Top speed seems low.

[bigred1mp]

1994 Wellcraft Nova 202 Spyder with 4.3l Volvo Penta and 15x17 steel prop.
Boat is kept in a trailer in a garage never stored in water.
Rochester quadrajet
No damage to prop, hull or out drive.
Hull is clean and smooth
No tabs
Boat weighs approx 2900 pounds.
40 gallon fuel tank

So that's my boat and my issue is running at 4200rpm my top speed with 3/4 fuel no gear whatsoever and two adults is 34mph GPS and speedometer. Speed read on lake with little to no breeze and no waves or chop.

I know I have a heavy boat with a 4.3l but I feel like I should hit at least 40 to 43mph top speed with my setup.
Am I wrong or is something wrong

 

[Scott Danforth]

if 4200 RPM is all you are getting out of it, you are either running on 5 cylinders with one dead one, your flappers have dropped and are choking off the motor, you have a tired motor or something.

WOT should be closer to 5000

is this a new to you boat, or is this a new problem, or a persistent problem?

is that actual weight, or is that the published weight from 27 years ago?
are you trimmed out properly?

have you done a compression test?
have you checked the fuel system?
have you read the spark plugs?

 

[alldodge]

Agree, check the motor out and see if its up to spec
Your on the low end of the rpm, finding 4200 to 4600 for WOT

http://boatinfo.no/lib/volvo/manuals/43abcde.html#/32

 

[QBhoy]

Hi
before you go in too deep...I’d ask if you are trimming up properly ? This can see hundreds of rpm difference
and in an average case a 5-10mph difference.
I’d also say that your boat is just over 20ft, heavy for a 4.3 and also...if your fuel tank is 3/4 full...that’s about the equivalent of 2 more people onboard.

Just a thought.