Re: 318 fuel economy

From: jon@dakota-truck.net
Date: Sun May 11 2008 - 23:22:31 EDT


Terrible Tom <silvereightynine@aol.com> wrote:
> So I'm wondering what you folks with 318's have seen for fuel economy.
> Is it unrealistic to hope for 19-20 on the highway if I drive granny-style?

   In a lifted 4x4, possibly... I've gotten somewhere around 21-22 on
the highway with my '96 club cab V8. Granted, this is a 2wd with a 5
speed, but on the other hand, I wasn't driving for mileage by any
stretch of the imagination, and once you're on the highway with the TC
locked up, the advantage of the 5 speed would probably dissapear.
This is also a MPI Magnum which I think (?) is sequential as opposed
to batch fire, so that's probably a little bit of an advantage over a
TBI fed Magnum. Assuming a proper tune though, I don't think your
goal is unreasonable. That tune might be a problem though given that
whatever computer you end up using isn't optimized for the engine
you're actually using, and of course there is the locked down Dodge
hardware to prevent fine tuning. At some point, it might be
worthwhile to invest in a Megasquirt, which is very reasonable in cost
as far as EFI goes, but is still not what I would consider
inexpensive. Not that I'm trying to discourage you or anything, but
if you are shooting for mileage, possibly something like a 600cfm carb
with vacuum secondaries could be tuned to beat a locked down system
like the Dodge TBI setup.

   I recently picked up a wideband O2 sensor setup which I plan to use
to try and tweak the best mileage and power out of the Dart and
Barracuda; I haven't had a chance to play with it yet though (or even
take it out of the box). Something like that would be a great tool to
use when you were out here to tune for best economy at cruise, but
unfortunately, unless you can actually modify the fueling parameters
of the TBI computer, the best it could do is to tell you where your
current setup is; what's needed of course is a way to actually fine
tune your A/F ratio.

-- 
                                          -Jon-

.- Jon Steiger -- jon@dakota-truck.net or jon@jonsteiger.com -. | '96 Kolb Firefly, '96 Suzuki Intruder, Miscellaneous Mopars | `-------------------------------- http://www.jonsteiger.com --'



This archive was generated by hypermail 2b29 : Mon Jun 02 2008 - 00:18:53 EDT