I recently bought a 1975 Magnum 27 Sport which was built with a twin Volvo engine setup and then converted to a pair of Mercury Bravo1 drives using aluminium plates cut to the profile of the Volvo transom plates. It also had some very nice Stainless Steel cover plates over the original exhaust outlets all of which had to go in my book so I could revert to a clean transom with new wood inside. This now leaves me with the option to also change the "X" diamention if required. So is anyone running a 27 sport
with twin Bravo 1`s and a pair of 350 ci SBC. with 350Hp a side @ 5600 RPM. following a nice new freshen up. If so please can you tell me the "X" diamention and also the Prop. size. This boat is stricktly for fun not racing at any level, so easy on the plane and a comfortable cruise speed is all that is required please ( well this year anyway ! )

I know this is months old a x of 16 to 16 1/2 would be around a propshaft height of 5'' below. you could ask in the other forums tech section and ask in QA but 4 1/2'' to 5 '' is a medium height old heights were 7 to 7 5/8s''

Thank you for thinking of me but I had to move on and after a great deal of debate I went for 32" centres and 16.5" up plus a restroke up to 383ci with a 9.5 to 1 compression ratio. The cam is so-so mild and will run up to 5800 Rpm. So what would be you bet for the speed range with this set up then ?

Whats the 383 gonna make?

The engine builder tells me a solid no fuss 400hp per side.!!!!
What would you think ?