Mercruiser 4.5L

[argonaut]

As many may know Mercruiser has dropped the Chevrolet based V6 to a purpose designed block.
More torque, better performance, much lighter.
An interesting point is that the 4.5L 200hp and the 4.5L 250hp are physically exactly the same - even down to heads, injectors & cam.
The only difference is the PCM mapping.

Wonder how long it will be before you can get it 'chipped' ... or even an app for your laptop to update the map.

One such firm already provides a 'cheat' upgrade, fools the map by spofing air temp sensor, the ARF is adjusted and engine gets richer mix (quoted 15% boost)

Maybe whole new modding industry will start.

[_Ed_]

Those 'chips' that fool the air temp must be avoided at all costs. Utter s***. I program race ECU's for a living and imho the IAT 'mods' belong in the dustbin. Proper remapping however is a whole different ball game, and when supplemented with proper modifications gets very real results indeed.

[Ianfs]

As many may know Mercruiser has dropped the Chrysler based V6 to a purpose designed block

And there's me thinking it was a Chevrolet block, or are they now one and the same? Or did they switch? It's difficult to keep up these days about who owns who!

[argonaut]

If I understand it right Chevrolet have ceased manufacture of the cast iron lumps ..... Mercury press release advised that they had their own block designed away from Chevrolet.
At least for what was the V6 4.3

[Ianfs]

So when did Chrysler blocks come about?

[argonaut]

Those 'chips' that fool the air temp must be avoided at all costs. Utter s***. I program race ECU's for a living and imho the IAT 'mods' belong in the dustbin. Proper remapping however is a whole different ball game, and when supplemented with proper modifications gets very real results indeed.

So there you are then - project for you go create a 200 to 250HP remap.


The type of systems that promise much without remap are these:
http://www.magnumtuning.com/en/detail/d ... -5l-200-hp

Not that I have any experience with them.

[ChrisH]

Switching the topic slightly.. how do you guys with mercruiser v6's get on with your trailer setup. I am really struggling to get any decent nose weight. The engine and outdrive are so far back it's impossible to get the weight over the axles.

Sent from my SM-G930F using Tapatalk

[argonaut]

No problem on my trailer.
Rear rollers just under transom ... and easy to get nose weight.
What nose weight you trying to set up?
Can always add a spare wheel onto draw bar.

[betty boop]

Switching the topic slightly.. how do you guys with mercruiser v6's get on with your trailer setup. I am really struggling to get any decent nose weight. The engine and outdrive are so far back it's impossible to get the weight over the axles.

Sent from my SM-G930F using Tapatalk

yes i struggle, I was light on the Pathfinder last year with a lot of bouncing, shifted the boat & winch post/roller forward but now Im not to sure its improved it for the kia. when she is level the front wheel of the double axle looks to take extra loading, the only way to test is buy a hitch scale but I havent got that far yet. Last keel roller more or less lines up with the drain plug but I have a LARGE swim platform over hang which Im convinced is affecting trailer and boat sea handling and getting me paranoid

[argonaut]

On my trailer, I move winch post forward about 4" from where it was , moved the rear Bogey's back so the last 4 rollers were just under the transom.

Did not have to move axles - but that would be an option.