Sceptre 20 I/O Repower

[ericallen01]

Hello CSCers

Been running my 1975 SC20 for a season with an 1990's 5.0L/Alpha One setup. It's a great hull, is nicely powered and handles well on plane. I put on Bennett Tabs also to improve planing.

However the engine weight (est. ~940lbs with outdrive) seems a bit much for the hull. The boat sits stern heavy, with the stern cockpit sitting 1-2" below the waterline. I'm not too confident to leave the boat moored overnight with the scuppers open. Boat is otherwise stock.

With the hull + transom in great condition, I'd like to do a sterndrive repower and wondered if anyone had looked at weight-power in the I/O category for these hulls.

I did see some V8 options in the SC catalogues for 20' hulls.

Today, the 3.0L vs. 4.5L seem like the most relevant options, but I'm open to advice.

Would putting in a 3.0L leave me seriously underpowered?
Is the V6 a poor tradeoff to save 120lbs?
Are I/O's a poor choice today for these hulls given outboard/bracket combos?

Thanks in advance!


Advertised Mercruiser engine weights (excl. 70lb alpha one)

Reman
350 MPI Alpha 932
357 Alpha 4V 871
4.3L Alpha 4V 784
3.0L Alpha TKS 567

New
4.5L 250hp ECT 761
4.5L 200hp ECT 761
4.3L MPI ECT 220hp 775
4.3 TKS 725
4.3L MPI ECT 180hp 775
3.0 TKS 455
3.0L MPI ECT 515