Modified Bosch Platinum
+ 4 Spark plugs
+ 4 Spark plugs
Ron Rietfors was kind enough to send me
a set of the Bosch platinum + 4 # 4477 to
test and write about. He used a lathe to
remove all but 3/8" of tread . I purchase a
set of civillian Sparkplug adapters NOS
from Jeff at Frontline Surplus but they
are avialable from various vendors and
are very nicely cast pieces of insustrial
art! My many year old stock plugs looked
good when I took then out (no oil on em)
but I did find out that #4 was loose and
had be letting some compression past!
You don't find stuff like this until you
look and the Mutt had been running pretty
good,
I installed a set of NOS Spark Plug wires
at the same time , and off I went for
another test drive.......
a set of the Bosch platinum + 4 # 4477 to
test and write about. He used a lathe to
remove all but 3/8" of tread . I purchase a
set of civillian Sparkplug adapters NOS
from Jeff at Frontline Surplus but they
are avialable from various vendors and
are very nicely cast pieces of insustrial
art! My many year old stock plugs looked
good when I took then out (no oil on em)
but I did find out that #4 was loose and
had be letting some compression past!
You don't find stuff like this until you
look and the Mutt had been running pretty
good,
I installed a set of NOS Spark Plug wires
at the same time , and off I went for
another test drive.......
The Mutt Fired right up , no choke, and had a very sure and smooth slow idle.We headed for the
steep hill for a climb, with the added firepower of the bosch plugs the Mutt climbed the same hill
as before in 3rd gear at 25 mph and little pedal , I gave it a little gas and it took of accelerating to
30mph on the very steep part of the hill and wanted to go even faster , but at that point we were at
the top. The engine felt even more sure of itself , very quick and smooth acceleration at all
RPMs,again more additional power at higher rpms but a noticable increase in the low end as well
and was quieter, which was something I didn't expect, I pulled into the alley and gave it a little
gas, eased the clutch out in third gear and the mutt went on the down the alley lugging but picking
up speed! that something it never could do before.
The addition of the Bosch plugs didn't have as dramatic affect as the K& N air filter but sure
added to the peformance with the two combined, The Mutt engine seems much more harmonic
and balanced at all RPMs ,but I guess thats what good spark and good air flow will do.
Neither of these Mods. take anything way from the Military originality of the Mutt and unless you
look really closely don't even show. They might not be for the folks that restore for shows but for
those of us who use our M151's often for pleasure driving and off road fun they can make a
significant improvement in power and performance. Both the Air filter and the Spark plugs are not
expensive nor do they take much time to do but I am sure glad I did them, Its making the Mutt
even more of a pleasure to drive!!
Thanks to Ron Rietfors for taking the time to do all the R&D to come up with these simple
effective Modifications to get the most out of the M151 engine.
Next I'll be installing Ron's ported and polished Head and Header combo to get the ultimate in
Mutt performance
otter
steep hill for a climb, with the added firepower of the bosch plugs the Mutt climbed the same hill
as before in 3rd gear at 25 mph and little pedal , I gave it a little gas and it took of accelerating to
30mph on the very steep part of the hill and wanted to go even faster , but at that point we were at
the top. The engine felt even more sure of itself , very quick and smooth acceleration at all
RPMs,again more additional power at higher rpms but a noticable increase in the low end as well
and was quieter, which was something I didn't expect, I pulled into the alley and gave it a little
gas, eased the clutch out in third gear and the mutt went on the down the alley lugging but picking
up speed! that something it never could do before.
The addition of the Bosch plugs didn't have as dramatic affect as the K& N air filter but sure
added to the peformance with the two combined, The Mutt engine seems much more harmonic
and balanced at all RPMs ,but I guess thats what good spark and good air flow will do.
Neither of these Mods. take anything way from the Military originality of the Mutt and unless you
look really closely don't even show. They might not be for the folks that restore for shows but for
those of us who use our M151's often for pleasure driving and off road fun they can make a
significant improvement in power and performance. Both the Air filter and the Spark plugs are not
expensive nor do they take much time to do but I am sure glad I did them, Its making the Mutt
even more of a pleasure to drive!!
Thanks to Ron Rietfors for taking the time to do all the R&D to come up with these simple
effective Modifications to get the most out of the M151 engine.
Next I'll be installing Ron's ported and polished Head and Header combo to get the ultimate in
Mutt performance
otter
Part # 4477 or 4478