Larger Trim Tabs or 4 Blade Props on a 320DA to get the bow down.

Discussion in 'General Discussion' started by MorichesBayBum, Apr 19, 2013.

  1. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    tabs2.jpg tabs1.jpg
     
  2. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    There bad pics its when first brought the boat.... Its all i can find right now... But not sure how to make something with this...
     
  3. Fly'n Family

    Fly'n Family Member

    528
    Sep 19, 2013
    TX / CO
    2002 Cruisers Yachts 3870
    2003 Boston Whaler Sport 130 w/40 hp Merc
    Twin 425hp Crusaders
    When I had my 370, it took a lot of power to get "over the hump" and on plane when I first bought it. Two things changed all of that. First, it had OEM props (98'). Props, like all other items, have significantly improved and the new props were an amazing change for the good. Second, I was fortunate to be retracting the anchor and the line broke away from the anchor. Went to an all chain rode and upsized one size on my anchor. Between the props and the added weight up front, it totally changed how the boat ran. It would jump (as much as a 370 can jump) out of the water and literally went right on plane......very little use of trim tabs anymore - only to finely tune things in. It was literally a different boat.

    Oh ya.....I was sure I needed 4 bladed props and Acme told me and convinced me to stick with a 3 blade....if I didn't like them they would swap them out for free. Damn glad I listened to the experts that actually make the prop.
     
  4. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    I went with all anchor chain last year.... I have about 200ft of chain in the locker with plenty of room but didn't want to add too much weight... Def worth it as in no one driving over my anchor line...and if they do sry...lol I do see a difference but still need a little more, I found a set of used 4 blades.... Gotta bring them my prop guy and see what he says...
     
  5. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    From the look of the pics i posted i think i might just have to add to them to make them longer (Bow to Stern)...But will that do anything or am i wasting my time?? Was thinking of maybe turning the sides down and just adding to under it and welding 3 sides..... Fig maybe they won't be digging in as much... I wonder why they mounted them like that crooked....
     
    Last edited: Jan 20, 2018
  6. mnm99

    mnm99 Active Member SILVER Sponsor

    Oct 2, 2015
    Long Island
    2004 340 SeaRay Sundancer
    Twin 8.1 Merc
    Wow , where do you boat again? Do you use any bottom paint on your rudders? And anything on your props? Anything on your trim tabs? First off next season Clean your props with acid and use prop coat on them and the shafts. They won't look like that. Clean your exhaust ports, trim tabs and rudders and coat them with a smooth coat of bottom paint. On another note, I had BS do my props also. This is the second year I had them tuned. I also was getting a bow up ride until I hit 30 mph, then it would smooth right out. So that was my goal. After bringing them to BS they re-pitched the props to what I said because of my WOT rpm. I gained 3 mph and was able to cruise at 3500 rpm at 30 mph and still hit my WOT. The boat flattened right out. This winter I had them add double cup and re-pitch. I know we have different setups, but from what your telling me ("I run WOT 5000 rpm at 34-35 mph with low fuel, no canvas.") I can see that you can get more out of those 350's. My friend had an 06 320 and he cruises with me at 28 mph at 3500 rpm. Hows the tune? I think by adding more tab your going to slow the boat down more. Call BS and see what they say. Also look at the difference in blade area with the 4 blades. Here is my bottom before the water. Looked pretty much the same when I pulled it in October. Bottom paint done.jpg Prop paint.jpg Prop paint 1.jpg Prop done.jpg
     
    Last edited: Jan 21, 2018
    M Prod likes this.
  7. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    That’s when I first brought the boat... It was a Florida boat in the water for 3 years that’s how it came out... Since then had the hole bottom re done and props scanned.... I can cruise at 27 mph bow high at 3900.... WOT 4400.. That’s the spec on the boat... Curious what the 4 blades and the trim tabs will do for me... Does your friend have vdrives??
     
  8. mnm99

    mnm99 Active Member SILVER Sponsor

    Oct 2, 2015
    Long Island
    2004 340 SeaRay Sundancer
    Twin 8.1 Merc
    Crap...LOL. Just saw it was from 2013...:rolleyes:. Well hope it helps someone in the future.....
     
  9. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    I am dealing with the problem now.... I just started the form up again?? Would love to hear from ur friend if he has vdrives and if so what’s his WOT??
     
  10. Woody

    Woody Well-Known Member PLATINUM Sponsor

    Nov 20, 2007
    N. Wisconsin/Lk Superior
    2005 420DA
    Cummins 6CTA8.3
    They have to be mounted that way so they touch the water.
    stern-6 - Copy.jpg
     
  11. SCORPIO

    SCORPIO Active Member SILVER Sponsor

    Apr 7, 2008
    Delaware
    1989 300 DA
    Twin 5.7 Merc Alpha I
    Last spring I installed longer chord from tabs on my 89 300 DA. These are the same width but deeper, as in extend further out from the transom effectively increasing area. These were also drop fin tabs, they help add lift as well. It was a couple hour DIY project and really improved both tab response and minimum planing speed. I got the tabs directly from Bennett. Ask Tabman in the Bennett forum here at CSR for his recommendations.
     
    Last edited: Jan 21, 2018
  12. mnm99

    mnm99 Active Member SILVER Sponsor

    Oct 2, 2015
    Long Island
    2004 340 SeaRay Sundancer
    Twin 8.1 Merc
    4400 should not be the spec on the 350's. The spec should be 4800 WOT. This is the sheet for 2004, but is the same.
    Yes my friend has V-Drives also. I'll ask him his WOT. He may not know , because he never opens it up. I do...lol..42 MPH at 4650 and had 8 people on board..Gotta love those big blocks. Mine is 4200-4600. The 350's rev a bit higher.
    http://www.searay.com/boat_graphics/electronic_brochure/Company1729/1C1_25_74DEIP4PY0Z.pdf
     
    Last edited: Jan 21, 2018
  13. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    Wish they made BB in the 320... So spec is at 4800 so they would have be pitched down so i would go even slower then at 3900 rpm.... So then my ass would def sit down even more...
     
  14. mnm99

    mnm99 Active Member SILVER Sponsor

    Oct 2, 2015
    Long Island
    2004 340 SeaRay Sundancer
    Twin 8.1 Merc
    Going down pitch would give you more RPM , but slower speeds.. There has to be something going on. Are you sure BS pitched them to the correct specs? Check the plugs, wires ,fuel filters ect.. Make sure your TACH is correct. All of that will make you loose power and RPM. It looks like they should be PROP, 18"X 19"X 3.55" "C" RH 1752166 4800 PROP, 18"X 19"X 3.55" "C" LH 1752165. Did they give you a sheet like mine? This shows I went up 1 pitch size and more cup. 21 after.jpg
     
  15. Siboatguy

    Siboatguy Member GOLD Sponsor

    163
    Mar 28, 2016
    Holmdel,NJ
    2005 Sea Ray 320 Sundancer
    Twins V-Drives
    2017 5.7 Mercruisers
    Don't know who BS is... I had a prop guy out here pitch them.... And just re powered the boat last year when i brought it... With everything new... Who is BS? maybe ill call them.
     
  16. mnm99

    mnm99 Active Member SILVER Sponsor

    Oct 2, 2015
    Long Island
    2004 340 SeaRay Sundancer
    Twin 8.1 Merc
    Bossler and Sweezey http://www.bosslerandsweezey.com/

    This was at 42 mph. I was running with a 39 Rinker with dual 496 HO with Bravo 3's and outran him.
     
    Last edited: Jan 21, 2018

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