Pump upgrade

I currently have a Simpson powershot 4400 and as I plan for next year I am curious how can I tell what pumps would work with my machine. Currently, it is only 4gpm but I will have a buffer tank next year so I considered building a predator and pump combo or keeping my current engine and adding an 8 gpm pump on it. Is this feasible?

I know the horsepower is not that high compared to some others but I do still have 20 months on the warranty so I kind of figured it anything goes wrong, I can just reassemble it for warranty work. Also, if I had a good pump now and wanted a Honda down the road I could. I was looking to save as much as possible since I will be dropping a lot of money on other needs over the winter as I build my first skid and spending 4K on a prebuilt 8gpm is possible, I could use the money saved on marketing for 2024.

You can put an 8 on that engine, but it will not have enough pressure to clean concrete. A 5.5 is usually the max recommended for a 13HP.

I’m swapping a 4gpm to a 6 (very little concrete around here) on my GX390, and its going to cost me about $1,000 CAD (and I didn’t have to buy a gear drive so that saved me $450) when I could have bought a brand new 5.5 with a Honda for $2500. In hindsight I should have just bought new and kept the 4 as a backup or sold it.

Not saying you shouldn’t, but do the math on a pump + unloader + gear drive vs buying prebuilt and selling the machine you have.

Thanks. I had seen various formulas to calculate how much horsepower is needed but with different formulas I got different numbers so wasn’t sure which formula to rely on.

I could just sell it as well since it still has 20 months left on the warranty. I have seen 5.5 gpm around $2200 but I wasn’t sure if going from 4 to 5.5 would be worth it.

Well I’ll let you know when I find the right replacement bolts to put this pulley back on :sweat_smile:.

I work off a lot of wells so not planning for an 8 until I can switch trucks to something that can haul water.