im relatively new to the boating world and im going to be running a plastic prop with a diameter of about an inch with 2 fins on a traxxas blast with a velineon system on 6 cells, do you see anything problems i might have, what about trim, the water will be completely flat and its going to be speed runs only, should i have it trimmed up or down or in the middle? (again im new to all this)

Are you running stock hardware or upgrade parts? Post some pic of your boat including pics of the transom (rear end). Where did you get this prop? Is it a stock prop off the Traxxas boats? 2 fins, do you mean 2 bladed prop or 2 turn fins??

its completely stock besides the velineon system and the prop is bigger than the prop it came with, but its still made by traxxas

Firstly, that Velineon motor is on the hot side for this setup. So we don't know the diameter and pitch of the prop. Firstly do make sure the prop is the proper turning prop for your boat. Looking at the back (transom) the prop rotation in relation to the leading edge should turn counter clockwise. I would run the boat for a minute and bring the boat back in. Check the temp of the motor and esc. If it is still cool to the touch, run it for another minute. But run it full throttle, never run half or quarter throttle. Things specially the motor and esc will heat up quicky. And heat is a great way to kill your esc/motor. If it is still okay to touch then try running it again for a few more minutes. No longer than 5 minutes. Check again. If it is warm to the touch then you're okay. I noticed that your motor has cooling coils, which is okay. But is your esc water cooled as well?? Remember when running boats, your motor and esc needs to be water cooled as they are locked in the hull with no air coming in to cool anything. And I don't recommend running a any other motor in boats other than ones made for marine use. Unless you have some experience. I would strongly suggest figuring out the diameter of the prop. If the boat is running a little hot, you will need to prop down specially running a motor that is 3000 + KV. The higher the Kv the less torque it produces and the smaller prop you need to run.

thx for the info ill see if i can rig up some watercooling for the esc

Word of caution: The times above are hard times. It's easy to stay out for 2 minutes if you feel the boat is running good. Frist time out- excited- that's when most ESC's die. You might want to run like one lap and bring it back the first time. Baby steps until you know how thick the ice is.

If you run this on 2s you will be fine..
possibly you could prop up even more once you check temps and make sure they are good with the prop you have now..
lots of power in this little hull, very cool!