I have a 97 fountain 24cs with a 502 mpi. I have a hydromotive quad 4 24p prop and I only get 4700 rpm and 64 mph gps at wot. This boat is supposed to do 70-75 mph with a quad 4 26p prop. Could weight be that big of an issue? I have quite a bit of stereo equipment and 4 batteries and my girlfriend is with me when i test and with a full tank of gas.

Weight can make a huge difference. The lighter the boat, the more difference it makes. Your boat is listed at 4100lbs dry. If you add 300lbs worth of stereo/batteries and full of fuel (350lbs), the GF (130lbs???)you have just increased the weight of the boat by almost 20%. Where the weight is in the boat can also make a big difference.

So if I shed all that weight you think I can gain 6+ mph top speed?

Probably close to it. I lose about 4 mph off my top speed with full fuel and 4 people compared to just me and 1/4 tanks. Air temp and humidity will also make a difference.

A 24CS with a stock 502 will run right about 74 MPH. That is of course under optimum conditions. (And I should add that the ones I've driven are pretty evil right at the limit.) The weight you've added will make a difference, but I'm kind of doubting that big of a difference - especially since you're running a smaller prop too. Sounds to me like you might be down on power. Have you checked simple stuff like plugs, plug wires, tune up, etc?

Just something else to check. The 24CS came with a bow mounted ballast tank. Did you possibly fill that bad boy by mistake?

Yeah I've checked all that. If I can get my rpms up I'll go to a higher pitch prop. So I'll take that weight out and hopefully get up there. If I drop around 600 pounds of weight I wonder if I can gain 300 rpm?

600 pounds is a lot of weight in a smaller boat. Then there's where it sits in the boat too. The further forward, the worse it gets for top end.

Just out of curiosity, where did you find space in a 24CS for all that stuff? They just barely have room for what comes with them from the factory! I hate working under the hatch on those bad boys.

There is quite a bit of room up in the bow where all my stereo equipment sits then i got two batteries under the back seat and two batteries in the engine compartment. You think i can gain that much rpm if I lose 600 pounds?

Only one way to find out! Like I said, 600 pounds is a lot in that hull.

my 96 24cs ran 70mph @ 5000rpm with a 26P 4 blade bravo. full tanks and the wife.