Any suggestions as to which 2" shortie
lower would be better suited on a 42' boat?
I've been told that the IMCO is suited better
on cats and large horsepower V's
Is the Sportsmaster a better choice on heavy
boat with approx. 600HP?
Or doesn't it matter?

I hear that the IMCO's are faster...

I am by no means an expert on this, but I have been doing some research on this subject. I am planniong on upgrading power to about the 600-650 h.p. range. But, before I do that ( and to help split up the expense) I am setting up the back of the boat first, ie: tabs, steering, drive. Tabs and steering have been done, so the drive is next. I have called a few sterndrive guys asking for their recommendations on the proper drive for my application, single engine 25' "V" bottom. I have told that my best bet would be a stock Bravo "XR", not one with an Imco lower. The reason I was given is that when the drive is trimmed up for speed, the angle of the cone of the drive would be pointed further down than would be a standard non-bulleted drive. This would cause extra drag.
Now this may be true for my application. Even with this increase of power, I would not be going anywhere near the speeds that some of you guys are going. The benefits or necessity of a bulleted drive might not come into play for me.
What do you guys think??

I was in a simular situation last year. I chose the sportmaster XR since I was going for 100MPH in a 26' single. Now I am planning on switching to a stock XR lower. I have found that I am losing speed with the extra trim I have to run on the sportmaster. Go with the stock XR. You will be faster and save some bucks. It just doesn't look as good on the trailer... So what!!!

For a 42' twin I don't think you can lose with the shorty IMCO or sportmaster. Cost is very close.

Look in parts for sale a guy Mv35 has a 35 fountain that picked up 4-5 mph with 2"shortys. May have been on fast boats site. Greg

Striken-Dennis
You missed one of the best deals on lowers that you could have found and I would have traded them "plus"for that old 96 Harley thats just sitting in your garage. After all, you cant ride two bikes at a time!!
and boat too!!
eliminator219

LES,

Can't do any of the above at the moment

Dennis
Look at the bright side, summer is on its way!!

IMCO has a 3" shorter lower, which will allow you to mount the engine lower - There may be other benefits - I needed the hatch clearance.