97 stingray 180rs stock prop size?

hi i just purchased a 1997 stingray 180rs its powered by a mercruiser 3.0 can anyone tell me the stock size prop that came with this boat ? when i got it it didnt have one on it ,i dont want to just go start guessing and blowing money, my buddy had a 21p prop and i tried it but the tach is reading like 5900 rpm wot , sounds way too high !!!!!!!!!!gps speed was about 42 mph but if i trim it up at all it starts porpoising and bouncing all over ,if any body out there can help me figure this id apprecite it .thanx

Re: 97 stingray 180rs stock prop size?

Calculations derived from your test run make no sense:

21 pitch prop, assuming 2.0 gear ratio outdrive, 5900 rpm, and 42 mph...

That's not really possible.

One of these numbers is completely wrong. I will assume either the prop you tested was not actually a 21, or your tach is off by a substantial margin.

Test your tach. I expect it is wrong. Is it possible that completely missing exhaust bellows could be causing an insane amount of ventillation and slip with your prop? I dont' even know if that could occur...but it would explain your figures.

Can't recommend any prop with the data provided above. Basically if your numbers are correct, you need something like a 27 pitch prop to bring your rpms in range.....and there's no way a 3.0 motor could ever push 27 inches of pitch.

Most 3.0's runabouts of your size run 17 or 19 pitch props. A select few will will able to push a 21 at most.

And welcome to the Stingray porpoise club. You must either leave your trim down all the way for most speeds, or buy Smart Tabs, or buy a different brand of boat. Stingrays without tabs will always porpoise if you trim them out too early...and the small lightweight 18 footers are the worst of them all...

Re: 97 stingray 180rs stock prop size?

thanks for the response, im thinking your right about the tach being wrong im going to hook up a tach dwell meter tonight and go for a rip!! the ratio of the drive is 1.94 i believe the boat weighs aprox. 2100lbs . i use it for tubing, water sking,ect. the prop def says 21p on it im not sure the actual size 14-14 1/4? cant read that part. i had read somewhere that a 99 180rs came stock with a 23p but proformed better with a 21p and wot rpm should b around 4800 !!!!!! im going to order some smart tabs tonight and get back with actual rpm with the prop thats on it now!!!!!!

Re: 97 stingray 180rs stock prop size?

Ok back from the lake!!! Tach is all wrong!! Connected A digital tach to the engine and it said around 4650rpm at wot fully trimmed, gps bounced between 44-45mph !! That was with just me and a 1/4 tank of fuel , the specs on the engine stated wot 4400-4800 so I think the 21p is damn close to where I want to be !!! Again I do use this boat for tubing, and usually have about four people with me so before I order a nice ss prop at 3-400$ should I get a 20p for the extra weight of people or stick to the 21 ? The prop I have on it now it just a regular aluminum stock type , will a nice stainless 21p give me the extra proformance for the extra weight ? Thanks guys!!

Re: 97 stingray 180rs stock prop size?

so I think the 21p is damn close to where I want to be !!!

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Ayuh,... Agreed...

Again I do use this boat for tubing, and usually have about four people with me so before I order a nice ss prop at 3-400$ should I get a 20p for the extra weight of people or stick to the 21 ? The prop I have on it now it just a regular aluminum stock type , will a nice stainless 21p give me the extra proformance for the extra weight ?

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It's a 3.0l,... Ya don't need a SSteel prop, 'n No, it ain't worth all that gas Money...

If yer waterplayin' with a full boat, try a 4 blade 20"...
Otherwise, the standard 3 blade aluminum is All ya need...

Re: 97 stingray 180rs stock prop size?

Ahhhh...now your numbers line up like rockettes. Nice low single-digit slip number, typical for Stingray hull on most any prop.

IMO, I'd pitch it down a bit. If you're at 4650 with empty load, and you usually run substsantially heavier load, and you like to do watersports....that combo will put you at the bottom of your range, right when you want to be at the top of your range...

I wouldn't be surprised if a 4 blade in a 19 would make you happier, ESPECIALLY if you decide to go to stainless with aggressive cupping/rake at the same time, because the prop will bite better than your test mule, therefore bringing your rpms down more than you think (my Stingray actually calculates negative slip figures with a performance 4 blade stainless prop...yours probably will too) Keep it mind it might indeed over-rev just hair, maybe toward 4900-ish, when you're empty and running full out, and it might cost you a couple mph up top. BUT the holeshot and midrange improvement, and ability to handle a full boat of people, will be surprising for a 3.0...

But if you're satisfied with the overall performance of the current test 21, then just buy yourself another kinda like it. A known prop that you're happy with is better than a random mail-order guess that might be a bit off...

I'm a big fan of stainless myself. Not because you'll notice substantail performance improvements, but because they can last so much longer, can survive occasional gravel & silt digs unharmed, and can be rebuild repeatedly and indefinitely. I consider a nice stainless prop more of a long-term money saving investment than a performance adder for a 3.0....

Parking situation is a consideration as well. Locked in garage at home most of the time? Stainless. Left out on a public slip or outside in your neighborhood driveway? Suddenly pretty stainless becomes a thief-magnet....

Modern aluminum props will perform pretty much equal however, and cost less up front. They are less durable as well and you'll see what I mean when you accidently dig a gravel bottom for 2 seconds... Your call.

Re: 97 stingray 180rs stock prop size?

Im actualy pretty happy with the 21p , we went out the other day with 4 people total and it pulled 2 people on a tube pretty decent , I do like to go as fast as possible when it's just me and maybe 1 other person! What do u think about that high five prop ? I read that with that vent system with the holes in front of the pedals with there 23p it will take off like a 21p then when full speed water creates pressure sealing the holes and actualy gain a little top speed as well !!! The guy at the local marina has 1 he will sell me for 200.00! And it sure looks vicious !!!!!!!

Re: 97 stingray 180rs stock prop size?

Why not ask the local marina for a test drive on that prop before buying. Price is certainly good.

I think in a 23 it'll be way too much pitch and your RPMS will be way down. And never in my life have I heard of a High 5 INCREASING top speed...quite the opposite. It's a pulling prop, certainly not a speed prop...

You can put vents on any prop you like. Many others beside the High 5 come with vents right out of the box. And to add your own it just takes a drill bit and the guts to put a few holes in the right place...a fairly common home-brewed prop modification.

Tubing is no test for a prop...2 people on a tube can be pulled by a 40 hp fishing boat...

Do any of you ever slalom ski? If yes put a 200 pound person on the end of a rope for a deep water slalom start with 3 to 5 people on board...THAT's a true test of a boat's holeshot....still wondering if your current setup will be capable of something like that and if you'll wish you pitched down a bit more. But if you don't use it in that manner and are only tubing, wakeboarding, and two-skiing, or your slalomers are 160 pounds or less, then I agree what you have set up now will be absolutely fine.