Pump is shot. Shopping for replacement...

[Scrapple]

Would this one work? Looks like the ends come off and can be threaded into the inlet.

[BigDave]

Inlet of the filter? I don't know if it would thread directly on - you'd probably need a threaded version of that valve and a nipple.
I like ball valves for throttling. PoolDoc recommends gate valves because they're easier to operate.
Hint: When you winterize, set the ball valves to 45 degrees - water is trapped in the valve body when it's open or closed.

[mas985]

When using a throttling valve, it doesn't matter where you put it. The flow rate reduction is the same. However, you are probably better off putting it after the filter so it doesn't collect debris.

But another option is to put some DE into the filter. That will add restriction and reduce flow and improve filtering. At least this way you get something for the reduce flow rate. To get 35 GPM, you want to add enough to raise your clean filter pressure by at least 4 PSI and that should do it.

Also, flow rates on pump labels are meaningless. Those are usually run out or maximum flow rates and not what you typically get on pool plumbing.

[BigDave]

@mas985: Clever idea, DE for throttling. I suppose it would clog up real quick though.

[mas985]

Only if the pool was dirty but isn't that point.

[BigDave]

I just thought of another reason to place a throttle valve between the pump and filter: If there's too much flow on backwash, much sand will be lost.

[mas985]

If that will be an issue, it should be an issue with the existing pump as well. But a good point.