Go Back  Offshoreonly.com > Technical > Prop Talk
Help with prop to Chris Craft 260 Stinger >

Help with prop to Chris Craft 260 Stinger

Notices

Help with prop to Chris Craft 260 Stinger

Old 07-11-2020, 03:33 AM
  #71  
Registered
 
Join Date: Jan 2009
Location: Finland
Posts: 484
Received 120 Likes on 76 Posts
Default

Originally Posted by JohanSweden
Okey, thank you for your help!

The funny thing is that some people here in Sweden, when I show them pictures and they look at my prop shaft height they say it looks fine.
That it should be no problem with the drive that high.. Even if I tell them its a non step heavy V-hull.

They say that I should look at my propeller instead and fix it because that could be the problem.. but maybe they dont really know what they talking about..?

So its really confusing
Put the boat to water and test, you have the spacer installed and water pickup modified. Find stock condition bravo 1 prop to test, and then we have baseline.
JaniH is offline  
The following users liked this post:
Griff (07-11-2020)
Old 07-11-2020, 03:52 AM
  #72  
Registered
Thread Starter
 
Join Date: Sep 2019
Location: Sweden
Posts: 273
Received 15 Likes on 11 Posts
Default

Originally Posted by JaniH
Put the boat to water and test, you have the spacer installed and water pickup modified. Find stock condition bravo 1 prop to test, and then we have baseline.
Yes man
Must install my new EMI Thunder exhaust first.
Hope I can get it done soon
JohanSweden is offline  
Old 07-18-2020, 03:31 AM
  #73  
Registered
Thread Starter
 
Join Date: Sep 2019
Location: Sweden
Posts: 273
Received 15 Likes on 11 Posts
Default

Heres some new numbers:

@4950-5000 rpm - 49-50 mph
@4650 rpm - 53 mph

At 4950-5000 rpm the drive was out a bit, frowing a rooster tail.
At 4650 rpm it was less out.

the slip is at 35% now

Maybe its the right way with lower drive/prop shaft.

Broke the shift cable on the way back home.. couldnt get the neutral or reverse in.. Maybe the shift cable have jumped out of its position in the drive...?





Last edited by JohanSweden; 07-18-2020 at 04:31 AM.
JohanSweden is offline  
Old 07-19-2020, 05:21 AM
  #74  
Registered
 
Join Date: Jan 2009
Location: Finland
Posts: 484
Received 120 Likes on 76 Posts
Default

Going to the right direction, and this was with your 26" bravo? If so, try the stock 24" bravo next.
JaniH is offline  
Old 07-19-2020, 05:51 AM
  #75  
Registered
Thread Starter
 
Join Date: Sep 2019
Location: Sweden
Posts: 273
Received 15 Likes on 11 Posts
Default

Originally Posted by JaniH
Going to the right direction, and this was with your 26" bravo? If so, try the stock 24" bravo next.
Exactly, I forgot to mention that. This was with my Bravo 26”.

See if I can borrow the 24” or buy one
JohanSweden is offline  
Old 07-20-2020, 04:33 AM
  #76  
Registered
Thread Starter
 
Join Date: Sep 2019
Location: Sweden
Posts: 273
Received 15 Likes on 11 Posts
Default

Actual numbers with the 2” spacer, prop shaft height at 2,3” below bottom.

I have one guy that wants to trade his Bravo XR lower for my Sportmaster. The prop shaft height will be at 3,7” below bottom with the standard XR lower.


Mercury slip calculator:




JohanSweden is offline  
Old 07-20-2020, 12:26 PM
  #77  
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha/LOTO
Posts: 19,516
Received 1,783 Likes on 884 Posts
Default

When you trim up, the rpms goes up, but speed goes down and slip% goes up.
The drive still needs to go deeper.
Griff is offline  
Old 07-20-2020, 12:55 PM
  #78  
Registered
Thread Starter
 
Join Date: Sep 2019
Location: Sweden
Posts: 273
Received 15 Likes on 11 Posts
Default

Originally Posted by Griff
When you trim up, the rpms goes up, but speed goes down and slip% goes up.
The drive still needs to go deeper.
Exactly, thank you.

I tried to trim up a little bit at a time till I got the highest mph numbers —> 52,7 mph @4650 rpm I think the gauge did say.
When I trimmed upp more, the speed went down and rpm went up along with the rooster tail at the back...


Thinking of trading my Sportmaster lower in for a Bravo XR lower. Im getting like $830 in between from the guy that wants to trade it. Don’t know if its a fair deal..
It will take me to 3,7” below bottom.
JohanSweden is offline  
Old 07-21-2020, 01:09 AM
  #79  
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha/LOTO
Posts: 19,516
Received 1,783 Likes on 884 Posts
Default

Originally Posted by JohanSweden
Exactly, thank you.

I tried to trim up a little bit at a time till I got the highest mph numbers —> 52,7 mph @4650 rpm I think the gauge did say.
When I trimmed upp more, the speed went down and rpm went up along with the rooster tail at the back...


Thinking of trading my Sportmaster lower in for a Bravo XR lower. Im getting like $830 in between from the guy that wants to trade it. Don’t know if its a fair deal..
It will take me to 3,7” below bottom.
I would trade him as long as you can verify that it is as good of condition as yours. You will never see any added benefit from the SM lower at the speeds you will see.
Griff is offline  
The following 2 users liked this post by Griff:
JaniH (07-21-2020), JohanSweden (07-21-2020)
Old 07-21-2020, 03:54 AM
  #80  
Registered
 
Join Date: Jan 2009
Location: Finland
Posts: 484
Received 120 Likes on 76 Posts
Default

Originally Posted by JohanSweden
Exactly, thank you.

I tried to trim up a little bit at a time till I got the highest mph numbers —> 52,7 mph @4650 rpm I think the gauge did say.
When I trimmed upp more, the speed went down and rpm went up along with the rooster tail at the back...


Thinking of trading my Sportmaster lower in for a Bravo XR lower. Im getting like $830 in between from the guy that wants to trade it. Don’t know if its a fair deal..
It will take me to 3,7” below bottom.
go for it! I am afraid your slip numbers wont get much better if you dont go down 1-1.5 inch with you prop shaft. Even if it is 1.5 ratio i would buy it. There should be 10mph hidden somewhere, if the engine is working like it should.

Last edited by JaniH; 07-21-2020 at 04:00 AM.
JaniH is offline  
The following users liked this post:
JohanSweden (07-21-2020)

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.