| Author |
Message |
   
ERIC PAUL
Member Username: ep_brooklyn
Post Number: 7 Registered: 04-2008
| | Posted on Wednesday, September 16, 2009 - 11:32 am: |
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Hi everyone, I have a 1976 chrysler LM318 225HP in my 26 foot silverton. I was thinking of repowering by putting a bigger chrysler engine in (possibly chrysler 440) but I have heard rumors you can destroy the V-drive because of the added power/torque that would come from an increase in HP. Would anyone happen to know how high I could go in CID or horsepower without having transmission problems? Any help would be appreciated. Thanks, E! |
   
Fastjeff
Senior Member Username: fastjeff
Post Number: 6785 Registered: 09-2003

| | Posted on Wednesday, September 16, 2009 - 02:00 pm: |
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Most boats powered by small block Chryslers were offered in BOTH the 318 and 360 options. Can't be positive, but I'd e stunned if the 360 used a heavier drive train. The same can't be said of the 440 (though they MIGHT use the same one as well). The problem with going that was is that everything about the 440 is different from the small block--mounts, electrical connections, flywheel, bell housing, etc. etc. A good, well built 360 makes at least 275 hp. That should move your boat along really fine, and not cost you a fortune to install. Jeff |
   
G. Harrington
Member Username: bogdenz
Post Number: 52 Registered: 06-2009
| | Posted on Thursday, September 17, 2009 - 04:18 pm: |
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I know it's not addressing the question at hand but, I have to second Jeff's comments about upgrading to a 360 vs. the 440. The 360 weighs substantially less than the 440 and, as Jeff eluded to, it shares the majority of parts/components with the 318.....so your current engine would provide you with most of what you'd need to build out a 360 long block (sans oil pan and a couple of other pieces). I also agree with Jeff's "at least" 275hp. If you wanted to put a couple of extra bucks into building a 360 (cylinder head work, etc.), you could bring it right up into the ball park of the 440's factory HP (330'ish). |
   
Dan Finnelly
Member Username: tolly_family
Post Number: 81 Registered: 07-2006
| | Posted on Thursday, September 17, 2009 - 05:13 pm: |
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Someone correct me if I am wrong but I think small blocks had a 71C transmission and big blocks had the 72C. Dan |
   
bob dice
New member Username: bojibob
Post Number: 2 Registered: 09-2009
| | Posted on Friday, September 18, 2009 - 11:44 pm: |
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I have 26ft Silverton express criuser with upgraded 360 engine. Used same paragon v-drive and works fine with tranny. I have 440 in my other boat and had the same thoughts, but my friend mechanic informed about the cost of changing everything. |
   
PF Herzog
New member Username: peter_h
Post Number: 1 Registered: 09-2009
| | Posted on Saturday, September 19, 2009 - 12:08 pm: |
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Eric: The 71C is rated to only 310 hp in a gas engine. If you upgrade to a 440 cu. in. which is 330 hp you would be risking a blown tranny unless you also upgraded to the 72C which is rated to 475 hp. |
   
Russell Smith
Member Username: loid58
Post Number: 53 Registered: 07-2007
| | Posted on Tuesday, October 06, 2009 - 12:52 am: |
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depending on the vee drive, you could blow it up. I seem to remember that the walter vee with the small block is rated to 275 hp. So make sure that the trans/ vee combo you're using is rated for the hp you expect to finally have. |