Mu child is under  an evaluation request. I believe the 60d ends today or tomorrow. School just sent me a request for parent input. I need more time than a few hours to write a thoughtful response to be included. Is my timeline impacted by providing input after day 60?

I'm not in PA, but it's on the school to complete evaluations within their required timeframe. Have you already consented to the evals? Has the school done evals, had a meeting with you to discuss eval results, and are they now creating the IEP? There's a section in the IEP for parent input/concerns.

The special education teacher/coordinator/supervisor leading the process for you should be able to explain timelines, but you can always check you state Dept. of Ed. website to confirm the timelines you are told are accurate. Let them know that you need more than a day to submit parent input. Also see Lisa's post at https://adayinourshoes.com/parent-concerns-on-the-iep-parent-letter-of-attachment/ for writing impactful parent input letters.

Parent input can be submitted at ANY time.

Parent input goes into the IEP.  The eval report is what's due in 60 days - not the IEP.  They have 30 days from eval report to IEP meeting (if the student qualifies for an IEP).  There is a booklet of PA timelines on PATTAN.  This is the link to get to it:  https://www.pattan.net/Publications/Special-Education-Timelines

You have a bit of time to provide your input and have it in the IEP.

School didn't seem to do the right testing without my input so the evaluation report they issued on day 60 (which says no need for IEP)  doesn't address the concerns fully.  Even though I handed them a private evaluation which recommended they do an OT evaluation, the OT evaluation school did had nothing to do with the concerns presented in the private report.

Have you talked with the school's OT? The school evals are supposed to cover all areas of concern, however, the school doesn't have to agree to recommendations in private evals. If I understand correctly, you've already paid for an independent eval and submitted that report to the district, correct? If so, they are supposed to "consider" the private report.