99 american offshore 3100
#1
Thread Starter
Registered
Joined: Jul 2010
Posts: 105
Likes: 0
hey guys I got my new boat a couple weeks ago, absolutely love the boat, was hoping for a little more speed, but its rock solid. its running 500efi motors, 12'' stelling boxes, 1,36 drives, 30p box stock bravo props turning outwards, boat runs 90-92 at 5000rpm any tips or tricks to squeeze a little more top end out of this thing. comes on plane in 30ft great and cruises wicked!
#3
Platinum Member

Joined: Jan 2002
Posts: 122
Likes: 5
From: gainesville, ga
You could lab finish your props.. but I would buy another sets of 30 and have them lab,,You could blue print the hull.. But that is going to be pricey.. You could change gear ratios to 1.50 and maybe go with a larger prop...But if your are smart ..just enjoy it and learn your boat.. do not over trim the boat..
Bc
Bc
#4
Thread Starter
Registered
Joined: Jul 2010
Posts: 105
Likes: 0
That's what I was thinking, I have a set of 27.5p hydromotive p5x props that came with the boat, I might try them and see how they act. I would like to be able to spin to the rev limiters loaded light. I don't plan on doing much, the boat outruns most of the boats on our lake already so it's pointless trying to go faster, other then a couple big dollar nortechs with qv4 motors.
#5
Registered

Joined: Aug 2004
Posts: 1,335
Likes: 1
From: Riverview, Michigan
I agree with BC. Most 31 Chris Cat hulls with 500HP power use (and perform the best) the 1.50 ratio. Best info provided by BC, Do Not over trim the boat. If you are truly after more top end speed, stick with a 4 blade prop.
#7
Registered

Joined: Mar 2002
Posts: 114
Likes: 5
From: Traverse City Michigan
If you don't have nose cones on your drives you need them. Anything over 80-85 MPH on these boats adding a nosecone adds 10MPH. I have had several of the 3100's and fooled with them quite extensively. If the motors are stock you probably need stock 28 B1's on there. I have always had better results with stock B1's over labbed ones.
#8
Gold Member
Joined: Oct 2002
Posts: 182
Likes: 0
with the extension boxes the centerline of the propshaft should be 0 inches to 1.5 inches above the bottom( I run 1.75 inches on my boat) of the sponsons.to get the props close to surfacing.if they are below the bottom of the sponsons you are getting too much drag. you should drfinitely have nose cones. stick with the 4 blade bravo i props. should definitely run close to 100 mph.
#9
Thread Starter
Registered
Joined: Jul 2010
Posts: 105
Likes: 0
[QUOTE=quest;4265269]with the extension boxes the centerline of the propshaft should be 0 inches to 1.5 inches above the bottom( I run 1.75 inches on my boat) of the sponsons.to get the props close to surfacing.if they are below the bottom of the sponsons you are getting too much drag. you should drfinitely have nose cones. stick with the 4 blade bravo i props. should definitely run close to 100 mph.
what brand nose cones should I go with?
what brand nose cones should I go with?



