Proper prop for a Chris Craft Lancer Overnighter?

[72fj40]

I have a 1977 23ft CC Lancer Overnighter , when we found this basket case in a barn, the engine & manifiolds cracked. We rebuilt & marinized a 350sbc and married mercruiser cooling and and centerise exhaust manifolds to a Volvo 280 outdrive. We finally have the engine dialed in and were able to get mph & max rpm. I figure the engine is about 260-270hp, the volvo gear is 1.6:1. From research from this site the boat weighs in the neighborhood of 4000lbs. It is a deep V design. The prop that's on it is stamped michigan pr248, which i think is something like 14.3 x 23. At WOT we're at 4160rpm and GPS'd at 39 mph. I would think this engine should be turning closer to 4600-4800rpm? The Comp cams upper rpm range is at 5000rpm. Is there a better choice of prop out there. Many thanks to this website, I couldn't have put this beauty together without it.

 

[Bondo]

which i think is something like 14.3 x 23. At WOT we're at 4160rpm

Ayuh,.... Welcome Aboard.,.... A 21" prop might be enough of a drop to get the rpms up to where ya wanta be,....

I'm guessin' a 19" will probably be too small,...

 

[C. Lindberg]

72fj40,
The factory prop size spec'd by Chris-Craft for the Overnighter was a 14 3/8 x 19 LH but I agree with Bondo that a 14.3 x 21 (or 14.5 x 21) would be a good change especially considering you've increased the stock horsepower from 250 to the 260-270 you referenced (I'm assuming your AQ280SP is still turning left hand) Consulting my Michigan Wheel Prop chart I couldn't find any part no.s that correspond to that partial. BTW, the dry hull weight is closer to 4,400 lbs provided you still have all the Overnighter unique interior components vs. the 4,000 lbs noted in the CC Essential Guide.
FYI the 1978 Overnighter I restored (#137) was getting 42 mph at 4200 rpm w one passenger, full 50 gal tank using a 14.5 x 21 prop on an AQ280SP mated to the original, stock 350GLV Marine Power engine.
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[72fj40]

Thanks, Bondo & C. Lindberg for the replys, I figure 21 pitch might be the way to go. I'll try to track 1 down. I was able to cross the mich # to their numeric # of 082061 which is 14.375x23.

C.Linberg, I have run across you're Overnighter several times in my google searching for info on these boats. You have one mighty fine ride. I think our hull is # 96. The engine was painted white and it was the 300hp, 350FLV std rotation. We have most of the interior pieces. We will be redoing it in the next year or so. This project will probably be more of a resto mod restoration. .