440 Rebuild

[William Parker <parkerw@xxxxxxxxxxxxxxxxxxxxxx>]

dan.donna.m@xxxxxxx wrote:
> 
> Hi all....this question is for those IML'ers who have rebuilt their motors or
> know of someone who has. First, is it cheaper to just have someone
> professional do the job for you (not withstanding the satisfaction you get
> from saying"I did it myself") or to rebuild the motor yourself? 

     The machine shop I use has flat prices for the various
machining/reconditioning operation on parts, then charges an
hourly rate for assembling the engine, so it wouldn't be
cheaper than doing it myself.  However, if you are only
going to assemble the one engine and need to buy tools to do
so, and wouldn't be using them again, you might be spending
just as much.   


Second, if
> doing the rebuild or having it done is it better to just have it done
> to 'factory specs' or to have it rebuilt the best way present technology
> (within a price range) will allow, meaning maybe upgrading the cam, pistons,
> etc. to get more HP/Torque out of the rebuilt engine??

     I think it depends on your desired result and what you
are starting with.  There's been a trend for a while by the
manufacturers to return to closed chamber heads and running
higher compression, using the "squish" between the top of
the piston and the flat part of the head to improve burning
and stave off detonation.  I was reading about the new motor
for the "2005" Mustang in Hot Rod magazine this morning, it
makes over 300 HP from 281 cubic inches, with I believe it
was 10.5:1 static compression, with recommended 87 octane
fuel, not even 93 octane.  I think the more precise mixture
management of electronic fuel injection also helps them be
able to do this.  
> 
> Just curious what experiences some of you may have had out there and what (if
> any!) lessons were learned!
> Thanks all!!!
> Dan Melnik

     I've found that having static compression ratio in the
10.5:1 range with a somewhat warmer than stock cam makes for
a sharp throttle response and quick revving engine without
detonation, and try to build with that in mind.  I'm not
sure if I would do so for my Imperial though, as I need the
low end grunt to get underway smartly.  I think one
principle is, the hotter the cam, the more static
compression ratio the engine can tolerate without
detonation. For a heavy car with a highway rear ratio and a
tight stock torque converter, the cam needs to be mild, and
with a mild cam, I'd say the static compression ratio needs
to be no more than 10:1 to use regular gas.  I'm not an
engineer or a pro engine builder, this is just what I've
been reading combined with some experience.


-- 
Bill Parker, South Central Indiana
'60 Chrysler Saratoga; '62 Plymouth Max Wedge; '64 Dart
Convertible (Kathi's car); '65 Imperial; '65 Barracuda \6
(Kathi's other car);'68 Barracuda Fastback 340-S; '69
Barracuda Fastback now 360 (22 y.o. son's car); '72 Cuda 340