I recently got a 1986 35ft Webbcraft Concord. I am new to performance boat (if you can call this one) and need some advice. It has twin 454 mags and 3 blade 21p props. I am having trouble getting max speed b/c it porpuses a lot and I am getting about 58mph at 3400rpms on each tach. I don't know if I could get much faster but 3400rpms sounds low. I was told maybe 4 blade props might help. Anyone know anything about these boats and what I could do to help it.

Thanks

All of these 35 Webbcrafts porpoise. It's a hull issue. Do you have tabs?

Did you buy the one that was in the OSO classifieds for a long time? I believe it said 'MECH WARRIOR' down the side.....? I've always liked the look of those Webbcraft Concords. Good luck and enjoy it.

Yes, I have tabs. I trim them down to control it, but I lose speed. Didn't know if there was any other way to fix it.

No. I got one from a repo auction. Got it very cheap. The paint looks great, but it needs some interior work. It's a good boat though. I am thinking of selling it and moving up. I might put it on here for like $17k.

You need a lot less prop pitch. Those engines need to spin at 5000rpms at WOT.

Those numbers figure out to a negative slip value. Something isn't right there. My ScarabIII with the same setup does the exact same numbers but at 5000rpm. Maybe you tachs are off? you realy need to spin the chit out of a 21 to hit 58 . . . . or hook me up with a set of those props


one other thing i may have the original sales brochure for that boat. I will see if i can dig it out.

your numbers don't add up......i have a 35 webb concorde w/454 alpha drives w/3 blade 21p props. mine will turn 4800/5000 rpms wot, with tabs down and drives up with no porpusing 58 MPH/GPS. have had it 62 mph/gps under near perfect conditons. what drives do you have? i can't imagine having to go down on the prop.....but guess a 19 would bring your rpm's up to where they should be.......there's alot here that could be..........you have got a solid boat. you will enjoy it......

Thanks to everyone for your advice.

I have alpha 1 drives. There is a good chance my tachs are off. I did buy the boat in a repo sale. I will check those first. If they are right I will try a smaller pitch. If they are broken I guess I'll fix them and see what I have. It does seem a little off to go 58mph at such low rpm's

i'd also check that speedometer.....get a gps unit....that'll tell you your actual speed......you may be a bit surprised.......you should be fine with those 21p props......if you go with a lower pitch prop...be careful not to over rev those 454's.....they don't like it.......trust me on that.......