Originally Posted by Fr. Frank
Sandy, Some possibly relevant data concerning power options for this boat:
Back in '86 Wellcraft built 3 prototype 26' Scarab Sport center consoles that were long and narrow like your new boat. They were 26'1", and only had an 7'8" beam.
Among the prototypes, there was 1 transom-mount outboard model, 1 Armstrong bracket-mount outboard model, and 1 stern-drive model.
The view of the hull from the stern looked almost identical to the boat you're having conniptions over (rightfully so).
The only difference I remember was a small pad at the keel, perhaps 10" wide, running forward from the transom about 8' - 10' . Dead-rise at the stern on the inner planing surface was 24* with a 2" flat before the inner hard-chine, then the outer planing surface was 20*, with again with a flat before the hull side.
The bracket-mount was built to accept either single or twin OB, and we tested it both ways, with a variety of power configurations. We tested single Yamaha 200 & 220 hp 60* 2.6L, and 225 hp 90* 2.6L motors, and single Mercury 200 & 225 2.5L, and 275 hp 3.4L motor. We also tested twin Yamaha 130 V4 and 150 hp V6 motors, and twin Mercury 135 hp 2.0L and 200 hp 2.5L motors.
First, ALL the single outboards were EXCEEDINGLY squirrely at 40+ mph in anything over 2' seas.
Second, even with the keel pad, because of the "P-factor", above 60 mph in flat-calm mild chine-walk was an issue with the single 220 Yamaha and 275 Mercury.
Top speed with the Merc 275 on the bracket was 65 mph in flat water, and 67 in a moderate chop. I think top speed on the same transom-mounted was about 60-61 mph.
Top speed with the Yamaha 220 "Excel" was 61 in flat water, and 64 in a moderate chop. Top speed on the transom was 56 mph.
And while the Yamaha 225 could just touch 60 mph in a chop, it never got over 60.
Counter-rotating twins were a LOT more stable at all speeds than the singles.
Twin bracketed setup with the Merc 200's was marginally the fastest configuration, with a consistent top speed of 69 mph in a light to moderate chop. (although the radar gun briefly showed 70 in a light chop downwind :-) )
Twin 135's Mercs showed only 50 mph at WOT.
Twin bracketed Yamaha 150's showed a top speed of 55 mph, but the 800 lbs hanging off the bracket was untenable, and slow speed maneuverability suffered greatly. With the twin V6 Yamaha motors, the hull would rise to a 47 degree angle while accelerating to plane, completely obscuring forward vision for 5-6 seconds. It was the slowest to plane setup of all we tried.
The twin Yamaha 130's showed a top speed only 2 mph less than the twin 150's, at 53 mph, and was faster to plane than anything except the twin Merc 200's and single Merc 275. It also was the best handling setup on plane in 2'-3' seas, giving the greatest amount of control and least instability.
(We actually took the boat fishing while it was rigged with the twin 200 Mercs, and it rolled like a pig drifting in 2' seas, until we rigged a stabilizer using the anchor and a 150 qt cooler lid off the windward side to slow the roll).
In my opinion, the twin 130's on the bracket was the best config we tested, and Wellcraft's subsequent decision to limit the boat to a recommended 275 max OB hp reflected the results of our tests. They also decided to not put into production either the transom mount OB or stern-drive versions of the 1987 26' Scarab Sport center-console, and produced only 12 of the 26' Scarab Sports for 1987, discontinuing the model halfway through the '87 model year. We had one on our lot for sale with a single 220 Excel for over 2 years before we finally sold it.
The same hull was produced as a cuddy-cabin in '87 and '88 as a 300 or 350 hp single stern-drive model and was called the 26' Scarab Excel.
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