350 Mag performance upgrade suggestions
#21
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Originally Posted by blowncrown
It's a 22 1/2' Crownline bow rider. Ran just over 50 mph gps with a 19p Mirage Plus and now run a 23p at just over 63. Still had some issuse with timing and rev limitter last time out, should be able to get 65mph with a little more tuning. I have plans for manifolds and higher boost this summer, shooting for 70mph.
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Originally Posted by justinVIP
How do you get ahold of Tyler Crockett in Michigan? Thanks
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Justin: I went through that with my '03 350 mag. before I upgraded to a 496HO. The '03 ecm is the 555 ecu that no one other than Whipple presently has the ability to reprogram. There were rumours, though, that other shops were working together on "cracking?" the code. Maybe Dustin at Whipple can help you; they do offer ECM reprogramming on the 555 ecu on the 496s.
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Originally Posted by bobl
If you're willing to ditch the factory EFI and go with an aftermarket system or carb you can get another 75 HP (per engine) or so naturally aspirated. Otherwise leave it alone. More than that, put a pair of Whipples on it.
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thanks everyone for your answers to my questions. My boat would need some serious upgrades to be able to put on a Procharger. I have the 350 Mag Mpi, but only the Alpha outdrive. It is a 2102 VIP Victory bowrider. It is a very deep and extra wide boat. It does pretty well for its size I think though. Right now I run about 59 GPS 63 speedo. (I like to go by the speedo number, it makes me feel better
) I should probably just get a labbed prop. I am running about 4850-4900 RPM. Right now I have a Ballistic prop. It seems to work well with this boat though. My boat is a little bow heavy. It seems hard to get the lift that I need. Here's a couple pics.
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#27
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justin- did you have any luck talking to Tyler Crockett??......I forgot , he is a member here.....If its bow lift your looking for try a Mercury Mirage or Mirage Plus prop.....they offer tons of lift and will fit on your Alpha, though because of the increased diameter of the prop you will have to ditch the stock trim tab (at the end of the cavitation plate) and go with a flush one (its a Merc part)......and you should be putting a Simrek drive shower on that Alpha too if you are up on plane for long periods of time......the increased dia of the Mirage will load the drive more and the Alpha runs hot as it is........I have twin alphas and smallblocks on my boat.......been there.........doug
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Doug, could you elaborate on the trim tab you are talking about behind the cavitation plate? I've been told to go with a mirage plus before, and possibly have it labbed. (Houston Prop possibly) What I don't understand is how you can just order a labbed prop without knowing how it is going to respond to your boat? I suppose I would need to test a Mirage prop, and then try and figure out how much RPM I would gain by labbing a prop. This part you are talking about. Where exactly is this, and how much is it about? I was deifinitely going to go with Simrek drive shower as well. Cheap insurance I guess. We do run wide open on the river quite a bit.
Thanks for your help. BTW, I haven't talked to Tyler yet.
Thanks for your help. BTW, I haven't talked to Tyler yet.
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I had a brain fart. sorry. I think you are talking about the round disk on the bottom of the cav plate. Mine has the flush one already. Thanks, J.
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talk to mark boos from precision marine he did an awsome job of reprogramming my ecu for my 1998 502 efi !!