diff --git a/scripts/test-bifrost.sh b/scripts/test-bifrost.sh
index 66e126bcc..6eaf238f5 100755
--- a/scripts/test-bifrost.sh
+++ b/scripts/test-bifrost.sh
@@ -24,7 +24,6 @@ ZUUL_BRANCH=${ZUUL_BRANCH:-}
 # placed in the configuration drive. The "build image" test does not
 # use cirros.
 
-VM_MEMORY_SIZE="3072"
 # NOTE(rpittau) we can't use kvm in CI
 VM_DOMAIN_TYPE=qemu
 export VM_DISK_CACHE="unsafe"
@@ -70,14 +69,12 @@ fi
 
 # Adjust options for DHCP, VM, or Keystone tests
 if [ ${USE_DHCP} = "true" ]; then
-    VM_MEMORY_SIZE="1024"
     ENABLE_INSPECTOR=false
     INSPECT_NODES=false
     TEST_VM_NUM_NODES=3
     INVENTORY_DHCP=true
     INVENTORY_DHCP_STATIC_IP=true
     WRITE_INTERFACES_FILE=false
-    VM_DISK=12
 elif [ ${BUILD_IMAGE} = "true" ]; then
     USE_CIRROS=false
     TESTING_USER=root
@@ -118,9 +115,9 @@ ${ANSIBLE} -vvvv \
        test-bifrost-create-vm.yaml \
        -e ansible_python_interpreter="${ANSIBLE_PYTHON_INTERP}" \
        -e test_vm_num_nodes=${TEST_VM_NUM_NODES} \
-       -e test_vm_memory_size=${VM_MEMORY_SIZE} \
+       -e test_vm_memory_size=${VM_MEMORY_SIZE:-512} \
        -e test_vm_domain_type=${VM_DOMAIN_TYPE} \
-       -e test_vm_disk_gib=${VM_DISK:-10} \
+       -e test_vm_disk_gib=${VM_DISK:-5} \
        -e baremetal_json_file=${BAREMETAL_DATA_FILE} \
        -e enable_venv=${ENABLE_VENV} \
        -e bifrost_venv_dir=${VENV} \