That's what Comp Cams says, but it's actually an "it depends".
273 solid lifter pushrods are 7.50. I'm pretty sure that the 340 6 pack adj. rocker hydraulic pushrods are around 7.23. But also "it depends" on block decking, head milling and # of valve jobs, which increases valve stem height. All of these creates a need for shorter pushrods. Unless I'm missing something, I always felt that the Comp Cams spec was some sort of compromise. Ideally, find the length you need with an adjustable pushrod and compare it to a known length or send it off to a pushrod manufacturer.