From mild to wild! Building a 540 or 572?
09-06-2011 | 10:11 AM
#11
Platinum Member
Joined: Jun 2004
Posts: 7,320
Likes: 1,039
From: frankenmuth michigan
I have a 540 with the stock intake and fuel injection setup off a 454 mag mpi(should be the same as yours) makes 575hp. I have talked to 3 of the top engine guys on this site and they have all said the same thing, that is all that the intake will flow. All have recommended ditching the stock intake and installing a Holley or FAST efi setup. They claim a 50hp gain just by changing intakes. I plan to swap mine out this winter.
Mine runs great and is a HUGE improvement over the 454mag, but will only turn 5200 rpm no matter what prop i put on it. Something to consider.
Mine runs great and is a HUGE improvement over the 454mag, but will only turn 5200 rpm no matter what prop i put on it. Something to consider.
Last edited by articfriends; 09-06-2011 at 01:11 PM.
09-06-2011 | 10:47 PM
#12
Registered
Joined: Aug 2010
Posts: 2,233
Likes: 550
From: Cape Coral FL
My intake , throttle body and injectors are bone stock as delivered from Merc. I think in the long run it will be better to upgrade as opposed to doing all of the work to the existing setup.
I intentionally kept my 540 very mild because i also am running a stock Bravo 1. I have since purchased an XR upper and am IMCO lower, so i am not afraid to make a little more power. I hate to rip my fresh(20hr) engine back apart, but you have to do what you have to do.
I intentionally kept my 540 very mild because i also am running a stock Bravo 1. I have since purchased an XR upper and am IMCO lower, so i am not afraid to make a little more power. I hate to rip my fresh(20hr) engine back apart, but you have to do what you have to do.
Last edited by snapmorgan; 09-06-2011 at 10:55 PM.
09-06-2011 | 11:21 PM
#13
Registered
Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
[QUOTE
Mine runs great and is a HUGE improvement over the 454mag, but will only turn 5200 rpm no matter what prop i put on it. Something to consider.[/QUOTE]
Sure you're not hitting the stock rev limiter?
Mine runs great and is a HUGE improvement over the 454mag, but will only turn 5200 rpm no matter what prop i put on it. Something to consider.[/QUOTE]
Sure you're not hitting the stock rev limiter?
09-11-2011 | 08:11 PM
#19
Thread Starter
Registered
Joined: Jul 2011
Posts: 126
Likes: 0
From: Pensacola FL
The build has went toward a whipple 2.3L unit. Also adding a set of stainless marine exhaust. Any more HP than that a I'll need a new upgraded outdrive. I will need a lower unit soon. How do I know if I need a shorty lower unit?
Thanks
Thanks
