Fuel injection plugs

Greg Hermann bearbvd at sni.net
Sun May 2 05:46:43 GMT 1999


>Greg:
>    More power to you if you can accomplish that...... I happen to
>live in the real world, and deal with old fashioned Ford & GM engines
>such as the FE series and the Small block & big block GM engines.  The
>comment on life expectancy is based on 20+ years of working on these
>engines.
>    I'd love to see a gas engine with a 500K life in a farm truck, and
>a bcsf below .35............. With the technology people are using
>around here the service life I spoke of is realistic based on real
>life experience, not labratory environments..... some go over 100K
>TBO, but not many, and it is a struggle to achieve a bcsf of .50
>(impossible with a Holley carb).  I've worked on a lot of engines over
>the years, but apparently not seen the bearing setup you
>describe...... I presume you are refering to Ford 239 engine when
>speaking of "flattys", and assume you speak of a single bearing
>spanning an entire rod journal (2 rods)..... I've owned vehicles with
>these engines, but never had to work on them.
>    I'll believe the .35 and 500k figure when I see it in real life!
>
The 500K figure takes a good engine to begin with, and then some high tech
tricks and quality parts on top of that. The engine I have started out with
has a lengthy track record of running 10K hours on the heads, and 25 K
hours on the bottom end, on natural gas, at about 80% load, 2400 rpm on
well head irrigation pump applications.  And that--with "farmer"
maintenance! So--I think, with some careful attention to details, my
durability goal is attainable.

As for the GM motors--going for durability is a bad joke. (With the
exception of the GMC  (247/270/305) I- 6, V-6's and V-12's!) The FE and 385
Fords are considerably better than the usual GM's, and a 534 is better
still, although a (top oiler) FE needs a lot of hand work on the oil
passages in the block in order to live a long happy life. RB Mopars do a
LOT better in the durability dept. than either. Too bad Mopar never built a
REALLY big block motor!!

As to the bsfc--check out some dyno charts for small block f & c engines
running IR manifolded Weber carbs. .375 bsfc is common on these engines
with this type of an induction setup and good headers--given a competent
tuner. In fact--these numbers could just lead a guy to believe that there
is something to this business of wanting better fuel atomization and a fuel
squirt timed to coincide with high inhale velocity in the port!  So--with
good efi, .35 should be within reach for light loads. The real challenge
will be in seeing how much lower than that can be had!! A competently tuned
Holley will get down to about .45 bsfc on a decent motor, in my experience.
(Somewhat lower if not into the power valve, and maybe just a little higher
at WOT if you know how to set the pvcr correctly.)

Regards, Greg





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