Just added a Hustler. Max mph question

[sweetchuck08]

I have a 2007 Tahoe Q6 SF with a 4.3L 190hp merc. Alpha 1. 1.81 gear ratio. My boat with the stock prop,a 14.25 x21 hit 4800rpm wot and 44mph. I just installed a TurningPoint Hustler 14.25 x21 prop. With it my maxspeed was 44mph at 4600 rpm wot. I was really hoping to see more top end. Any suggestions? I also should add i have SmartTabs SX. Had them for both prop readings. Thanks

 

[90stingray]

Re: Just added a Hustler. Max mph question

My glastron with the same setup as yours will turn a 23p 3 blade alum to 4800 and over 50mph. I run a 3 blade ss 21p that will get me 48mph at 4650. That turning point... is that their 4 blade variety? If so, the loss in top mph is not a surprise. You should have stepped down in pitch if going to 4 blades. Your original setup is getting 17% slip. Where the hustler is getting a more reasonable 10%. If you are wanting the top mph... stick with 3 blades. Maybe try something in a ss variety. How was the holeshot with the hustler prop? With 4 blades AND trim tabs that should pop right out of the water.

 

[sweetchuck08]

Re: Just added a Hustler. Max mph question

Mine is the 3 blade prop. Reason i dont go stainless is the upper niagara river can get pretty shallow in some spots. I like to fish and sometimes i get myself where i probably shouldn't. Much cheaper to replace props than outdrives. You think a 23p aluminum would only raise me 200 rpm?

 

[90stingray]

Re: Just added a Hustler. Max mph question

The 23p will lower your top rpm. You should still be in the acceptable range. If the motor can swing it, you will pick up some mph and lower your rpm. But with that hustler you are already down in rpm... i dont know if i would want to go any lower. But if all you want is the speed, then give it a go. I usually want to prop my boats for upper end of rpm range.

Are your tabs working properly? Could they be holding you back... keeping bow down too much? I would think with that original 21p you should be able to hit rev limiter. Something seems off...

 

[jkust]

Re: Just added a Hustler. Max mph question

Well lets figure this out. I currently own three Hustler props identical to yours as each is a 21" and use two of them on my SIG boat. (one for unfamiliar or shallow lakes with a few dings and one that hasn't ever seen the bottom yet). Our boats seem relatively similar but I have an extra 200lbs of dry weight over your Tahoe and also 33gallon tank of fuel. My top speed with that identical carbed 4.3 and Hustler is over 4mph higher on GPS at 4850rpms which is all she'll do. To me the top speed of the little boats we have that are so similar have one big difference and that is the build weight all else the same. In other words you will see some 18 footers that are only a hair over 2000lbs and some that are up to 3000lbs and the weight is where you get those extra mphs. Of course the feather weigh Glastrons and others are going to kill your top end as they aren't built to the same standard or maybe have lighter accessories or just less stuff. My issues with your numbers is that my boat is ultra heavy for an 18 footer and there is just no way it should top out at higher rpms and that much more speed over yours. The original 21" Black Max prop with no cupping or anything fancy would blast through 4850 rmps and easily go over 5000 if you weren't careful. The BM above would top out at 51.8mph on GPS.
What load of passengers are you taking when you get these numbers?

 

[BoatDrinksQ5]

Re: Just added a Hustler. Max mph question

I have a 2007 Tahoe Q6 SF with a 4.3L 190hp merc. Alpha 1. 1.81 gear ratio. My boat with the stock prop,a 14.25 x21 hit 4800rpm wot and 44mph. I just installed a TurningPoint Hustler 14.25 x21 prop. With it my maxspeed was 44mph at 4600 rpm wot. I was really hoping to see more top end. Any suggestions? I also should add i have SmartTabs SX. Had them for both prop readings. Thanks

What pound actuators on the tabs? what hole position? could be 'over tabbed'?

FWIW.....My 19.5' Q5SF with same carb'd engine and a generic BlackMax 23p gets me around 4700 rpm and 47.5mph with 4 adults and trollingmotor/battery. only had a few short runs with it (run outa lake!)...so i bet playing more with trim and less wind i could easily get to 48 or 48.5mph with 4adults

 

[jkust]

Re: Just added a Hustler. Max mph question

What pound actuators on the tabs? what hole position? could be 'over tabbed'?

FWIW.....My 19.5' Q5SF with same carb'd engine and a generic BlackMax 23p gets me around 4700 rpm and 47.5mph with 4 adults and trollingmotor/battery. only had a few short runs with it (run outa lake!)...so i bet playing more with trim and less wind i could easily get to 48 or 48.5mph with 4adults

I'll tell you the big difference between the Black Max and the Hustler besides the rpm robbing cupping is that I can trim the Hustler as far as I want and it absolutely will not blow out so to get even 48.5mph with the hustler I'm trimmed up crazy far. The BM on the other hand was the king of the blow out on turns and couldn't trim up nearly as far but you didn't have to to get more speed. The hustler will shoot a full rooster at 48.5mphs I didn't think was evev possible with an I/O while the BM couldn't be trimmed anywhere near that far so as to shoot any water. Also the Hustler makes the Chap porpoise like nobody's business which is annoying and I don't want to add tabs when I know it is the prop causing much of it. The BM didn't have near the porpoise.

