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Original Message
The compression will be too high.
By Dave Shoe - 07/07/2002 12:45:39 PM; IP 63.233.226.154
If you keep those heads, you'll be able to use the truck's stock exhaust system (bolts right up), and naturally you'll be forced to use the FT intake manifold with those heads.

Still, I see the compression sitting around 10.0:1 (not calculated - just guessing based on info fragments) which is too high for a big truck, regular gasoline, or a mild camshaft. Note that the irigation service manual falls flat on it's face when describing the compression ratio of the motor, as it simply lists 428PI specs verbatim. This is not correct.

Mild camshafts offer the highest static compressions because the intake valve closes so early. This makes detonation an issue.

I believe the propane fuel is tougher to detonate and also offers less energy than gasoline, so the 428 irrigation motor was able to use the higher compression without problems.

You might try installing a 390 crankshaft in the block to create a low-compression 406. Note that all iron cranks are made of nodular iron. The 390 crank is stronger and stiffer than any 428 crank and would allow using cheap cast 428CJ pistons. I have not done the math, but suspect you cound get truck-like "performance" compressions outta this combo.

Note that the 390 pickup truck uses 410 car pistons to achieve it's reduced compression. The 360 pickup uses 390-4V car pistons to achieve it's reduced compression, too. Note that these compressions are still about a point higher than the 330/361/391 FT engines.

Shoe.
This thread, so far...
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Collapse <a href=../ForumFE/reply.aspx?ID=13503&Reply=13503><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor13503" onclick="return false;">C7TE-C heads</a>&nbsp;-- <font color=#0000ff>Troy, <i>07/02/2002</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=13503', contentMargin: 60, icon: $('anchor13503') }); </script>  C7TE-C heads -- Troy, 07/02/2002
Collapse <a href=../ForumFE/reply.aspx?ID=13536&Reply=13503><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor13536" onclick="return false;">they are standard FT heads.</a>&nbsp;-- <font color=#0000ff>Dave Shoe, <i>07/05/2002</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=13536', contentMargin: 60, icon: $('anchor13536') }); </script>  they are standard FT heads. -- Dave Shoe, 07/05/2002
Collapse <a href=../ForumFE/reply.aspx?ID=13537&Reply=13503><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor13537" onclick="return false;">Thanks Shoe, I've got a couple of quick ?'s left..</a>&nbsp;-- <font color=#0000ff>Troy, <i>07/06/2002</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=13537', contentMargin: 60, icon: $('anchor13537') }); </script>  Thanks Shoe, I've got a couple of quick ?'s left.. -- Troy, 07/06/2002
Collapse <a href=../ForumFE/reply.aspx?ID=13538&Reply=13503><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor13538" onclick="return false;">Dump the heads.</a>&nbsp;-- <font color=#0000ff>Dave Shoe, <i>07/06/2002</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=13538', contentMargin: 60, icon: $('anchor13538') }); </script>  Dump the heads. -- Dave Shoe, 07/06/2002
Collapse <a href=../ForumFE/reply.aspx?ID=13539&Reply=13503><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor13539" onclick="return false;">This is going to be a low rpm motor.</a>&nbsp;-- <font color=#0000ff>Troy, <i>07/06/2002</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=13539', contentMargin: 60, icon: $('anchor13539') }); </script>  This is going to be a low rpm motor. -- Troy, 07/06/2002
Collapse <b>The compression will be too high.</b>&nbsp;-- <font color=#0000ff>Dave Shoe, <i>07/07/2002</i></font>The compression will be too high. -- Dave Shoe, 07/07/2002
Collapse <a href=../ForumFE/reply.aspx?ID=13554&Reply=13503><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor13554" onclick="return false;">Dave, your the best.</a>&nbsp;-- <font color=#0000ff>Troy, <i>07/07/2002</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=13554', contentMargin: 60, icon: $('anchor13554') }); </script>  Dave, your the best. -- Troy, 07/07/2002
 I agree with ya Troy -- P, 07/08/2002
 I believe all FT heads have the same cc volume. -- Dave Shoe, 07/08/2002
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