What if you had a older 26-27 foot formula, chris craft, that was set up for twin engine small blocks. How well do you think it would perform with a single engine big block? Or do you think the boats are just to heavy for this.

it was designed with twins for reason.

eitehr slap some blowers on those twin SBCs or see if you can sqwash some big blocks in

Put in a couple of 377" Horizons !! Should be a rocket!!

Boomer,
I tried my boat (26 Sutphen) in both single and twin before I bought. Both were used (12 years old) and had stock power, the single was a 330/TRS and the twin was 350 Mag/Alpha's. Simple choice - I bought the twins because I planned to stick with stock power, more or less.
To move the single at a comparable speed to the twins, my guess is it would need 50 per cent more horse power than the 330 was delivering, something like a 502. In round figures, add 7 - 10 thousand dollars to the price of your old used boat.
Buying the same boat new, I would go with a single and I doubt that the construction/weight has changed much. What has changed is the more affordable power options available from Mercury.
Check with the manufacturer to see if they offered a single engine option. You can bet that a twin big block/Bravo combo will be very heavy in that size boat. If my engines blow, I will look into stroked sbc's with as much aluminum as I can afford because I hate extra weight.

also old formula's are biult like tanks. Your not goign to get much speed out of a 330 454. YOu woudl need BIG power. I had a single 330 in my older (heavy) scarab (26 excel, 27' oal) and she barely ran 50 with 330hp. I have a 550hp that is abotu to be dropped in and i am shooting for mid/high 70s.

coincidentally if you interest teh baot is for sale. It shodul be backl together shortly. e-mail me i'd like to deal on it [email protected]