Hydrofoil or trim tabs?

[calvinman]

Hello to Iboat forum users,

I have been lurking here for the last few weeks, and have learned allot , and as a first time boat owner, I need all the insight I can get.

We picked up a 2006 Glastron SX-175 with a 4.3 Volvo Penta drive unit this spring, and we are loving it.

The boat is a little stern heavy, and when towing two or three tubes around sometimes have trouble planning under 20 mph. At first I thought I would get a lower pitch prop and a hydrofoil to help remedy this (I would like a little more hole shot/acceleration also).

The boat will do 56 mph at 4800 rpm(unconfirmed) so I think going down in pitch is maybe a bad idea.

After more reading of the forums, I am thinking maybe I should go with trim tabs over a hydrofoil.

Funds are limited this year, so I think I will just pick up another stock 14-1/4 x 23 prop to have as a spare,(price sure is right at $90 US) and maybe some trim tabs. Next year I would like to pick up a stainless prop that would give more performance off the line.

I would appreciate any thoughts or suggestions from my more experienced fellow boaters.
d

 

[Reel Poor]

Re: Hydrofoil or trim tabs?

If your already running a 23 pitch prop and hole shot is suffering with a heavy load, get a 21 pitch, that will dramatically increase your hole shot capability (faster out of the hole). Be sure to watch WOT use because with the lower pitch the engine will now over rev at WOT, just pull the throttle back a little so you don't over rev the engine and everything will be fine.

Save your money for the Smart Tabs. Don't buy the hydrofoil.

 

[steelespike]

Re: Hydrofoil or trim tabs?

If I'm reading it right You are just having trouble staying on plane around 20 mph.Something like smart tabs will solve that easily and improve hole shot as well.Do a little saerch you will find lots of smart tab info.

 

[ziggy]

Re: Hydrofoil or trim tabs?

all a hydrofoil did for me on my last boat was break my ventelation plate. more than once......i aint havein any hydorfoil on my new(er) boat......if had issues, i'd think about some smart tabs.....aint read hardly nobody that don't like them for issues like you discribe.....
i'm kinda outa line here as i don't know the facts real well on props. but how abouts a 21 SS. that may keep the rpms a little lower as the SS prop won't flex as much as the aluminium and still give ya the better hole shot. ya'd still have to watch the rpms, but ya should do that anyways. seems like ya could trim lower too with the 21 and that would help keep them down too. might loose a bit of top end. it depends on what ya want. like ya said, some of ea. perhaps. a work prop, and a speed prop...........

 

[tashasdaddy]

Re: Hydrofoil or trim tabs?

going to the 21 will help with the hole shot, and you want loose but maybe 2-3 mph. smart tabs are the way to go. to me the hydrofoil says, i have a problem, and i'm too cheap to fix it correctly. besides they are UGLY!!

i have a 23' Chris Craft deckboat. the difference between a 19 and 21 pitch is the difference between a lazy dog and a scared cat.

 

[calvinman]

Re: Hydrofoil or trim tabs?

Thanks for all the info people, Yes I think trim tabs are the way to go, I hope they will fit without interfering with the ladder, I will have to go out to where my boat is stored and do some measurements. Does anyone know how much the smart tabs stick out behind the transom?

Going down in pitch also sounds like what I should do, I usually cruise at 35 mph, and can’t take the boat over 45 without wifey getting exited anyway. I think the SS will have to wait, I’ll just pick up aluminium for this year. I like “Scared Cats” LOL Tashasdaddy! You da Man!

Ziggy, sorry to hear about your bad experience with Hydrofoils. My buddy swears by them, but drives his boat very conservatively, while I tend to bounce my boat around allot more, which would put a lot of stress on the “whale tail” I would think.

 

[ziggy]

Re: Hydrofoil or trim tabs?

the difference between a 19 and 21 pitch is the difference between a lazy dog and a scared cat.

that's the way i see it on my boat too. though my boat is only 19'. i didn't even know i had a hole shot with a 21 on my boat.

sorry to hear about your bad experience with Hydrofoils

no big deal at all. i'm just letting you know what my expereice has been with them things. and a broke vent. plate is one of them. that's why were here i think. to let ea. other in on our expereices, good or bad. i also think about the load that is put on the drive when your doing yer holeshot with a hydrofoil. bow high, stern low. the drive must be at a good 45% angle to the water and yer takeing off hard. that seems like it would put a lot of stress on yer drive. more than the oem had intended. yes. it will get ya on plane faster and be able to hold it at a lower speed. but to me the benifits don't outweigh the down side of them. especially when there is an alternitive.........sounds like yer on the right track to me. smart tabs and down a pitch size. ya probably will be closer to that scared cat i would think.

