“All show and no go” means someone (such as an athlete) or something (such as a race car) that looks good, but doesn’t have a winning performance. “All show—no go” was cited in print in March 1957. “Hot-rodders often say derisively of the customizers, ‘All show and no go’” was cited in October 1957. “In power-racing parlance there’s a commonly used phrase, ‘all show and no go.’ This refers to a boat cosmetically groomed to perfection that fails to win races” was cited in 1963.
 
“All hat and no cattle” is a similar expression that is used in Texas.
         
 
6 March 1957, Oakland (CA) Tribune, pg. 55, col. 1:
PCC ‘Varieties’
All Show—No Go
By RAY HAYWOOD
Sometimes you can take one encore too many, even when you are presenting one of athletics’ top comedy road shows.
 
3 October 1957, Lubbock (TX) Evening Journal, “Customizing, Hot-Rodding Of Cars Popular With Lubbock’s Teenagers” by Sheila Cline, pg. 10, col. 2:
Hot-rodders often say derisively of the customizers, “All show and no go.”
 
16 September 1962, Bridgeport (CT) Sunday Post, “Sibal Hits Out on Rail Report,” pg. 10, col. 6:
WESTON—The failure of the Kennedy administration to release the Whitman report on the New Haven railroad,  filed with :he Department of Commerce in July, was cited yesterday by Congressman Abner W. Sibal, R-Conn., as “a typical example of the New Frontier’s altitude of ‘all show, no go.’”
 
5 May 1963, The Sunday Star (Washington, DC), “Water Line” by Hank Bowman, pg. F-6, col. 1:
In power-racing parlance there’s a commonly used phrase, “all show and no go.” This refers to a boat cosmetically groomed to perfection that fails to win races. The rig looks terrific, but it lacks speed due to mediocrity of power plant and running surfaces or suffers from its helmsman’s light foot or weak throttle grip.
   
10 September 1963, Trenton (NJ) Evening Times, pg. 1, col. 4:
All Show And No Go
Gov. Wallace: Profile In Bombast
By James Marlow
WASHINGTON (AP)—Gov. George C. Wallace keeps Alabama’s temperature up but it’s an artificial fever.
 
In making a career of political defiance, he has become the master of the big noise and the empty gesture. When the going gets tough, he melts.
 
25 November 1969, Greensboro (NC) Record, “Check On Time Difficult” by Carlton Smith and Richard Putnam Pratt (NEA Service), pg. B6, col. 8:
So the buyer is forced to judge by outward appearances and the result has been a thriving business in lower-priced watches that are “all show and no go.”
   
Google Books
McGraw-Hill’s Dictionary of American Idioms and Phrasal Verbs
By Richard Spears
NewYork, NY: McGraw Hill Professional
2003
Pg. 11:
all show and no go Sl. equipped with good looks but lacking action or energy. (Used to describe someone or something that looks good but does not perform as promised.)
 
Urban Dictionary
All Show No Go
Phrase to identify what ricers do.
That Civic EX is all show no go
by pat August 10, 2003
 
Google Books
The Routledge Dictionary of Modern American Slang and Unconventional English
Edited by Tom Dalzell
New York, NY: Routledge
2009
Pg. 33:
All show and no go adjective
used for describing someone who cannot back appearances with action US 1978
 
Twitter
eRa Zayne 9mm
‏@eRa_Zayne
Toyota 86/Subaru BRZ’s are all show and no go, saw one get beaten by a Nissan X-Trail in a straight line drag smh
2:08 AM - 17 Mar 2015