magners League games, the Scarlets forwards have come under criticism for being out-muscled, especially in their Boxing Day defeat to the Ospreys, but Easterby says his pack will test the Irish.
He said: "I think those criticisms have been made about us for a few years and I don't think we need any extra motivation for this weekend. If we win, we are in the quarter-finals of Europe and no side needs any more motivation than that.
"Our front-five have been far better than anything we have had for a number of seasons, there is no issue there, we don't feel there is any outside pressure either. We know what to expect on Saturday and we are ready for the challenge."
Along with Wales internationals Dafydd James, Vernon Cooper and Stephen Jones, the 31-year-old is one of the survivors from the side which won 29-6 at Ravenhill in 1999 and expects a thunderous match.
The Scarlets are unbeaten in the Heineken Cup with four wins after their stunning 41-34 win at Toulouse when they came back from 24-3 down, but Easterby does not expect a similar free-flowing affair.
He said: "They are a formidable team when they play well, especially at Ravenhill and very hard to beat at home.
"There are a few of us in the Scarlets side who have won there in the Heineken Cup and we know what to expect: a vocal crowd and a tough 80 minutes. There won't be much left in the tank at the end of 80 minutes.
"We have beaten them at home, only just, and lost away to them in the Magners League. It's a tough place to go, it's different to somewhere like Toulouse. There may not be as many points scored on the day but it will be just as physical and there will be just as an intensive atmosphere."
Easterby will be up against his Ireland rival for the No.6 shirt, Neil Best, but like any good diplomat Easterby will put the team before any national aspirations.
"As long as I play well and make some good decisions, those are the most important thing for the team. If we win, then I will be more than happy," he said. "I just have to concentrate on my job and let things take care of themselves, I can't afford to think about anything apart from that."
Scarlets: M Stoddart, D James, R King, G Evans, M Jones, S Jones, D Peel, I Thomas, M Rees, D Manu, A Jones, S MacLeod, S Easterby (c), G Thomas, A Popham
Replacements: J Davies, K Owens, V Cooper, D Jones, C Stuart-Smith, C Thomas, M Watkins
Ulster: M Bartholomeusz, T Bowe, A Trimble, P Steinmetz, P McKenzie, P Wallace, K Campbell, B Young, R Best, S Best (c), J Harrison, M McCullough, N Best, K Dawson, R Wilson
Replacements: P Shields, J Fitzpatrick, T Barker, R Caldwell, N McMillen, P Marshall, I Boss, A Larkin, B Cunningham, K Maggs