...Fuel injected, ...of course! What, say 88#/hr injectors??
Bob
-----Original Message-----
From: Craig Baltzer <Craig.Baltzer@anjura.com>
To: 'dakota-truck@buffnet.net' <dakota-truck@buffnet.net>
Date: Monday, July 26, 1999 7:49 PM
Subject: DML: RE: 4.7L vs. 5.2L settled!
>Not get this started but...
>
>1) Overhead cam vs. push rod for power/torque depends on the cam profile
and
>nothing else. Use the same cam profile in each, and they will make almost
>exactly the same power (frictional loss accounting for the difference). The
>valves could care less how they are being opened and when and how much the
>valves are opened is all that matters for power.
>
>2) Flexibility is the key with a motor, and ideally the torque curve should
>be flat across the RPM band. No one likes a pushrod motor that weases like
a
>pig at 4000RPM so that you have to constantly shift, just like no one likes
>a OHC motor that has to be wound up to 6000RPM to make any power.
>
>3) The need for valve timing is not constant; more overlap can produce more
>power at higher RPMs but blows for drivability at lower RPMs. OHC motors
>make variable valve timing practical as the cams are "out of the motor". So
>both low end torque and high end power are possible.
>
>4) Power is a function of how much air goes through the motor. There are
>only a limited number of ways of getting more air through a motor:
> - make it bigger (more CID)
> - make it rev higher
> - forced induction
>Rev it higher obviously produces less low end power than make it bigger
>(more air per RPM in the bigger motor). Once again the valve actuation
>method has nothing to do with any of these, other than OHC motors have
lower
>reciprocating mass, so its possible to "rev it higher".
>
>So, whats the answer? A big ass DOHC supercharged and turbocharged motor
>with variable valve timing and NO2 :-)
>
>Craig
>
>-----Original Message-----
>From: SuperNagz@aol.com [mailto:SuperNagz@aol.com]
>Sent: Monday, July 26, 1999 7:05 PM
>To: dakota-truck@buffnet.net
>Subject: DML: 4.7L vs. 5.2L settled!
>
>
>3 words to settle the 4.7L vs. 5.2L debate:
>
>4.6L vs. 5.0L
>
>I hate to bring up Fords.. but, all in all.. a motor is a motor... more
>specificaly.. a pushrod motor is fairly similiar to another pushrod.. and..
>a
>cammer to a cammer (single)
>
>Anyways, Dodge is now doing what Ford did a few years back. (needless to
>say,
>this is WHY I started buying Dodge)
>
>Pushrods will always be superior to cammers when it comes to heavy
>vehicles/trucks, and/or performance machines.
>
>The Ford 4.6 that replaced the 5.0 was only good for two things... fuel
>economy, and part complexity reduction- Ford replaced nearly all their big
>engines with overhead cammers with many interchangable parts)
>Those two things mentioned above are great for the car company... saves
them
>
>money, and makes them look good on the fuel economy.
>
>When it comes to performance... pushrod will just blow away the cammer that
>replaced it. Gobs of lowend power... and we all know that thats all that
>matters. Who cares if an overhead cammer has say 250 hp at 6,000 rpms...
>think about it.. that engines STILL has to rev across that entire
>underpowered rpm band to get to that high peak rpm.
>On the otherhand... the pushrod monster has instant power off the line...
>sure... a pushrod will run out of steam sooner than the cammer.. but who
>cares, by then, you've shifted to the next gear, and your back at your
lower
>
>rpm/monster power range
>
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