England now meet the French in Brive next Friday night with a first ever Grand Slam on offer and Davies said: "It's a huge challenge going to France and Brive is one of the hotbeds of rugby. But it's something we will relish and it's the first opportunity England have had to go for the Grand Slam so that will spur us on."
Davies, a half-time replacement for Adrian Jarvis paid tribute to his team-mates who held on despite a late Welsh challenge that included centre Lee Thomas missing an injury-time penalty and winger James Wellwood knocking on as he stretched to score in the corner.
"The defence at the end won the game," said Jarvis. "It was a difficult second half but we stuck in there and got the result. We were seven points down at half-time but Jon Callard's message was not to panic."
Wales were ahead 19-12 at the break thanks to tries from No 8 Gavin Quinnell - the youngest of the Welsh rugby dynasty - scrum-half Richard Rees and capt James Merriman of Gloucester. They led despite having Ian Evans sin-binned in the 20th minute for taking a man out off the ball at a restart.
England had opened the scoring in the seventh minute with the first of Ben Skirving's tries, the Saracens No 8 powering over from a line-out on both occasions. Quinnell filled
Skirving's try sandwich before Rees, Merriman and Thomas' boot put Wales clear.
Callard's half-time talk had an immediate impact with centre Andy Reay taking the ball five metres out as England pressed the Welsh line and stretching out to score. Davies' conversion levelled at 19-19.
Wales had flanker Richard Dale stretched off in the 57th minute and while Thomas missed a penalty for not releasing, Davies made no mistake from 40 metres to leave England unbeaten at the top of the table.
England Under-21 manager Peter Drewett said: "This is what Test rugby is all about, whether you can keep your defence and discipline when you are under pressure and we did that for the last five minutes."
And he is looking forward to the trip to France, saying: "If the players and management can't get excited about going to Brive with the chance of a Grand Slam then we shouldn't be involved. England have never won a Grand Slam at this level and we are very excited about next week."
England: J Clarke (Northampton); M Garvey (Gloucester), C Bell (NEC Harlequins), A Reay (NEC Harlequins), U Monye (NEC Harlequins); A Jarvis (NEC Harlequins rep B Davies Gloucester h-t), C Stuart-Smith (Leeds, capt); N Wood (Gloucester), R Hawkins (Bath), M Guess (Gloucester rep T Warren Worcester h-t), J Percival (Worcester), C Day (Sale Sharks, temp rep T Parker, NEC Harlequins 3-7mins), B Russell (Saracens), W Skinner (Leicester Tigers rep T Parker 46), B Skirving (Saracens rep L Narraway Gloucester 39). Replacements (not used): S Friswell (Leicester Tigers), R Wigglesworth (Sale Sharks), J Bailey (Bristol Shoguns).
Scorers: Tries - Skirving 2; Reay; Con - Jarvis, Davies; Pen - Davies.
Wales: M Nuthall (Celtic Warriors); J Wellwood (Wasps), G Evans (Llanelli), L Thomas (Pontypridd), F Brillante (Cardiff); N McLeod (Cardiff Blues), R Rees (Swansea rep James Ireland Cross Keys 78); J Yapp (Blues), W Kay (Newcastle), C Griffiths (Neath-Swansea Ospreys rep I George Newport 69), J Mills (Bath), I Evans (Pontypridd), R Dale (Newport rep Tom Brown Hartpury College 56), J Merriman (capt, Gloucester), G Quinnell (Llanelli). Replacements (not used): Adam Yelland (Scarlets), C Martenko (Pontypridd), M Jones (Neath), L Andrews (Cardiff).
Sin-binned: I Evans 20-30
Scorers: Tries - Quinnell, Rees, Merriman; Cons - Thomas 2.
Referee: M Changleng (SRU)