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Crusader 350XL into a stroker motor?

H

herdbull2

New member
I own a 1980 31 Tiara open. I bought it from a guy on the east coast. He had it repowered with Marinepower throttle body injected 350's. The boat was in rough shape. I have been restoring it.

During my restoration efforts, I bought a second Tiara. This one is a 1984 31 Tiara Open that had been damaged in Hurricane Sandy. This boat came with twin Crusader 350XLs. I have demo'd the boat out completely and saved what I wanted. Obviously, I saved the motors and transmissions.

So, the boat I am using and restoring currently has the Marinepower motors in it. Same size as the Crusaders I have in my garage. I am thinking that maybe it would be cool to have the Crusaders built into 383 Stroker motors pushing 400 plus HP and then putting them in the boat instead of the Marinepower engines.

Seems to me that the extra horsepower would certainly be felt in the performance of the boat. Further, seems like my fuel economy would go down because I think more horsepower will require more fuel. I know the carbs on the strokers would be 750 cfm rather than the 650 cfm.

My buddies think I am nuts and I will be loosing reliabity and effectively ruining those Crusader motors. (I think they are just jealous that I have the option) hahahahahha.;)

I am interested in everyone's thoughts?

Also, if you think Stokers would be a cool way to go, any thoughts on where to have them done at? I have a bunch of back yard mechanic beer drinking buddies of mine saying.... "just bring em over here, we can do it in my garage". And, if it was a 1985 camero, I probably would. But, this is my boat. So, not sure having my buddies help and do this ourselves is a great idea. Granted, I understand the machinest does the tricky work. But even so, I think I am leaning toward finding someone who actually "builds 383 Strokers for marine applications" professionally.

Thoughts?
 
That hull has a lot of "wet area" and you won't find any substitute for cubic inches...

A stroker will help but not like a big block. 400hp? - maybe at wide open throttle but not likely at cruise... And there's NO reason any SBC stroker needs a 750 cfm for an inboard application...FWIW, don't do all the "street rod" engine builder tricks and the vast majority won't help most boat engines...you want to build as much torque in the lower rpm band as possible...
 
I'd be OK with the 6.3L's ( 383s ).
But there is a caveat to this. DO NOT build with the GM style full dished pistons!!!!
You'll want to incorporate a quench area of approximately .038" to .040", and use a cylinder head/piston profile combination that renders a suitable static compression ratio.
This is particularly important for a 6.2 or 6.3 (377/383 cu in) SBC!

Take a look at this thread beginning at post #7!
http://www.marineengine.com/boat-forum/showthread.php?394668-V6-to-V8-engine-swap&p=455084#post455084


This is not a Hot Rod build!
This is a build that helps with LPCP (better torque) and helps greatly against detonation potential.
This also allows for a slightly higher static compression ratio, and will give this engine much greater torque.

Fuel economy is typically improved also.


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If you go through all that trouble and $$$, you'll find that the boat performs about the same (assuming the present motor is in decent shape). Seen this when people upgraded to more powerful engines.

Jeff
 
I agree with Jeff. At the price that fuel is and will be why go through the cost and hassle and only to find your running costs are up and the performance is the same? There is a formula with which you can figure what the top speed your boat is capable of, and I would bet the factory set the boat up that way
 
Guys, the OP made this comment;

"So, the boat I am using and restoring currently has the Marinepower motors in it.
(I assume that he means 5.7's)
Same size as the Crusaders I have in my garage. I am thinking that maybe it would be cool to have the Crusaders built into 383 Stroker motors pushing 400 plus HP and then putting them in the boat instead of the Marinepower engines."

First of all, a 400hp build would not be recommended!
You'll want to build torque into these engines....., not necessarily high horsepower.

Secondly...... Don't let your beer drinking back yard mechanic buddies be involved in this Marine build!!!!




As I see and read this, he's asking about the possibility and feasibility of building a pair of 6.3L (383's) SBC's from his current 5.7's!

In my opinion, if you're going to do this....... Do It Right by steering completely clear of the GM style full dished pistons!
The extra cost for the correct pistons won't break the boat bank!


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