[DeTomaso] Playboy Pantera for Auction on BaT

[Daniel C Jones]

You want to sonic test on both thrust and non-thrust surfaces (at 0, 90,
180 and 270 degrees around the bore), top, bottom and middle up and down
the block to get an idea of the core shift.  For big power and/or high RPM
applications, I like to see 0.150" on the thrust face.  Milder rebuilds are
fine with 0.120".  You can offset bore cylinders to maximize the thrust
side wall thickness but it's not uncommon to see a single bore or maybe two
with a thin spot needing a sleeve.  351C blocks tend to crack the cylinder
half way up, usually on the thrust side.  A partial fill of hard block (to
the lower water pump bolts) is an option that stabilizes the cylinders
(reduces the column buckling length).  With a properly functioning cooling
system, you can run a partial fill on the street since most of the cooling
happens up top where the combustion occurs.  Note that many modern (and
some old) engines have shallow water jackets for increased strength (and
better NVH).  You may need to add an oil cooler to keep the oil
temperatures in check as they may climb over time, even as the water
temperatures remain within the normal operating range.  The water jackets
and passages need to be clean and the fill should be done prior to any
machining (boring and honing).  You fill one side at a time, positioning
the block deck square with the floor.  Make sure the block is also level
for-and-aft (many engine stands are not).  Before pouring, put the main
caps in place and torque them to spec.  Also, install and torque the other
side head.  Pour the filler then bolt the remaining head in place.  Wait a
day and rotate the block and do the other side.  I'd also wait several
weeks to let the stuff cure before machining.  Final machining should be
done using a torque plate.

> which is why the Australian Blocks are heavier

Based upon my sample (three blocks), the XE Australian blocks are heavier
primarily due to the thicker main webs and unsculpted pan rails.  The
cylinder walls are not Siamese and only slightly thicker than standard
blocks.  However, they all got sonic tested and the ones that passed
inspection went into the race program and the ones that failed were
installed in Australian market passenger vehicles.  On my scale, the
standard Australian blue and black 2 bolt main blocks don't weigh much, if
any, more than similar U.S. blocks.  In addition to the XE blocks, there
were U.S. SK blocks that did have Siamese bores but retained the thinner
main webs and sculpted pan rails of production blocks.  Kaase told me he
did have one block, the only one he ever saw, with both the SK Siamese
bores and XE thicker mains and unsculpted pan rails but it went missing
after a move.

Dan Jones
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   You want to sonic test on both thrust and non-thrust surfaces (at 0,
   90, 180 and 270 degrees around the bore), top, bottom and middle up and
   down the block to get an idea of the core shift.A  For big power and/or
   high RPM applications, I like to see 0.150" on the thrust face.A
   Milder rebuilds are fine with 0.120".A  You can offset bore cylinders
   to maximize the thrust side wall thickness but it's not uncommon to see
   a single bore or maybe two with a thin spot needing a sleeve.A  351C
   blocks tend to crack the cylinder half way up, usually on the thrust
   side.A  A partial fill of hard block (to the lower water pump bolts) is
   an option that stabilizes the cylinders (reduces the column buckling
   length).A  With a properly functioning cooling system, you can run a
   partial fill on the street since most of the cooling happens up top
   where the combustion occurs.A  Note that many modern (and some old)
   engines have shallow water jackets for increased strength (and better
   NVH).A  You may need to add an oil cooler to keep the oil temperatures
   in check as they may climb over time, even as the water temperatures
   remain within the normal operating range.A  The water jackets and
   passages need to be clean and the fill should be done prior to any
   machining (boring and honing).A  You fill one side at a time,
   positioning the block deck square with the floor.A  Make sure the block
   is also level for-and-aft (many engine stands are not).A  Before
   pouring, put the main caps in place and torque them to spec.A  Also,
   install and torque the other side head.A  Pour the filler then bolt the
   remaining head in place.A  Wait a day and rotate the block and do the
   other side.A  I'd also wait several weeks to let the stuff cure before
   machining.A  Final machining should be done using a torque plate.
   > which is why the Australian Blocks are heavier
   Based upon my sample (three blocks), the XE Australian blocks are
   heavier primarily due to the thicker main webs and unsculpted pan
   rails.A  The cylinder walls are not Siamese and only slightly thicker
   than standard blocks.A  However, they all got sonic tested and the ones
   that passed inspection went into the race program and the ones that
   failed were installed in Australian market passenger vehicles.A  On my
   scale, the standard Australian blue and black 2 bolt main blocks don't
   weigh much, if any, more than similar U.S. blocks.A  In addition to the
   XE blocks, there were U.S. SK blocks that did have Siamese bores but
   retained the thinner main webs and sculpted pan rails of production
   blocks.A  Kaase told me he did have one block, the only one he ever
   saw, with both the SK Siamese bores and XE thicker mains and unsculpted
   pan rails but it went missing after a move.
   Dan Jones