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Discussion Starter #1
I'm a long way from doing any major engine rebuilds to my 2 month old '07 sedan, but I'm curious...

If all that is different in the buildup of the 2.3 and the 2.0 is the length of the rods, is there room in the block for even longer rods i.e. even more displacement?





EDIT: since lots of people with turbos have had internal engine work done, i thought this section was the best place to put this question...
 

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i can grab the info if needed, but the 2.3 already has a rather long stroke, you'd be better off going wider rather than longer. piston speed might prove to be an issue when going longer.

...just my thoughts
 

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Discussion Starter #3
well what might the options be for going wider?
 

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It is not just the stroke. The rods are different (longer in the 2.3) the crank has also larger diameter at the rod end. There are sleeves available from Darton and they might have different and larger diameter. Maybe 1.5 to 2 mm oversize.
 

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Since the 2.0 and the 2.3 share the same block with the same deck height, why would the 2.3 have the longer rod? I would assume that the 2.0 would have the longer rod to make up for the less stoke in the crank. since the 2.3 crank has a larger stroke it would need a shorter rod. Unless the pin postions were different in the pistons, but still couldn't expain the 2.0 have a longer rod. Maybe the same rod just different pin positions on the pistons. My first assumption would be the 2.3 has a shorter rod.
 

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[quote author=rider73873 link=topic=66849.msg1274371#msg1274371 date=1174231573]
Since the 2.0 and the 2.3 share the same block with the same deck height, why would the 2.3 have the longer rod? I would assume that the 2.0 would have the longer rod to make up for the less stoke in the crank. since the 2.3 crank has a larger stroke it would need a shorter rod. Unless the pin postions were different in the pistons, but still couldn't expain the 2.0 have a longer rod. Maybe the same rod just different pin positions on the pistons. My first assumption would be the 2.3 has a shorter rod.
[/quote]

The piston is the same on both engines except for the top where the 2.3 has a deeper dish to lower the compression. The block is taller, the rod is longer and the cranksahft is differentin the 2.3. In fact, I use the 2.3 piston in the 2.0 to lower the compression.
 

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[quote author=HiBoost MZ3 link=topic=66849.msg1274620#msg1274620 date=1174242308]
[quote author=rider73873 link=topic=66849.msg1274371#msg1274371 date=1174231573]
Since the 2.0 and the 2.3 share the same block with the same deck height, why would the 2.3 have the longer rod? I would assume that the 2.0 would have the longer rod to make up for the less stoke in the crank. since the 2.3 crank has a larger stroke it would need a shorter rod. Unless the pin postions were different in the pistons, but still couldn't expain the 2.0 have a longer rod. Maybe the same rod just different pin positions on the pistons. My first assumption would be the 2.3 has a shorter rod.
[/quote]


The piston is the same on both engines except for the top where the 2.3 has a deeper dish to lower the compression. The block is taller, the rod is longer and the cranksahft is differentin the 2.3. In fact, I use the 2.3 piston in the 2.0 to lower the compression.
[/quote]

So if the 2.3 has better rod/stroke ratio, the 2.3 with modded valvetrain will handle better in high rpm than the 2.0??

For what hp application do i have to get the block sleeved?
 

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As far as I know the valvetrain is the same in both engines excpet for the variable intake camshaft in the 2.3.

I make 500+ whp on the stock engine block.
 

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[quote author=HiBoost MZ3 link=topic=66849.msg1456387#msg1456387 date=1180838336]
As far as I know the valvetrain is the same in both engines excpet for the variable intake camshaft in the 2.3.

I make 500+ whp on the stock engine block.
[/quote]

Which one revs higher??
 

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they both rev the same
 

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the shorter stroke of the 2.0 would be better suited for higher rpm than the 2.3 but that is a moot point because as it stands these engines do not make power beyond 6500 rpm. You would have to change the cam profile and intake manifold etc. to get the engine to produce power above that range.
 

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[quote author=hoffo link=topic=66849.msg1459117#msg1459117 date=1180972101]
the shorter stroke of the 2.0 would be better suited for higher rpm than the 2.3 but that is a moot point because as it stands these engines do not make power beyond 6500 rpm. You would have to change the cam profile and intake manifold etc. to get the engine to produce power above that range.
[/quote]

that its not determined only because of the stroke, its also determined by the rod lenght.... short stroke and short rods have poor rpm capabilities...
 

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