1989 Chaparral 2100sx prop

[rad1026]

1) Performance issue you are trying to correct.
most of the time the boat is used for wakebording, skiing or pulling tubes.

2) Current prop manufacturer, model, aluminum or stainless as a minimum.
I run two props, both four blade aluminum 18 pitch and 16 pitch. Trying to get on plane quickly and stay on plane at slow speeds for wakeboarding

3) Current prop diameter and pitch (required).
I believe both are 14.5 diameter, pitches noted above.

4) Wide open throttle RPM and speed with an average load (very helpful)
4200 RPM at about 40mph with 18 pitch, the lake I spend most time on is about 3500' in elevation.

5) Engine/drive make, model, year, and HP
merc 5.7L 260 HP, alpha one gen one,

6) Boat make model, year, length and weight
1989 Chaparral 2100SX, 21', brochure says 2800 lbs.

I want to go to a stainless prop to see if I can get a better hole shot and more traction on sharp turns. Merc makes great props but they are very expensive. I tried a 3 blade 19 pitch prop on this boat when I first bought it. It was a quicksilver prop but didn't seem to get on plane quickly and cavitated badly on sharp turns. The three blade would not keep the boat on plane at slower speeds. The four blade seems to do a great job of that.

 

[Bondo]

Re: 1989 Chaparral 2100sx prop

Trying to get on plane quickly and stay on plane at slow speeds for wakeboarding

Ayuh,..... Have ya considered Trim Tabs,..??

I'll let the more experienced comment of Who's blades are Best....
I've never really propped a hull for yer purposes....

I'd expect yer gonna have to pay the premium price for custom SSteel...
Used is an option, once ya figure out what to Look for,...

 

[Philster]

Re: 1989 Chaparral 2100sx prop

Well, step down in pitch and focus on stern lifter props if the smallest prop is the one returning 4200 RPM at WOT. You would be looking at 4-blade props of 15p. The prop should be vented, 4 blades, 15p, SS and advertised as a stern lifter.

Yeah... Merc props are expensive, but boy do people love the Bravo props from Merc.

 

[rad1026]

Re: 1989 Chaparral 2100sx prop

What about something like this?

http://www.turbo-props.com/products/turbo-22-th-series_th22

 

[rad1026]

Re: 1989 Chaparral 2100sx prop

Also, Michigan Apollo, Powertech ELE series and Turning point all make a stainless steel 4 blade. Apollo is 14-1/8 x 18, Powertech is 14-1/2 x 19 and Turning Point is 14 x 19. What differences will I notice between the diameter and pitch if they are this close and which manufacturer would you go with?

 

[Philster]

Re: 1989 Chaparral 2100sx prop

Whoa...19p??? You need to go down from 18p and not up. You're 18p is the baseline, since you gave specs for that.

Since you can only spin a 14.5", 18p, 4B prop to 4200. You should be thinking about an SS prop of 14.5", 4B and 17p.

You need more RPM and not less RPM.

 

[rad1026]

Re: 1989 Chaparral 2100sx prop

I apologize, let me back up. My 5.7L carb engine specs max RPM from 4400-4800. I know my tachometer is unreliable so I usually consider the 4200 range as far as I run the engine for any extended period of time. I can go faster, I just usually choose not to. I think the 18 pitch is where I need to be. I can keep the boat around 17 to 20 mph and provide a good wake for the wakeboarders. I keep the 16 pitch for when I go to a couple higher elevation lakes here in the state. I guess what I'm looking for is the difference between the props I listed. What am I going to notice between the different diameters and pitch since some are so close. I really think the 14-1/8 x 18 is going to give me the best over all performance for what I do considering that is what I am using now in aluminum. Will the SS vented prop make a big difference in hole shot and turning? Is the Michigan prop a stern lifting prop? Are Michigan props good quality?

 

[Philster]

Re: 1989 Chaparral 2100sx prop

Michigan props are good props with good knowledgeable support.

An SS vented prop a wee bit smaller in diameter should be good based on a bit o' speculation, but you gotta do a WOT run and find out the true max RPM she'll turn now and not guess. <-- official disclaimer. And don't hold out info next time!

 

[Tail_Gunner]

Re: 1989 Chaparral 2100sx prop

2) Current prop manufacturer, model, aluminum or stainless as a minimum.
I run two props, both four blade aluminum 18 pitch and 16 pitch. Trying to get on plane quickly and stay on plane at slow speeds for wakeboarding

There is no known cure for a std I/O to hold a low speed plane it was designed to just the opposite. What is going on is you are creating a pressure wave...the boat is slowly gaining momentum climbing ontop of the wave or lets say hill at some point its there and off you go.

Wake board boats are designed to drag... Think about it they have built in water tanks to increase that effect.

Dont do this...with that said if you have a ski locker you could seal it well...gel coat it....drop in a bilge pump....create a intake valve..flood it and use the bilge to evacuate it during normal operation...But you may be creating a submarine at the same time.