Need some help!!!

[FRO_21]

I have a 21 ft cougar with twin 300 hp mercs on it and i am having problems with getting the boat to plane out. Some people are telling me I have the engines too low in the water and thats why it has a hard time planing out. Both engines are mounted center of the tunnels and what i really need to know is how high the engine should be mounted from the bottom of the hull or the top of the tunnel??:confused:

[LakeTrash]

2.5s or 3.0s ??

LT

[FRO_21]

i have a 21 ft cougar with twin 300 hp mercs on it and i am having problems with getting the boat to plane out. Some people are telling me i have the engines too low in the water and thats why it has a hard time planing out. Both engines are mounted center of the tunnels and what i really need to know is how high the engine should be mounted from the bottom of the hull or the top of the tunnel??:confused:
2.5's

[2.5_stoker]

seems like that thing should be a rocket out of the hole...how high are the motors mounted now (center line of the prop shafts in relation to the bottom of the boat) and what are you spinning for props?

[FRO_21]

:confused:i have to go to the boat and measure it but if i remember right it is about 6 inches below the hull and i'm spinning 28 cleavers.

[perfmarine1]

Prop shafts should be even with bottom of boat, not top of tunnel. You will need low water pick up lower units, I would hope you know that. If motors are mounted in the tunnels that is the problem. Too much drag on take off and boat has to sit very low in the water that will add to hard to get on plane.. Not sure why you need 2-300's on a 21' cougar. Boat should do well over 100mph with 1-300. Skid plates will probably help if you don't have them, water is probably hitting the set back plates also. Or better yet, jump up to a 23' with those motors, much better suited for twins.

[FRO_21]

Yea both motors have low water pick ups and they are mounted in the center of the tunnels. The prop shafts are level with the bottom of the hull but they are 6 inches from the top of the tunnel. Is there anything i can do with power jack plates or am i wasting my money on them.

[2.5_stoker]

you should be able to get that set up dialed in...talk to wildman here on the board he has experience setting up 21's with twin 2.5's...he sets up liberators but they are very similar to your boat and I'm sure he can get you headed in the right direction...