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7730 $8D Cylinder Volume

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Old 08-11-2014, 07:52 PM
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7730 $8D Cylinder Volume

Hi Guys,

I am getting up to speed on the 7730 SD system. To date, all of my programming has been on the 7165 $32B mask.

Question on the 7730 $8D Cylinder volume parameter.

The Hacks that I have read set the 5.7L cylinder volume to 0.7125 L or 712.5 cc.

By my calculations, a 350 CID engine is actually 349.848 cubic inches. This translates to 5732.98 cc or 5.73298 L.

Assuming my calculations are correct, why would GM set the Cylinder volume in the BIN lower than the actual value?

Best Regards,

Bruce
Old 08-11-2014, 08:03 PM
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Re: 7730 $8D Cylinder Volume

Volume of one cylinder.

RBob.
Old 08-11-2014, 08:18 PM
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Re: 7730 $8D Cylinder Volume

Thanks RBob,

A 5.73298 L (actual 350 CID) engine has a cylinder volume of 0.71662 L. The Hack cylinder volume is set to 0.7125 L.

Seems like many on this board set the ECM input parameters as close to reality as possible.

Just wondering why GM would not input a more accurate data point?

Maybe an exact volume is not critical?

Best Regards,

Bruce
Old 08-12-2014, 07:20 AM
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Re: 7730 $8D Cylinder Volume

Not sure why GM used that value, but the BIN value is 159 versus 160 for the true cylinder size. Maybe the stroke isn't quite 3.48"? I don't know.

RBob.
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