[DeTomaso] 2 bolt vs 4 bolt Mains......care to offer an opinion??

[Daniel C Jones]

> There is no advantage to running a 4-bolt 351C block over a 2-bolt other than
> for bragging rights.  They are exactly the same except for the extra 2 bolts.
> In fact, when 351C blocks fail, the mains are still torqued in place and doing
> fine.

For what Scott wants to do, a 2 bolt main block is fine.  For higher RPM use,
4 bolt mains are prefereble as they reduce main cap walk.  There are some
local drag racers here who started running 2 bolt main blocks and at rebuild
time, the caps would fall off the engine.  Obvious signs of cap walk.  They
switch to Besel main caps and fixed the problem.  Now they are making enough
power (and have enough traction) to split hard blocked 351C's.

> 351C cylinder walls are not any thinner than 302, 5.0, or 351W cylinder walls.

Dave McLain has sonic tested a bunch of 351W's and 351C's and sees no
difference in wall thickness.  In practice, he says they are
equivalent in strength.

> 351C cylinders, however, are mostly unsupported.  They benefit greatly from a
> partial block fill.

That's true of 351W blocks as well.

> I'm sure my oil runs a little bit hotter, but not enough to worry about.

In some cases the oil can get hot enough that an oil cooler is needed.
A good synthetic oil can stand it, but some bearings will start to soften
if kept at high enough temperatures, long enough.

Dan Jones