 

[90stingray]

Re: Just added a Hustler. Max mph question

Hey, lets try to keep it about the op issue and not how glastron is inferior to chaparral. I wasnt bragging about my speeds... just simply stating my specs for comparison. And how something is not adding up. My money is on the trim tabs...

 

[steelespike]

Re: Just added a Hustler. Max mph question

Yeh, lets try it with the tabs fully released.You seldom find boats with similar setups to compare
If it still struggles to make rpm and speed some things to consider are.
Is the bottom clean and smooth?
Does the throttle open all the way?
Is the Tahoe a deep V?
I too feel it should be in the 50 mph area and maybe even over revving with a 21.

 

[sweetchuck08]

Re: Just added a Hustler. Max mph question

Thanks for the posts everybody. My boat weighs 2800lb dry weight. I have a filled 45 gallon gas tank. It was only me in the boat when i did the test. The engine according to the mercruiser website has a max rpm range of 4400-4800. I was hitting 4800 with my 21p black max and trim tabs,. The trim tabs may be an issue, but i don't want to mess with that till i get the prop taken care of. I don't feel any digging and it planes very quickly. I thought u lose rpms by going down in pitch, not up? I have played with my outdrive trim, and yes i can trim much higher without any blowout.

 

[90stingray]

Re: Just added a Hustler. Max mph question

A 17p will rev thru the roof. Where a 23p will bog you down more. The inches of pitch are theoritical inches of fwd movement. You have to have some slip... so you dont end up moving as far as anticipated.

You may be hitting 4800... but you should be able to over-rev that 21. If you follow the advice of disabling the tabs... you will find a better solution with the prop. You dont want to buy a prop if you have other issues...

 

[steelespike]

Re: Just added a Hustler. Max mph question

Exactly, you need to release the tabs to get back to boat only ride and speed.
as long as the tabs are involved you can't be sure of the boats maximum performance.
You only need to release the tabs and be sure they aren't dragging
All ways one change at a time and test.

 

[sweetchuck08]

Re: Just added a Hustler. Max mph question

Well as far as the over reving, thats never happened. Way back before I got the tabs, even when the boat was brand new with that stock 21p blackmax, my max rpm's were still only 4800. I also had my timing checked and I know it is where its supposed to be. I'll try adjusting the tabs as soon as I get the chance to get the boat back on the trailer. I have them in the middle hole now, I plan on moving them to the first hole (closest to the boat). That should make there effect as minimal as possible.

 

[Maclin]

Re: Just added a Hustler. Max mph question

You could try the "lightest" hole setting now like you are thinking to do, and compare, simple enough procedure. Just do one thing at a time, with the same prop, etc. I think you have the right methods in mind.

Ideally though some tuning to the tabs was done after installation. Did you note the top speed before and after tab installation? The tabs should have allowed the same top MPH as before, or maybe a slight gain according to Nauticus. When dialing in the tabs if the top speed went down then go to the next lighter mount setting and try again. Change the settings until MPH is the same as pre-tabs or as close as possible, all of this with the same load and prop. Each boat responds differently. If this tab dialin-in tuning was not done then "release" them until you are through with the prop tuning, then dial the tabs in again. Nauticus has a slick lever type mount available for this, so you do not have to tie them up or take them off.

If after all this, when dialing in the tabs, if the lowest setting causes measurably lower top MPH than pre-tab condition with same-same prop and load then sometimes the next lighter pistons may be more correct for the boat. Nauticus has all this info on their site, and also are just a phone call away for good advice.

 

[jkust]

Re: Just added a Hustler. Max mph question

Hey, lets try to keep it about the op issue and not how glastron is inferior to chaparral. I wasnt bragging about my speeds... just simply stating my specs for comparison. And how something is not adding up. My money is on the trim tabs...

I don't care about inferiority, I do care about the extra weight the OP has over lighter boats. He wasn't considering his heavish weight and large gas tank and you mentioning that your GT goes x mph could be confusing as it is at least 400lbs lighter plus the extra gas in his huge gas tank. That's like two 200 lb guys extra in his boat over yours plus a kid that weighs as much as the difference between his tank and yours and thats if you have the heavy GT not the 2100lb 4.3 version. There is more going on than meets the eye given he and I are similar weight but I'm getting a bunch more performance out of a boat not meant for performance and we amazingly are running identical props.