Fresh water Vs salt

[ZekesterbluH3]

How does running fresh water compare to salt as far as top speed? is it neglible or is there a difference, working a night shift, just pondering : )

[yeller]

Funny that I should see a thread like this today. I just got back from running up the river to the local lake and was enjoying how much better my boat rides in the fresh compared to the salt. Lately I've been doing more salt water boating. As I would view it, the theory should be that salt is faster because technically the boat would be more buoyant and should have less drag.

I find that my boat seems to handle better in fresh water and therefore I can run it harder and faster than in salt. A friend of mine (and usual passenger) brought it up on his own the other day, that he prefers the ride of the boat in fresh water. He said the boat feels safer and more stable.

I would think it would depend on the type of boat. For my boat, I can always run faster in fresh water. Doesn't mean my boat couldn't run faster in salt.....just that I can't run it hard enough to find out. For my boat, I think it has more to do with the type of waves. I run in a protected salt water area with a lot of yachts that kick up nasty wakes. Combined with the natural slow rollers of the ocean...........well........my boat just doesn't like it. A 35 footer or larger would have no problems. In the fresh water I boat in, the rouge wakes aren't as large and the waves are closer together which lets me run much harder....and therefore, faster.







IF you could ever run identical conditions on the same day......I'll say salt would be faster.

Am I right?????.......am I right??????.......:confused:

[BUIZILLA]

actually Yeller, I notice the same thing on my Critter, perhaps even more so than you do, since it has a big block and the driver/passengers sit so far back... it is a NOTICEABLE difference for me, so much so that I try and switch props for either occasion...

[BlownCrewCab]

Usually you calculate 10% more slip for fresh water. I Remember runnig a tripple outboard cat at Lake X, when we found the right props for the lake they took them off and handed us boxes of the same prop with less pitch since we where headed to sarasota to run in the salt.


Oh. and Yeller, Yes, You are Right!!!!

[Conquistador_del_mar]

The rule of thumb that I was always told was that you run about 7% faster in the ocean with the denser salt water content which makes for better prop bite and hull lifting. My two cents, Bill

[BigGrizzly]

We had a thread on this several years ago. As everybody knows I run several Gps on my Criterion and have 800 hours driving it, and have taken it to every event I have attended in the last 8 years except one. Yes It handles slightly different in salt. As for speed, I go the same averaged top speed everywhere. Now with the blower in the box it is almost always altitude compensating. People tell you that salt is denser so the boat floats higher, true. Now the denser water produces more drag on the lower unit weather a standard or shorty, plus the prop drags more. So the they actually rule them self out. Now on a jet drive there is a noticeable difference, increase in speed. As a kid I had this discussion with my Dad. To prove a point we took out 16 from Point pleasant NJ to Trenton NJ to run on the Delaware river. We did the measured mile thing-no GPS then. There was no difference in speed to be noted except a tenth or 2 mph difference. On a cat or big boat or twin out drives there may be a difference as B crew cab stated. BTW as you also know I can change props but normally don't. Just for your information my Dad was correct.