Speed was hit by several withdrawals ahead of the Liberty Stadium win against Switzerland, with Danny Gabbidon, Robert Earnshaw, Andy King, Jack Collison, Joe Ledley, James Collins and Danny Collins all ruled out.
But all the remaining members of his original squad travelled to Sofia earlier on Monday as Wales go in search of what previously appeared an unlikely third place in Group G of Euro 2012 qualifying.
And while Speed would not commit to sticking with the XI who impressed against the Swiss, he admits it is good to have a settled group to choose from.
He said: "It is always a boost to have the same squad and the same personnel available to us, it's great for continuity going into this game and we are really looking forward to it.
"I am still early in my career and we have not had that many changes in personnel, but we want to try and keep a solid and settled squad and we have the people here to pick an unchanged team. Whether we do that or not remains to be seen."
Victory at the Vasil Levski Stadium will see the Dragons record back-to-back competitive wins for the first time since 2005, when they saw off Northern Ireland and Azerbaijan.
But the trip to eastern Europe will provide a stern test of the recent progress that Wales have made under Speed, particularly as this is their first fixture outside of Britain and Ireland in 12 months.
While Bulgaria sit bottom of the group and are currently under the control of caretaker boss Mihail Madanski following last month's sacking of Lothar Matthaus, Speed says showing they have the ability to cope with a challenging environment will be a big step in the right direction for his side.
"It is a test and a really good experience," he said. "We have had a good result and it would be easy to subconsciously relax, but not for me. Tomorrow is the hard bit.
"Bulgaria have a great history in football and a history of producing great players and it's the sort of place we need to come and get results if we are to improve, so this is a perfect test for us."
