24 Superboat How fast??

[76Stingray]

I think i am way off on top end speed. I have a 24 Superboat, she's an old one, 1976 so obviously pre stepbottom, and probably pretty heavy. But i thought with a 235 X-flow she should run about 58 with the right prop. I've heard of 24's w/ 200 merc 60 mph, w/225 merc 62 mph, so i figured with the OMC 235 bout 58 mph....... maybe i have heard wrong with the mercs, maybe i figured wrong, or maybe I am just way off with props so far. I am only getting 47 - 48 mph and thats working to get there. Any info, input, prop suggestions..........Help me please cause 48 just aint fast enough!!!!!
CB
24 Superboat "TIME OUT"

[donmac]

I think the omc is about 100lbs. heavier than the mercs. does sound a little slow what rpm are you twistin. I may be wrong on the weights but i thought mercs were about 350. omc about 450

[Steve2ManyBoats]

Merc 2.0 and 2.4 V6's weigh about 350. OMC Crossflow V-6's weigh around 370, so they're in spitting distance.

Regarding your speed expectation, as I recall back in the day (way back, like the late 70's), the Suffolk County Police clam cops ran 235 crossflows on 21' Challengers. That's the mold that became the Superboat 21. They ran about 60-64 mph. Just about the same speed as a 16 superboat with an inline 6 Merc 150, which made for some interesting chases with clam poachers. I'm not sure the same power - 235 crossflow - will get you 62, or even 58 on a Superboat 24, but it should get you more than 48.

Have you gone through the usuall stuff - link and synch, testing max timing at 5,000 rpm, right prop? As for props, look into the trophy and raker. Both have lots of bow lift, which you'll need. I happen to have 2 extra brand-new vented Rakers (20" and 22" pitch) if you're interested.

Also, did you check offshoreonly.com? They have a very active Superboat forum which some factory guys frequent.

Good luck.

Steve2ManyBoats.

[76Stingray]

Thanks guys...... goona check out offshoreonly. I tried a 23 Raker and the boat wouldnt plane at all currently running a 4 blade 13 1/2 23P Shooter planes pretty good and RPM's are a little low....tach not working (trying to get that fixed ASAP) But can hear its NOT screamin. Sync n link are good, have to check timing again. Would like to try a 24 chopper.

[Dave S]

Old boaters went faster than..... no GPS.:p

[76Stingray]

very true.......think maybe i need to scrape together some cash for a couple of 2.4's....maybe someday

[Steve2ManyBoats]

That boat's too heavy for a chopper. Stick with a thru hub prop. Drop an inch in pitch and see what happens

[76Stingray]

need to try a 22 or 23 Trophy sound about right?

[76Stingray]

is the Trophy prop considered a "surface piercing" prop?

[Superbender]

sound like it just may not be makin power,sorry should be goin way faster

[lightspeed]

My 86 24 Went 68.9 With A 03 225 Merc Swinging a 25 Trophy Bash runs 74+ Anyday Of The week And Best Of 78.9

[76Stingray]

yes but remember this is a TIRED 235....but it should still run betterthan 48. I need to keep experimenting with differant props.....and get a tach, duh!