350 MPI MAG Rebuild Plans - Tips & Info from Vets
#1
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Greetings. I need input from veterans. I'm trying to develop build plans for my 2001 Mercruiser MPI MAG Ski. It is a 315 HP rated motor. This is my first marine build, but I've done several high HP automotive engines including a very nice 388 stroker.
My objective:
Motor is for my 2001 Tige 24" wakeboard boat. So I'm focusing on hole shot or pure low end torque for pulling. Also, it is a budget rebuild. I'd love to build a 400 HP motor if possible but would be happy with a 330-350HP build. I'm not trying to make this a heavy financial investment.
Need help understanding:
Ideally, I'd like to do a 383 stroker motor. However, I want to avoid a large investment in upgrading the EFI system (ECM programming, injectors, etc), intake & exhaust manifolds, etc. I don't mind spending an additional $500-750 or so in this area but know manifolds can be crazy expensive. I can do custom porting myself so that's an option but spending big bucks on aftermarket manifolds is probably out of scope for me.
Questions:
Can automotive 383 stroker kits be used for marine applications?
What other mods or upgrades would be required to meet the increased air/fuel demands of a stroker kit?
Other suggestions? Tips for a budget rebuild?
My objective:
Motor is for my 2001 Tige 24" wakeboard boat. So I'm focusing on hole shot or pure low end torque for pulling. Also, it is a budget rebuild. I'd love to build a 400 HP motor if possible but would be happy with a 330-350HP build. I'm not trying to make this a heavy financial investment.
Need help understanding:
Ideally, I'd like to do a 383 stroker motor. However, I want to avoid a large investment in upgrading the EFI system (ECM programming, injectors, etc), intake & exhaust manifolds, etc. I don't mind spending an additional $500-750 or so in this area but know manifolds can be crazy expensive. I can do custom porting myself so that's an option but spending big bucks on aftermarket manifolds is probably out of scope for me.
Questions:
Can automotive 383 stroker kits be used for marine applications?
What other mods or upgrades would be required to meet the increased air/fuel demands of a stroker kit?
Other suggestions? Tips for a budget rebuild?
#3
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Why reinvent the wheel? Click on the Scorpion tag in the lower right hand corner.
http://sites.mercurymarine.com/porta..._schema=PORTAL
http://sites.mercurymarine.com/porta..._schema=PORTAL
#4
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I am by no means a professional, I do car stuff too. But I will tell you, you can use the same cranks, rods, and pistons as the car stuff.... the difference is gonna be in the tolerances when setting up everything. The problem with FI stuff is this... anytime you make more power, usually the injectors and tuning are required to be upgraded. I would think if you only made 330-350hp, the stock injectors MIGHT be ok, but the tuning will definitely be required.
I would say for 400hp you are gonna need bigger injectors and a re-tune.... if the new injectors will even work with your current FI system.
I would say for 400hp you are gonna need bigger injectors and a re-tune.... if the new injectors will even work with your current FI system.