[qutoe]I think the SS will have to wait, I’ll just pick up aluminium for this year[/quote]

if bread is a factor in yer decison for yer new prop. check out yer local dealer. mine has used props on hand. many of them. i got my aluminim 19 pitch for a hundie, used. it's a mercruiser prop and was in fine shape. didn't save that much. but they let me try it before buying it. which is what i expect from my dealer.(premium price but with service) i knew it was right after a trial run. and that seemed better to me that trial and error for 150-175ish for new. not knowing if it would do what i wanted or not.......

 

[QC]

Re: Hydrofoil or trim tabs?

Friends don't let friends use hydrofoils . . .

Edit: I think I just found yet another signature.

 

[Tail_Gunner]

Re: Hydrofoil or trim tabs?

Trim tabs will get you up and on plane that is a given, however a 19 is probably a underkill.I've just gone thourgh this with a 4.3 efi volvo and a 19' boat.

Id go and post this up in prop forums and see what they reply back, going from a 19p to a 20p 4blade made the wellcraft a different boat. Not only does it have more hole grunt and a stronger midrange along with a 5mph increase, it also rides much high on the water making it a much smoother ride on any chop.

The wellcraft is 500lbs heavier and has a 6" wider beam (bigger boat) yet has the same engine and probably drive combo, so yes your glasstron is probably stern heavy (mine was) and if i remeber correctly it also has a 20 degree v. Volvo has also lifted the stern drive unit up a bit (does your cav plate ride above the keel) which will let it take advantage of some better tech prop mfg's use now and probably a good 4blade stern lifter in a 20p would be right in order. It's worth your time to go see the pro's a small investment can go along way's.

 

[ziggy]

Re: Hydrofoil or trim tabs?

i'll try this quote thing again,

Friends don't let friends use hydrofoils . . .

yep, perfect signiture i'd say. good one qc...

tailgunner, good idea. other options in props. 4 blade 20p... i agree, let the prop pros comment on that over in the prop forum i'd think.......

however a 19 is probably a underkill

agree'd, ya miss understood. i was refering to my boat on that 19p. i went from a 21p. guess i should have been more clear in my statement. on calvinman's i was thinkin 21p instead of 23p. now yer new idea of a 4 blade....always to many options it seems......

 

[tashasdaddy]

Re: Hydrofoil or trim tabs?

i wasn't suggesting he go to a 19. just one drop down.

 

[John_S]

Re: Hydrofoil or trim tabs?

I'd recommend installing Smart Tabs and retesting your accel and WOT before deciding on a new pitch or type of prop. Doing the prop then tabs, might have you looking at another prop change.

 

[Tail_Gunner]

Re: Hydrofoil or trim tabs?

I'd recommend installing Smart Tabs and retesting your accel and WOT before deciding on a new pitch or type of prop. Doing the prop then tabs, might have you looking at another prop change.

Agreed, but at 30mph or Wot tabs are going to do little to affect how well the boat or hull and prop are working together, or maybe i should say in my example the prop generated enough lift it took the tab's out of the equation......opps actually they @ that point kept the boat from wobbling or chine walking.

 

[calvinman]

Re: Hydrofoil or trim tabs?

Yes, I think smart tabs are a necessity for my boat, after all “friends Don’t let friends use hydrofoils 8)

When I go out to see if they will fit without interfering with the ladder and such I will check and see if the anti-cavitation plate is above the keel of the boat or not Tailgunner. What difference does this make?

I would certainly love to get my hands on a SS four blader, but that will have to wait, besides this way I will be in awe all next summer with the performance of the smart tabs and a 21 pitch prop and when I am used to the extra performace of these improvements I can slap on a nice SS prop and be in awe all over again!

Yes Ziggy the internet is wonderfull for finding out what works and what doesn’t. Much better than going out and making the same mistake.

I will have to get in touch with the folks at smart tab and see just how far the tabs extend(don’t want my kids banging their shins on them now do I.
:%

 

[danie]

Re: Hydrofoil or trim tabs?

Hydrofoils are dangerous when cornering at speed. Chucked mine and worked on the setup. Now what a pleasure.

 

[ziggy]

Re: Hydrofoil or trim tabs?

Yes Ziggy the internet is wonderfull for finding out what works and what doesn’t

this is true. but i was refering to the idea of going out to yer dealer and seein if he'll let ya try a prop w/o buying it. to see if it's what ya need.....