looking to repower a speedster
 

New to the forum and well here it goes.
Got a new 2005 Speedster in 2006 and been running it since. Just when I purchased it the biggest motor you could get was the Volvo Penta 5.0(Chevy 305) Volvo SX 1.60 gear, and 14.?? X 21 prop. Now they offer a 5.7(350) with the same drive. I have a 383 in storage and can change it to marine specs. fairly easy. Well I guess the question I have is “is this a viable change?" will the mapping of the 350 work with the 383 like it did with my pickup? (1996 gmc yukon with the chevy replacement 383 see link http://www.crateenginedepot.com/stor...-P1583C53.aspx ) or would it be easier to sell the 305/Volvo drive and get into the mercury set up?
Sorry about so many questions right off the hit but the boat is almost paid for and just not fast enough to be called a speedster just yet. And the clowns I run with are just so much faster than me not looking to sell the boat just wanting to go faster.

update talked to a volvo mechanic the other day and he said he could remap my computer as long as he could get the unlock code from volvo. long story short volvo will not come off of the codes do to a warrantee issue. i then explained that i no longer have a warrantee and still they would not come off of the codes so i think i might just get rid of the boat and get something bigger.

first thing to me is having a paid off boat, gives you a little boost on the "bling budget"secondly the SX drive is strong and reliable. third, if you have an available 383 you could go carb, manifold and breakerless ignition, also, perf exh. for less budget than repowering. providing you have mechanical experience. you could then forget about the ecm altogether. and surely make an easy 400hp which should allow you to dust on some of your freinds. jmo

What about an aftermarket programable ECM like a MOTEC M800 or something similar. Ditch Volvo's entire ECM and tie your stock monitoring /vessel view system into that?