Are you sure you’re getting 4,000 psi AND 4gpm? The formula I’ve read on here to calculate the needed engine HP to achieve those specs is psi x gpm / 1,100.
It’s possible if you were running a nozzle for those specs but not actually producing those numbers, you’d have better results using the lower psi nozzles because they’re the correct size for your machine.
I don’t know what they have down under, but he probably had a 13hp. If so, you can have pressure or gpm, but you can’t have both at those specs. Kudos for experimenting and finding out what worked best for you.
Yep, spot on - it’s a GX390 
Try getting a dual lance wand, you can still have your 40 degree tip on there to get the fan you like, but then you can crack open the valve and have low pressure. The pump is a fixed displacement pump so you’ll always have the same flow regardless of pressure. But i swear by my dual lance wand.
Fixed
yes, a fixed displacement pump is positive displacment pump as compared to a open chambered pump like a car’s water pump. Basic hydraulics.
Oh man you likey the hydraulics we need to talk about my new rig! I need massive hydraulic flow
Why do a lot of people here feel like they are so great and need to stroke their ego? Grow up.
Likely because most things could be interpreted incorrectly through text
Are you under the impression everyone is out to hurt you in some way?
yeah, i usually sit at home hidden under blankets fearing someone will say something mean. That’s why i like to stay in my safe space. 
Do you have room for one more? We can talk hydraulics if that would make you feel more comfortable about it lol
I have the same machine. Choke the ball valve about 2/3rds open and it will work great.
That would be cute
Dont forget to stroke your ego.
Never
Oh no no no
He was complimenting you @mwpws not stroking his ego. He was basically stroking yours.
Damn. Somebody’s touchy.
Also, if there’s going to be any stroking going on around here it needs to go through me first for approval. Then you can stroke to your heart’s content. I can’t stand non-approved stroking. It sticks in my craw.
