Bosch platinum 4+
Thread Starter
Joined: May 2007
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Bosch platinum 4+
Has someone tried bosch platinum 4+ spark plugs on their intrepid? Please let me know how they worked coz i had to remove them after feeling noticeable power loss, poor acceleration and smelly exhaust fumes when using them. I replaced them with the factory recommended plug and i regained the power and lost the smelly exhaust fumes!
Could it be possible that one of those Bosch spark plugs was bad, or is it that those plugs arent just good for intrepids?
Could it be possible that one of those Bosch spark plugs was bad, or is it that those plugs arent just good for intrepids?
Champion
Joined: Aug 2005
Posts: 3,313
Likes: 8
RE: Bosch platinum 4+
I have not tried them on an Intrepid
but here is a cut from the Magnum Sparkplug FAQ
that indicates what I and Consumers Reports found
in tests:
quote
Bosch Platinum Super+4, P/N 4418 (Resistor 3.6 kohms)
This 4 ground electrode plug with a platinum "fine wire" center is presently
being heavily advertised, but is not recommended by Bosch for:
(1) truck,
(2) heavy towing, or
(3) "high performance/racing" applications.
The +4 plug is said to be designed for reduced number of misfires, low
emissions, and is said to be durable enough to last for 100,000 miles.
There is a brief article on this sparkplug design at:
http://web.archive.org/web/199911171...r/tr119832.htm
NGK also makes multi-ground sparkplugs and calls them the 'Multi Power'
design. Here's how NGK describes their good/bad attributes:
"NGK Multi Power Spark Plugs
NGK Multi Power Spark Plugs feature multiple ground electrodes for
extra-long life in a variety of applications. Spark plugs wear out when the
sharp edges of the ground electrode round off. Therefore, multiple ground
electrodes provide additional surfaces for the spark to travel to, extending
the plug's effective life. Multi Power Plugs are not for all applications, as
they can tend to quench the spark, or hamper the ability of the flame to grow
from the initial ignition point. However, the multiple ground electrode
configuration can help alleviate a number of problems, including hard
starting, excessive fouling or misfiring. They are also effective for vehicles
with very high ignition system voltages and/or combustion chamber
temperatures. Remember that Multi Power Spark Plugs, or any other multiple
electrode type spark plug, cannot provide more than one spark at a time. The
primary purpose of the multiple electrode spark plug is to achieve greater
spark plug durability and reliability over the life of the spark plug."
In a 1995 5.9V8 Magnum the Bosch+4 seems to give quick cold starts, and the
smoothest idle of any plug tested - but this plug seems to be prone to
increased pinging, perhaps because its large gap (0.065 inches) and long
projected nose may be equivalent to a slight ignition advance. This is not the
plug to try if you have a Mopar Perf computer already installed or insist on
using 87 octane all the time.
Bosch advertises increased MPG with this +4 plug, but Consumer Reports found no
mpg difference when compared to factory NGK sparkplugs on a Honda in their own test.
1995 Ram
5.9V8 owner on four 300+ mile test runs over same stretches of Interstate 95
from NC to FL found 2% worse mpg with Bosch Super+4 plugs going northbound
compared to going southbound with Bosch FR7DPX gapped at 0.050 inches. It is
possible this was due to the direction of prevailing winds.
To realiably find whether there is a MPG difference with the Bosch +4 sparkplug would require a very careful test like the two vehicle test procedure called the SAE/TMC Type IV where a modified vehicle is followed by an un-modified vehicle on multiple trips.
There is also a version of the +4, part number 4478 with the larger hex size
of older sparkplugs. The heat range of this plug is not known.
http://www.boschusa.com/index.asp?di...rp=1&sgp=1
end quote
but here is a cut from the Magnum Sparkplug FAQ
that indicates what I and Consumers Reports found
in tests:
quote
Bosch Platinum Super+4, P/N 4418 (Resistor 3.6 kohms)
This 4 ground electrode plug with a platinum "fine wire" center is presently
being heavily advertised, but is not recommended by Bosch for:
(1) truck,
(2) heavy towing, or
(3) "high performance/racing" applications.
The +4 plug is said to be designed for reduced number of misfires, low
emissions, and is said to be durable enough to last for 100,000 miles.
There is a brief article on this sparkplug design at:
http://web.archive.org/web/199911171...r/tr119832.htm
NGK also makes multi-ground sparkplugs and calls them the 'Multi Power'
design. Here's how NGK describes their good/bad attributes:
"NGK Multi Power Spark Plugs
NGK Multi Power Spark Plugs feature multiple ground electrodes for
extra-long life in a variety of applications. Spark plugs wear out when the
sharp edges of the ground electrode round off. Therefore, multiple ground
electrodes provide additional surfaces for the spark to travel to, extending
the plug's effective life. Multi Power Plugs are not for all applications, as
they can tend to quench the spark, or hamper the ability of the flame to grow
from the initial ignition point. However, the multiple ground electrode
configuration can help alleviate a number of problems, including hard
starting, excessive fouling or misfiring. They are also effective for vehicles
with very high ignition system voltages and/or combustion chamber
temperatures. Remember that Multi Power Spark Plugs, or any other multiple
electrode type spark plug, cannot provide more than one spark at a time. The
primary purpose of the multiple electrode spark plug is to achieve greater
spark plug durability and reliability over the life of the spark plug."
In a 1995 5.9V8 Magnum the Bosch+4 seems to give quick cold starts, and the
smoothest idle of any plug tested - but this plug seems to be prone to
increased pinging, perhaps because its large gap (0.065 inches) and long
projected nose may be equivalent to a slight ignition advance. This is not the
plug to try if you have a Mopar Perf computer already installed or insist on
using 87 octane all the time.
Bosch advertises increased MPG with this +4 plug, but Consumer Reports found no
mpg difference when compared to factory NGK sparkplugs on a Honda in their own test.
1995 Ram
5.9V8 owner on four 300+ mile test runs over same stretches of Interstate 95
from NC to FL found 2% worse mpg with Bosch Super+4 plugs going northbound
compared to going southbound with Bosch FR7DPX gapped at 0.050 inches. It is
possible this was due to the direction of prevailing winds.
To realiably find whether there is a MPG difference with the Bosch +4 sparkplug would require a very careful test like the two vehicle test procedure called the SAE/TMC Type IV where a modified vehicle is followed by an un-modified vehicle on multiple trips.
There is also a version of the +4, part number 4478 with the larger hex size
of older sparkplugs. The heat range of this plug is not known.
http://www.boschusa.com/index.asp?di...rp=1&sgp=1
end quote
Registered User
Joined: Apr 2007
Posts: 11
Likes: 0
From: Independence, MO
RE: Bosch platinum 4+
Logic would tell you that the extra metal gets in the way of the spark being open to the fuel/air mixture. It's a sales gimmick, nothing new here--JC Whitney was peddling multiple electrode plugs 40 years ago.
Registered User
Joined: Aug 2007
Posts: 1
Likes: 0
RE: Bosch platinum 4+
I recently replaced the original champion plugs in my 02 trep (102k)and the clerk suggested the Bosch +2 platinums.
Other than the expected gain in power attributed to simply having new plugs - I have perceieved no discernable difference from the Champions which I would have bought if they were in stock.
Other than the expected gain in power attributed to simply having new plugs - I have perceieved no discernable difference from the Champions which I would have bought if they were in stock.
