Hi everyone. I bought a 1988 Nova XL 3 years ago. It's a good looking boat and great fun for our family. My "guy" issue with this boat is its top speed of 38 knots @4200rpm. I was thinking it should be more like 45 knots. It has a 454 330hp, quadrajet carb with Bravo 1 and a 23 pitch mirage prop. There is a 1/2" side to side looseness in the Bravo which I think by its age could use an overhaul and new pin to fix the loose. The carb is probably original and maybe affecting top performance. What top speed should I really be getting here, and what can I do to improve this? The basics are done, plugs , oils, filters, wires, coil, distributor, rotor..thanks

so, it is a 23 foot boat??
does sound a little slow,,
i guess start with prop, what are other people running with this boat.

23 feet correct. The previous owner put Fratello instead of Nova XL as the brand for some disappointing reason. I have read around online it should be a 50mph boat. Unless the owners bump up the truth a bit....

weight 4K - WOT 4200-4600

I'm thinking 3 possible issues

Prop, weight and age

Should be using a 21 pitch, the 23 is lowering the rpm but that's not helping
Boat might be water logged, weight boat and trailer at truck stop or other
Motor might be low on compression

Also is your tach accurate and speed using GPS?

Speed is via GPS the speedo is dead. The tach is good in my opinion. The mirage prop is what the previous guy put which looked good to me so I left it as is. But if 21 would be a performance increase worth the expense of a new prop I could get one.

My Rinker 232 (23ft cuddy) with same motor and 21P can reach 60 if things are right. I'm 3800

Or I should say it use to, I don't drive it much and rarely get it above 50 anymore

Why would not driving it much drop the top speed by 10mph? I would think after a 30min run the spider webs would be gone so to speak.
* But say I was to get a 21 pitch prop. Which model is my best chance to increase performance ( top speed) on my 454/bravo 1 deal ? Thanks

Just saying I haven't checked top speed in a long time, it might get there, just haven't tried. I have a larger top on it now

I'm just using the OEM prop that came with the boat when bought new, think its a Quick silver SS
Have a 19 stiletto used to pull skiers

I would find out if there is not other issues before going real deep (motor and boat weight)

Had a Nova 210XL with a 260HP 350ci Mercruiser (Alpha sized drive - before they called them Alphas).
Boat ran 44mph at 4400 with a 21P standard stainless 3 blade, 2 people, less than 1/2 tank of fuel. Would turn 4700-4800 ish with a 19P which we usually used for pulling 2 or 3 tubes at once (tube wars).
A friend had an "identically equipped" Chaparral 21 Cuddy which was always 3 mph faster (but would cavitate wildly in any attempt to corner at speed). The drive height was a little higher on the Chaparral and the hull weight was a little less, although the dimensions and silhouette of the 2 boats was virtually identical.

I know this is apples and oranges, but just giving you some reference. Smaller, lighter hull, less power.

I would expect a 330HP 23 foot Nova to run 45-50 mph. Wellcraft built those heavy.
Anybody have dfferent experience?

23 Nova 4000 23 Rinker 3800, that is heavier