P13 models came stock with sewups. 700c was not available in 1973, one would have to look at a dealer order sheet to see if clinchers were available as an option, as the frame would be different. You could probably get 27" wheels to fit, but the brakes might be too long. Paramounts could be custom made for an extra charge (and a long wait during the bike boom). People who wanted clinchers would generally buy a P10 or P15 which came with 27" clinchers. I recall that custom builders in the Albany, NY area were pushing 650b wheels instead of 27" because better quality touring tires were available. Things sure have changed.
Steve Barner, Bolton, Vermont
> Date: Sun, 28 Jul 2002 10:47:59 -0700
> Subject: Re: [CR]P13 Paramount
> From: Pete Imandt <imandt@earthlink.net>
> To: <classicrendezvous@bikelist.org>
>
> I'm new to this period-correct propensity -- wouldn't period-correct '73
> P-13 clincher rims be 27-inchers? Is that a road you want to go down?
> During it's renovation (I fear I can't call it a restoration) in the late
> 70's, we put long reach "Schwinn Approved" center pulls on the '68 P-15,
and
> it's happy with 700c's. It may not be period-correct; however, tire
> availability is not a problem.
>
> Pete Imandt
> Ramona CA