Merc 520/ 540 / 565 General Info and Power numbers

Reply Subscribe

Thread Tools

02-04-2022, 01:45 PM

#21

DRAG

Platinum Member

Thread Starter

Join Date: Jul 2015

Location: Danville, IN

Posts: 419

Likes: 157

Received 333 Likes on 124 Posts

Quote:

Originally Posted by cheech

Just so I'm following you.
You say you run your Superflow. Are you an engine builder?
The 520 is just the old 502 based architecture right?
What's the price of a 520 longblock?
Couldn't you put some stout "base"engines of all aftermarket components together for way less and swap your accessories over?
Speaking of which, the 520 appear to have the 525 plenum. Weren't those handicaps once a certain threshold power wise was reached? The 565 I see has the flame arresters on top, so not sure what they have going on under that cover.

You get OEM Merc rods?

I do build engines, but nothing like this and never plan to. I only posted this for info and discussion on the stock Merc engines and to consolidate some info for others that search. I think if Merc put a little more info out there they would sell better....performance minded people like the details. The DTS is so damn good, I'd never go back.

I ordered rods and a few other pieces a couple months ago. Supposed to deliver before end of Feb. I'm just curious to see what kind of I-beam we are looking at to see if it could handle some boost. Lets just say that "hypothetically" the rods were made by someone like Trip Manley...and not saying they are. Just an example. They have an entry level sportsman I-beam rod, an H-beam rod, and a Pro Series I-beam. I know I regularly put 175hp per rod through a single H beam and 250-300hp through a Pro Series. Based on price I'd say its the entry level, but we shall see.

Last edited by DRAG; 02-04-2022 at 01:56 PM.

The following 2 users liked this post by DRAG:

cheech (02-06-2022), SB (02-07-2022)

02-04-2022, 01:47 PM

#22

DRAG

Platinum Member

Thread Starter

Join Date: Jul 2015

Location: Danville, IN

Posts: 419

Likes: 157

Received 333 Likes on 124 Posts

Quote:

Originally Posted by KWright

stock 525 ran in complete boat trim. With wet exhaust.

Thanks for sharing. That is pretty strong.

02-04-2022, 02:30 PM

#23

F-2 Speedy

Platinum Member

iTrader: (6)

Join Date: May 2012

Location: Midwest & T-Rock

Posts: 10,436

Likes: 414

Received 3,079 Likes on 1,364 Posts

There probably Manley H beam like whats in the 525 that have Mercury Racing stenciled on them.

Last edited by F-2 Speedy; 02-04-2022 at 02:45 PM.

The following users liked this post:

DRAG (02-04-2022)

02-04-2022, 03:23 PM

#24

Wildman_grafix

Registered

Join Date: Jun 2007

Location: Merritt Island, FL

Posts: 6,653

Likes: 1,163

Received 1,332 Likes on 743 Posts

Both ran on the same Dyno full marine trim, power steering, water pumps, CMI exhaust etc. Superflow Dyno, list as "Standard Corrected Power". Not sure what standard was used.