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sanjuan23
05-24-2006, 04:15 PM
Okay so we are out last weekend running down the river. I have the Throttle full open and only turning about 3600 RPM. The owners manual says max is 4600. I realize there are variables in concerns to speed (weight, wind, water, etc.) But what is the target RPM I should be hitting with the throttle fully open? 1992 Prostar 205 w/351 HO 1:1. Any help will be greatly appreciated.

TMCNo1
05-24-2006, 05:13 PM
With the original OEM prop, probably a 13x13, the normal max rpm should be about 4200 to 4400 and with corrected speedometers 42 to 44 mph depending on gas octane, tune-up, wind, water temp, fuel, people and gear onboard.

G-man
05-24-2006, 05:26 PM
Let us know what prop is on your boat. As tmc#1 said between 4200-4400 is normal. max is 4600, only use a gps for speed indication because the speedos can be way off. Tach can be off but not usally.

92 190 PS
05-24-2006, 05:29 PM
I have a 92 Prostar 190 with a 351, 1:1 and a 13x13 prop and I'm running right at 43 mph at 4300 RPM's. Good luck.....

sanjuan23
05-24-2006, 05:35 PM
Not really concerned about the speed. Reason being that I am just concerned if things are running correctly. The speedos were reading about 43 which I am throughly convinced are not reading correctly. I dont know if the prop is original or not. Although I did do a nice job of putting a few nicks and small bends in the edge against the boat ramp. No vibration though. Long story! So I assume this may have a direct correlation to the RPM not reaching 4k. Could I be wrong?

TMCNo1
05-24-2006, 05:36 PM
I have a 92 Prostar 190 with a 351, 1:1 and a 13x13 prop and I'm running right at 43 mph at 4300 RPM's. Good luck.....



Like I said........................
On our '89 351/240 hp 1:1, I'm running a 4 blade OJ S/S, 13x13, and it's turning 4350 @ 43 mph w/ corrected speedos.

TMCNo1
05-24-2006, 05:44 PM
Not really concerned about the speed. Reason being that I am just concerned if things are running correctly. The speedos were reading about 43 which I am throughly convinced are not reading correctly. I dont know if the prop is original or not. Although I did do a nice job of putting a few nicks and small bends in the edge against the boat ramp. No vibration though. Long story! So I assume this may have a direct correlation to the RPM not reaching 4k. Could I be wrong?


Your speedos are probably way off and you will be suprised just how little damage done to a prop can kill it's effectivness in the water. You don't have to have a vibration to loose performance. I would first have the prop repaired or get a new one and see if your performance will improve. Let us know what happens!

pkskier
05-24-2006, 05:49 PM
B & B Propeller in Richland Hills or James Propeller in Dallas can repair your prop and both do a good job.

east tx skier
05-24-2006, 07:30 PM
Mine turns 4,600 max at 45.5 mph.

skitilldark
05-24-2006, 09:15 PM
This wasn't by chance your first time out was it? Could be the unstable fuel from winter storage maybe. I know that's a long shot, but low octane can do a ton on top end.

sanjuan23
05-24-2006, 10:16 PM
Wasnt the first time out this year. Didnt know how long the fuel was in the tank from the day I bought it. It was more than when I test drove the boat. I did fill'er up the 2nd weekend we had her with premium. So I havent fully gotten rid of the previous owners gas. I know that the prop situation has probably slowed it down some but 800 rpm? I am concerned about shaft alignment or should I, restricting the additional rpm's. I am not the go fast type just want to know that when I need it, its there. Changed the oil, tranny fluid, spark plugs and cleaned the flame arrestor. But have not put the boat in the water since.

Hoosier Bob
05-24-2006, 10:25 PM
GPS it, I have a hard time believing you are getting 40+ out of 3,600 rpm with a standard 13x13. Check 20, 25 and 30 to see if you are still close to the 1 to 1 range. If you are you may have a misreading tach. A few on here have purchased new props for a 1.5/powerslot and realized later they had a 1/1. That would make your max rpm around 3100. :confused: Wasnt the first time out this year. Didnt know how long the fuel was in the tank from the day I bought it. It was more than when I test drove the boat. I did fill'er up the 2nd weekend we had her with premium. So I havent fully gotten rid of the previous owners gas. I know that the prop situation has probably slowed it down some but 800 rpm? I am concerned about shaft alignment or should I, restricting the additional rpm's. I am not the go fast type just want to know that when I need it, its there. Changed the oil, tranny fluid, spark plugs and cleaned the flame arrestor. But have not put the boat in the water since.

skitilldark
05-24-2006, 10:26 PM
Hey..at least you're doing better that I am. I can't even get my boat to run yet!

sanjuan23
05-24-2006, 11:06 PM
True I do not really trust the speedos until I can get them dialed in. My brother in law was telling me run that sucker up to 4000 rpm and set them at 40 mph. I have a really hard time believing that is going to work. I have checked again and again I do not have the powerslot, based on the Hull ID# and looking at the "Velvet Drive" on the Transmission its self. So until I get the ideal conditions, make sure everything is running correctly etc. etc. I am not sure what to think. Just making sure it starts at the boat ramp everytime from now on!! :eek:

Hoosier Bob
05-24-2006, 11:12 PM
40 @4k should be correct assuming no headwind and limited cargo/passengers. Check your speed at 20/25/30 and check your tach in nuetral to see if it is reading. Check the stamp on the prop to verify 13x13. GPS to see if you are getting 40+ at 3600. After this you should find something. ;)

sanjuan23
05-25-2006, 02:15 PM
Just ordered the ACME 209 4 Blade from skidim excellent guys. Thanks for all the direction. Overnighted that sucker so I can put it on in the morning before heading out for the Memorial Day weekend. Any help on removal and installation would be great!

Kevin 89MC
05-25-2006, 04:26 PM
Get a prop puller. It's basically a C clamp with a split on the end to go around the shaft. I've never had good luck with anything else. Good luck.