Paul,
Very interesting. Keep posting ;)
I'm a little confused by "...keep a 10 to 1compression ratio ..."
I believe the stock CR is 9.1:1.
The "trick" he mentioned is to keep the head stock as a kind of rev-limiter?
bs
PG wrote:
>To follow up on my previous email, here an email I received today from a
>fellow in Arizona that I have been working with to benchflow and design the
>engine.
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>
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>Again, I thought it might be interesting to many of you.
>
>
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>I am relatively new to the list, so if this is taboo, please let me know.
>
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>Paul
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>
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> _____
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>Assuming you went from a stock bore to 88.9 mm bore and keep a 10 to 1
>compression ratio, ran a muffler, used the DW 278 cam, and both heads flowed
>the same. You would get
>
>
>
>Stock 2.9 liter
>
>171 ftlbs at 4952 RPM
>
>179 Hp at 5899 RPM
>
>
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>3.311 liter
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>195 ftlbs at 4107 RPM
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>179 Hp at 5184 RPM
>
>
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>Torque is larglely driven by displacement and compression ratio. Horsepower
>is primary driven by cylinder head flow. In real life the 3.3 liter would
>make 4.2 more horsepower because there is less friction at lower RPM.
>
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>If the head and manifold flow real strong we may need this trick to keep the
>engine RPM below the critical 6000 RPM point.
>
>
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>Note I would leave at least one overbore left. Its a real bummer when you
>have an engine you like that needs to be rebuilt and you have to either
>resleeve the block or buy a new one.
>
>
>
>Cheers Jim
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