Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

Sign in to follow this  
bewls

Best Prop for Response with 409SS Monsoon

Recommended Posts

bewls

Hi, I have recently bought myself a 2014 Response with 409SS engine upgrade. We mainly use it for skiing and barefooting but seems to be revving high with the standard Acme 515 prop on it. Has anyone got a 449 or 425 prop on their boat? Which one would you recommend to go with the 409SS engine?

Cheers

Share this post


Link to post
Woodski

@bewls:  what is the RPM:MPH ratio at skiing and barefoot speeds?  With a 1:1 gearbox, you should see pretty close to 1000 rpm per 10 mph.  The techs at Acme will provide some pretty good information on prop details and each step effect of bumping up the pitch.  I recall w/o my notes the 515 > 449 change was ~200 rpm drop, but I would call Acme to confirm.  Also, I would compare your speed control RPM to the tach reading to verify the accuracy of the tach (or both!). 

 

Share this post


Link to post
bewls
20 hours ago, Woodski said:

@bewls:  what is the RPM:MPH ratio at skiing and barefoot speeds?  With a 1:1 gearbox, you should see pretty close to 1000 rpm per 10 mph.  The techs at Acme will provide some pretty good information on prop details and each step effect of bumping up the pitch.  I recall w/o my notes the 515 > 449 change was ~200 rpm drop, but I would call Acme to confirm.  Also, I would compare your speed control RPM to the tach reading to verify the accuracy of the tach (or both!). 

 

Thanks @Woodski you are correct in that 1000rpm per 10mph but it seems die off over 4000prm. I'm just not sure if it's ideal for a motor to be doing 4600rpm towing a barefooter and if this uses a heap of gas in doing so.  I will call the people at ACME to see what they say.

Share this post


Link to post
ahopkinsVTX

@Dare2goBare may be able to provide some good insight for you.

Share this post


Link to post
Dare2goBare
19 hours ago, bewls said:

Thanks @Woodski you are correct in that 1000rpm per 10mph but it seems die off over 4000prm.

Yup.... after 1k it does die off from 1k to 10 mph,  I'm running the 515 and top out 47 mph @  5100 rpm. Thats with a full tank

and a crew of five with gear, at sea level and the same at the lake, 1300 ft.. Now the 409 purrs like kittin when we're footing,  Im at 42 Mph with my footing and have no concerns what so ever. A solid constantly pull up to speed! :rockon: but yes she does drink a bit more!

On a side note I forgot to mention, ACME will recommend the 515 for your boat with the 409.

Edited by Dare2goBare

Share this post


Link to post
ahopkinsVTX

To the OP, my concern with changing out the prop to achieve lower RPMS at 40+mph is she is going to be a dog out of the hole for anyone that slaloms. Now, if you and your buddies don't slalom at all that probably isnt a factor. Although I would keep the 515 for when you go to sell it as most interested in the boat will be skiers.

Share this post


Link to post
Steve B.

I've wondered if folks have experimented with two blade props on our rigs?

Steve B.

Share this post


Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...