7.4 mpi vs the "replacement" 383?
 

In a 23.5 ft bowrider, 12 years old. Only 200 hours on the 7.4.
If you HAD to, would you find a long block 7.4 to put in where the old one was, or this mercruiser 383 replacement?
http://www.perfprotech.com/store/pro...R80,66327.aspx

I may not have a choice in the matter, as I did not winterize the 7.4.:eekdrop: (someone else did)



But, if it were your boat, would you kick in the extra cash to get a new rebuilt mercruiser, or find a rebuilt longblock 7.4, and switch all the accessories over?

We do a bit of tubing, some water skiing, etc. Prety sure I would get better economy out of the mouse motor, but wondering if I would miss the torque?

There is this article which makes a pretty compelling argument for the mouse:
http://www.stingrayboats.com/product...ws/tb2_99.html

We frequently have 9 or 10 souls on board. (boat rated for 12)

The quickest (shortest turn around time) solution is the plug and play 383.

However,..

I would look into how big of a motor you could build in a big block for the $9k you'd spend on the crate motor. The advantage being all the accessories already in hand. With a 23.5' boat in the long run a big block would be the way to go.

first, where do you live. this winter was pretty mild on the east coast. second, you can find an article on the internet that will defend any position and make it sound reasonable and sensible. for $9k i am sure you can find a plug-play 454. you can find all kinds of good used for a lot less. especially here... and yes, you would miss the torque.

I did a Sea Ray that had a 7.4 Bravo I. I installed the 357 and not the 383 and only lost 400 RPM. The customer states that no other noticeable difference. The 383 would be a nice replacement.

While mild, we still got sub zero for a while.. Enough to cause heartache.

Upstate NY. The 7.4 only a little over 200 hours on it. It (and the boat) were kept mint. I am a little leary of a used one. I have a friend with the exact same engine in a 28' sunsation, and he desperately would love to upgrade to something with more power. He has two power settings on that thing, one is idle. So I would be thinking a used one would come from a similar environment/ reason.
In the end (unless I start *****ing, and I really don't want to have to) my hands are tied, the shop will do what they think it takes to make it right. I want to go into it as educated as possible though.

Find out what all is damaged on the 7.4. No matter what, Start There!

I'm pretty sure my engine is shot. Asking around, no shop has a memory of casting plugs getting ejected and NOT having a cracked block.
I will pleasantly surprised if that is not the case, but I am not holding out much hope. I think somehow the engine did not get winterized, or if it did, it certainly did not get done sufficiently.

I had two friends that both had same brand, near identical 21' deep V powerboats. One was powered by a 350 Mag. The other had a stock 454. 270 H.P. V 330. The 454 boat was 8 m.p.h. faster.

I have twin 6.2s (377cu in) in my current boat. They are nice motors but there is no inexpensive horsepower out there for these motors if you find you've come up a bit short.

I'd be tempted to stay big block (new long block) and add fresh water cooling.

I love that idea. Would make winterization simple and sure.