diff --git a/builder/googlecompute/builder.go b/builder/googlecompute/builder.go
index 1cb79f2a7..83557eff8 100644
--- a/builder/googlecompute/builder.go
+++ b/builder/googlecompute/builder.go
@@ -23,12 +23,11 @@ type Builder struct {
 
 // Prepare processes the build configuration parameters.
 func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
-	c, warnings, errs := NewConfig(raws...)
+	c, warnings, errs := NewConfig(TemplateFuncs, raws...)
 	if errs != nil {
 		return warnings, errs
 	}
 	b.config = c
-
 	return warnings, nil
 }
 
diff --git a/builder/googlecompute/config.go b/builder/googlecompute/config.go
index 020ec9ab8..d4f37a569 100644
--- a/builder/googlecompute/config.go
+++ b/builder/googlecompute/config.go
@@ -63,8 +63,9 @@ type Config struct {
 	ctx                interpolate.Context
 }
 
-func NewConfig(raws ...interface{}) (*Config, []string, error) {
+func NewConfig(funcMap map[string]interface{}, raws ...interface{}) (*Config, []string, error) {
 	c := new(Config)
+	c.ctx.Funcs = funcMap
 	err := config.Decode(c, &config.DecodeOpts{
 		Interpolate:        true,
 		InterpolateContext: &c.ctx,
diff --git a/builder/googlecompute/config_test.go b/builder/googlecompute/config_test.go
index 551692b29..cd36ba619 100644
--- a/builder/googlecompute/config_test.go
+++ b/builder/googlecompute/config_test.go
@@ -181,7 +181,7 @@ func TestConfigPrepare(t *testing.T) {
 			raw[tc.Key] = tc.Value
 		}
 
-		_, warns, errs := NewConfig(raw)
+		_, warns, errs := NewConfig(TemplateFuncs, raw)
 
 		if tc.Err {
 			testConfigErr(t, warns, errs, tc.Key)
@@ -240,7 +240,7 @@ func TestConfigPrepareAccelerator(t *testing.T) {
 			}
 		}
 
-		_, warns, errs := NewConfig(raw)
+		_, warns, errs := NewConfig(TemplateFuncs, raw)
 
 		if tc.Err {
 			testConfigErr(t, warns, errs, strings.TrimRight(errStr, ", "))
@@ -269,7 +269,7 @@ func TestConfigDefaults(t *testing.T) {
 	for _, tc := range cases {
 		raw := testConfig(t)
 
-		c, warns, errs := NewConfig(raw)
+		c, warns, errs := NewConfig(TemplateFuncs, raw)
 		testConfigOk(t, warns, errs)
 
 		actual := tc.Read(c)
@@ -280,7 +280,7 @@ func TestConfigDefaults(t *testing.T) {
 }
 
 func TestImageName(t *testing.T) {
-	c, _, _ := NewConfig(testConfig(t))
+	c, _, _ := NewConfig(TemplateFuncs, testConfig(t))
 	if !strings.HasPrefix(c.ImageName, "packer-") {
 		t.Fatalf("ImageName should have 'packer-' prefix, found %s", c.ImageName)
 	}
@@ -290,7 +290,7 @@ func TestImageName(t *testing.T) {
 }
 
 func TestRegion(t *testing.T) {
-	c, _, _ := NewConfig(testConfig(t))
+	c, _, _ := NewConfig(TemplateFuncs, testConfig(t))
 	if c.Region != "us-east1" {
 		t.Fatalf("Region should be 'us-east1' given Zone of 'us-east1-a', but is %s", c.Region)
 	}
@@ -314,7 +314,7 @@ func testConfig(t *testing.T) map[string]interface{} {
 }
 
 func testConfigStruct(t *testing.T) *Config {
-	c, warns, errs := NewConfig(testConfig(t))
+	c, warns, errs := NewConfig(TemplateFuncs, testConfig(t))
 	if len(warns) > 0 {
 		t.Fatalf("bad: %#v", len(warns))
 	}
diff --git a/builder/googlecompute/template_funcs.go b/builder/googlecompute/template_funcs.go
index 0831cf410..52ae7d121 100644
--- a/builder/googlecompute/template_funcs.go
+++ b/builder/googlecompute/template_funcs.go
@@ -1,7 +1,6 @@
 package googlecompute
 
 import (
-	"regexp"
 	"strings"
 	"text/template"
 )
@@ -19,8 +18,7 @@ func isalphanumeric(b byte) bool {
 // Clean up image name by replacing invalid characters with "-"
 // truncate up to 63 length, convert to a lower case
 func templateCleanImageName(s string) string {
-	re := regexp.MustCompile(`^[a-z][-a-z0-9]{0,61}[a-z0-9]$`)
-	if re.MatchString(s) {
+	if reImageFamily.MatchString(s) {
 		return s
 	}
 	b := []byte(strings.ToLower(s))