Ok here is where I am at, I have a spa that has a century laser motor on it hp is 3.0-.38 spl and 10.5/2.6 amps and I want to replace the motor.

Can you run a higher amp motor with the same wet end, lets say I wanted a 12/4.4 amp motor which is for a 4hp but wanted to use the 3hp wet end with it will this work?

Also the spa has 29 jets and came originally with a 5hp jet power pack per advertisement the original owner downsized because it was cheaper.

I want to add a second pump and my spa has this option, now the second pump I want for one big jet and am thinking of using the old pump for it and get a 5hp new pump to run all of the little jets.

Do I have to worry about to much pressure on the lines here? Dont want to make leaks.

Any help with this is much appreciated

It depends on if the controller can handle the extra amps. BUT, if you use the same wet end, including the same IMPELLER, a 100 HP motor wont move any more water than what the impeller is rated for.

Lol... that's a joke - You really need to ignore this - manufacturers lie big time.

The only difference between a 15 amp motor and a 10 amp motor with no load is basically almost nothing.

Start up current only.

It takes a few more amps to spin up a heavier armature - but on the fuse-blowing richter scale - it's defintely nbd.

So yes (as Dr Spa indicated), you could put as much as a 15+ amp labeled motor on your existing wet end and be just fine. The label only tells you what the motor is CAPABLE of sustaining over time - it does NOT tell you real horsepower.

Real horsepower measurement requires work to be done.

Moral of the story - replace with equal to or better than your existing motor voltage/amperage and you'll be just fine and dandy.