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Discussion Starter #1
I have an aussie 302C that I have converted to a 351C with the crank and rod change. I have read that the longer rod has definite piston dwell advantages. What if if I was to use a 302C rod on the 351 crank? Has this been done - Is there a high pin position piston available? Granted there would be no extra cubes but would it be a good build combo a better motor that zings to 6000 perhaps 6500rpm? Would ther be any real value in such a hybrid?

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<font size=-1>[ This Message was edited by: speedar on 4/5/02 6:18am ]</font>
 

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I think there was an article about long rod engines vs. short rod engines on the archives. A buddy of mine races sprints, and at that horsepower level (around 840), the difference between a 6" rod and a 6.125 rod is minimal..usually around 5-10 HP. Both engines are identically built, even the pistons weigh the same. It kind of leads me to believe that it's not worth the extra time/money at street horsepower levels to build the long-rod engine.
 

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Im from austrlia and here
thats a common conversion
351 crank
302 rod and
an off the shelf
ACL piston
same goes for a 200/250 6 cylinder combo
dont know much more than it allows the engine to produces more revs easily (less piston speed) and the piston spends less time trying to push itself through the cylinder bores
Hope this helps
http://www.acl.com.au/web/aclwebsite.nsf

<font size=-1>[ This Message was edited by: TuFFTECortina on 4/5/02 9:16am ]</font>
 

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I'm actually doing the same thing. ACL have a Hypereutectic for this conversion.

KB also do a Hypereutectic piston for this swap. Part # H3434

I don't have any info on the ACL but KB Engine Parts in Melbourne can fill you in with all the details on the KB
03 9720 6133

Tim
 

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Discussion Starter #6
Thanks for the great info guys I am really disappointed with the minimal gains in HP tho It seems the real advantage is timing is perhaps a little less critical and pehaps a few more revs. Why is it such a popular change given that it is going to be quite a bit more expensive
 

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another thing to consider is your cylinder heads. Short rods tend to work better with heads that have marginal flow rates. This is due to the short-rod engine's piston speed--at top and bottom dead center, the piston changes direction quicker, thus initiating flow faster.
 
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