It is currently Thu Mar 28, 2024 8:38 pm




Reply to topic  [ 9 posts ] 
 Kohler Command Crank 
Author Message
MMT Member

Joined: Thu Jan 17, 2019 10:15 am
Posts: 18
Post Kohler Command Crank
I was wondering if a 40 hp Kohler Command Crank, being a 63 mm stroke, would fit in a 25 hp block, normally being a 63 mm stroke. With or without, too much modifications. Is the valve height, from the deck, about the same on the heads? Will I have to cut the bottom of the cylinder wall out for the rotation of the crank weights? Trying to build a stroker engine. Looking for the low end, 3000-5000 RPMs, torque of an under square engine. Any help would be greatly appreciated!


Wed Jun 19, 2019 10:26 pm
Profile
MMT 1000 Club
User avatar

Joined: Tue Jan 13, 2009 6:42 pm
Posts: 2377
Location: West Coast Wisconsin
Post Re: Kohler Command Crank
Midwest supercub.


Thu Jun 20, 2019 6:29 am
Profile
MMT Member

Joined: Thu Jan 17, 2019 10:15 am
Posts: 18
Post Re: Kohler Command Crank
Upon farther research it woul actually be a cv750 crank witch is 69 mm stroke to replace the ch25 crank at 67 mm. Is it possible?


Thu Jun 20, 2019 3:31 pm
Profile
MMT Member

Joined: Thu Jan 17, 2019 10:15 am
Posts: 18
Post Re: Kohler Command Crank


Thu Jun 20, 2019 3:39 pm
Profile
MMT Super Elite Member

Joined: Fri Dec 18, 2009 8:10 pm
Posts: 16915
Location: Rowlett, TX
Post Re: Kohler Command Crank
The cv750 crank will fit. Same block. The 40 is a totally different engine. That little change in stroke isn't going to change much. The difference between the 25 kohler and the 30 on a boat is not much at all.

I think you'd be better off with big ass pistons and new sleeves.

I think you'd be even better off by just starting with the biggest block available rather than dumping a bunch of money in a block thats 20 lbs lighter. I been there, done that, got the t shirt. Big block is better.


Sent from my SM-T710 using Tapatalk


Thu Jun 20, 2019 5:17 pm
Profile
MMT Member

Joined: Thu Jan 17, 2019 10:15 am
Posts: 18
Post Re: Kohler Command Crank


Sat Jun 22, 2019 11:31 am
Profile
MMT 1000 Club

Joined: Mon Dec 31, 2012 11:07 pm
Posts: 4820
Location: West Monroe, LA
Post Re: Kohler Command Crank
Or get a boat that doesnt need as much engine to push it, and keep yours together longer by not stressing it as much.

#CFFITR
#GhostBoat
#Whoneedsphysicsihaveamudmotor


Sat Jun 22, 2019 11:44 am
Profile
MMT Member

Joined: Thu Jan 17, 2019 10:15 am
Posts: 18
Post Re: Kohler Command Crank


Sat Jun 22, 2019 12:18 pm
Profile
MMT 1000 Club

Joined: Mon Dec 31, 2012 11:07 pm
Posts: 4820
Location: West Monroe, LA
Post Re: Kohler Command Crank
I understand wanting to build. Trust me. Plenty here know the research I went through and was close to cutting into the cylinders of a small block Kawasaki. Just know for those kohlers, if midwest supercub cant help you with how much to cut and using a different crank (with info if they arent doing parts), then you're mostly out of luck on getting specifics on what you should do. Cb is about the only one here that put any real effort into the small block Kohler, and he isn't one to keep secrets about how well it went. If you've got the money to play, then so be it, but that engine without the extreme measures in building on an 1844 or 48 would run quite a bit better than it's current hull.

#CFFITR
#GhostBoat
#Whoneedsphysicsihaveamudmotor


Sat Jun 22, 2019 1:08 pm
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 9 posts ] 

Who is online

Users browsing this forum: No registered users and 251 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to: