Boatmad.com


Reply
 
Thread Tools Display Modes
 
Old 03-02-2012, 10:23 PM   #1
Registered User
 
leeornsby's Avatar
 
Location: Sarisbury Green
Occupation: Electrician
Interests: Racing
Boat make: Ring 34
Engines: Mercruisers
Cruising area: Solent

Join Date: Dec 2009
Location: Sarisbury Green
Posts: 405
Mercruiser 5.7 mpi

Hi all, I'm after a bit of advice, does anyone know if there is any way to get extra hp from a 5.7 350 mag mpi without costing the earth. Its going to be put in a Rinker 236 with side exit exhausts.

Thanks Lee.
__________________

leeornsby is offline   Reply With Quote
Old 03-02-2012, 10:34 PM   #2
green army
 
neal_skyline's Avatar
 
Country: uk
Location: southampton
Interests: cars/boats/pub
Boat name: 1-52
Boat make: formula,no more tint sh?t
Engines: mercruiser v8
Cruising area: solent/iow

Join Date: Jul 2008
Location: southampton
Posts: 355
Send a message via MSN to neal_skyline
cash for power only,its a boat
__________________

__________________
watch what you buy off mates
neal_skyline is offline   Reply With Quote
Old 03-02-2012, 10:39 PM   #3
Registered User
 
leeornsby's Avatar
 
Location: Sarisbury Green
Occupation: Electrician
Interests: Racing
Boat make: Ring 34
Engines: Mercruisers
Cruising area: Solent

Join Date: Dec 2009
Location: Sarisbury Green
Posts: 405
Hows racing going, see your boat sitting outside bursledon outboards, also had any takers on Dan's ring 20?
leeornsby is offline   Reply With Quote
Old 04-02-2012, 10:19 AM   #4
Registered User
 
Country: United Kingdom
Location: Dorset
Occupation: Marine Engineer
Interests: Driving boats fast, wakeboarding and boating to pub
Boat name: none
Boat make: Ring 20, 17ft Plancraft Sabre
Engines: Mariner 200 2.5, Yamaha 115 V4
Cruising area: Poole

Join Date: Aug 2009
Location: Dorset
Posts: 70
Send a message via MSN to odjsabre
Good old fashioned tuning.....

Open up the ports a bit on the cylinder heads and fit a performance camshaft.
If you feeling flush upgrade the standard mercruiser manifolds and get some descent performance headers for it.

It will all help to improve air flow and increase power.

Oli
odjsabre is offline   Reply With Quote
Old 04-02-2012, 10:34 AM   #5
Registered User
 
Tony Davis's Avatar
 
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath

Join Date: Mar 2004
Location: In a box
Posts: 5,201
Buy a bigger motor!
__________________
Chaos for Moderator.
Tony Davis is offline   Reply With Quote
Old 05-02-2012, 10:51 PM   #6
Registered User
 
Country: Belgium

Join Date: Sep 2005
Posts: 93
^^^^^^ what he says
Raffshore is offline   Reply With Quote
Old 05-02-2012, 10:55 PM   #7
Registered User
 
leeornsby's Avatar
 
Location: Sarisbury Green
Occupation: Electrician
Interests: Racing
Boat make: Ring 34
Engines: Mercruisers
Cruising area: Solent

Join Date: Dec 2009
Location: Sarisbury Green
Posts: 405
Do you know the cost of a set of headers? Or have a set?

Thanks
leeornsby is offline   Reply With Quote
Old 06-02-2012, 12:01 AM   #8
The Doc
 
Captain Chaos's Avatar
 

Join Date: Mar 2004
Posts: 8,265
headers as a stand alone upgrade arent likely to do alot
Captain Chaos is offline   Reply With Quote
Old 06-02-2012, 09:05 AM   #9
Registered User
 
Tony Davis's Avatar
 
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath

Join Date: Mar 2004
Location: In a box
Posts: 5,201
Quote:
Originally Posted by leeornsby View Post
Do you know the cost of a set of headers? Or have a set?

Thanks
Around £3-3.5k
__________________
Chaos for Moderator.
Tony Davis is offline   Reply With Quote
Old 09-02-2012, 08:27 PM   #10
Registered User
 

Join Date: Oct 2011
Posts: 19
How are you getting on with it Lee?
madrat is offline   Reply With Quote
Old 24-02-2012, 01:37 PM   #11
Registered User
 
Pulse8's Avatar
 
Country: Netherlands
Location: @ home
Occupation: Engineer
Interests: I like Wolffs in schaepclothing
Boat name: Pulse8
Boat make: DORAL/7,6m/ 245 ESCAPE, elite series
Engines: Procharger Volvo Penta 5.7GXI about 490HP

Join Date: Feb 2012
Location: @ home
Posts: 28
Send a message via Skype™ to Pulse8
Quote:
Originally Posted by neal_skyline View Post
cash for power only,its a boat

He's right


Quote:
Originally Posted by leeornsby View Post
Hi all, I'm after a bit of advice, does anyone know if there is any way to get extra hp from a 5.7 350 mag mpi without costing the earth. Its going to be put in a Rinker 236 with side exit exhausts.

Thanks Lee.
Some headers combined with AFR hi performance alu heads will do it.
but will cost you about 3500.
combined with a bit of ECM tune would be perfect.
but there arent to much guys who knows how to.

Dit some mods myself but costs are about same as a new block
But I always take another path.
I did put on a pair of HITEK headers, and a procharger and reached a 14,5 knot increase in topspeed.
Power is around 490HP out of this small block and is max reliable for this engine block.
I have a DP-SM drive who can handle this power.
On a stock mercruiser alpha or bravo3 drive its a matter of waiting they fail
with another crank and pistons it could be 540HP /5200rpm
Attached Thumbnails
Click image for larger version

Name:	IMG_2664b.jpg
Views:	137
Size:	104.3 KB
ID:	33731   Click image for larger version

Name:	IMG_2673b.jpg
Views:	142
Size:	118.9 KB
ID:	33732   Click image for larger version

Name:	Afb0006.jpg
Views:	143
Size:	160.8 KB
ID:	33733  
__________________

__________________
I like to go fast but my wife always thinks otherwise who is still searching for a brake pedal
Pulse8 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Powered by vBadvanced CMPS v3.2.3

All times are GMT +1. The time now is 06:02 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.