Bosch sparkplugs
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Pro
Joined: Feb 2006
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From: Concord NC
Bosch sparkplugs
I know this is probably a stupid quiestion but im curious. Do the Bosch Platinums +4. I was wondering if they add horsepower or are better than the AC Delco plugs. They have 4 bottom pieces and are pregapped? Better performance??? Thanks
Le Mans Master
Joined: Oct 2003
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From: Director of Bands
St. Jude Donor '08
Originally Posted by C4driver99
I know this is probably a stupid quiestion but im curious. Do the Bosch Platinums +4. I was wondering if they add horsepower or are better than the AC Delco plugs. They have 4 bottom pieces and are pregapped? Better performance??? Thanks
Le Mans Master
Joined: Sep 2004
Posts: 6,019
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From: Conroe Texas
Originally Posted by eschoendorff
Before I changed the plugs in my 93, I did a search and found that very few people had anything good to say about the Bosch plugs. I went with AC Delcos.
had a set of bosch's, pulled them out with less than 1k on them. talked to others, they did the same. i went to split fire plats
Race Director
Joined: Jul 2004
Posts: 16,795
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From: Lake Havasu City, AZ
It seems there are mixed opinions....
I am thrilled with the Bosch Platinum +4 in both my Vettes.
Instant start-up, Much smoother idle, no hesitation... than with the stock AC's I replaced.
Add to that the life of platinums and I won't be busting my knuckles again for quite some time.
Rich
I am thrilled with the Bosch Platinum +4 in both my Vettes.
Instant start-up, Much smoother idle, no hesitation... than with the stock AC's I replaced.
Add to that the life of platinums and I won't be busting my knuckles again for quite some time.
Rich
Race Director
Joined: Dec 2002
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Spark plugs cannot increase torque (power).
Unless it's a case of replace old/fouled/improper plugs with new/correct ones, in which case you're just getting back to baseline.
Larry
code5coupe
Unless it's a case of replace old/fouled/improper plugs with new/correct ones, in which case you're just getting back to baseline.
Larry
code5coupe
Le Mans Master
Joined: Feb 2005
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From: The Motor City
Originally Posted by rocco16
Spark plugs cannot increase torque (power).
Unless it's a case of replace old/fouled/improper plugs with new/correct ones, in which case you're just getting back to baseline.
Larrycode5coupe
Unless it's a case of replace old/fouled/improper plugs with new/correct ones, in which case you're just getting back to baseline.
Larrycode5coupe
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From: Sussex,Wi
2023 Corvette of the Year Finalist - Unmodified
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Originally Posted by rws.1
It seems there are mixed opinions....
I am thrilled with the Bosch Platinum +4 in both my Vettes.
Instant start-up, Much smoother idle, no hesitation... than with the stock AC's I replaced.
Add to that the life of platinums and I won't be busting my knuckles again for quite some time.
Rich
I am thrilled with the Bosch Platinum +4 in both my Vettes.
Instant start-up, Much smoother idle, no hesitation... than with the stock AC's I replaced.
Add to that the life of platinums and I won't be busting my knuckles again for quite some time.
Rich
although I only have the +2s.No power increase, just better/longer lasting than normal plugs.
Le Mans Master
Joined: Dec 2002
Posts: 6,715
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From: Santa Teresa New Mexico
Originally Posted by touringmike
although I only have the +2s.No power increase, just better/longer lasting than normal plugs.
With todays HEI ingnition system any plug will do, there are no super plugs.
Burning Brakes
Joined: Nov 2004
Posts: 1,057
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From: Warren Ohio
Originally Posted by rocco16
Spark plugs cannot increase torque (power).
Unless it's a case of replace old/fouled/improper plugs with new/correct ones, in which case you're just getting back to baseline.
Larry
code5coupe
Unless it's a case of replace old/fouled/improper plugs with new/correct ones, in which case you're just getting back to baseline.
Larry
code5coupe
Race Director
Joined: Dec 2002
Posts: 13,348
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by 95PoloVert
Cut-back and indexed single-electrode plugs are worth a few HP, if you're willing to put in the time to do it.
Cut-back plugs do nothing, at least nothing that can be measured.
Until someone can produce multiple, back-to-back dyno runs that show otherwise, I'll stand on that.
Larry
code5coupe
Instructor
Joined: Jan 2005
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From: So. Jersey
Something to ponder. I have talked to a few mechanic's on the subject of spark and fuel. My question was related to the LT1. In regards to fuel I was informed that the motor was designed with regular 89 and 91 octane in mind, the high the octane the less fuel will have a chance to ignite properly causing unburned fuel in the cylinder and poor combustion. Thus inconjucntion with a +4 plug and high octane you will not get full or proper ignition in the cylinder. This I presume is all thought of when the ECM was programed. With this in mind I would imagine that the +4's would be good in a carburated motor. I have the +2's and run mid grade 91 octane with no problems. Does anyone else have info on this?
Burning Brakes
Joined: Nov 2004
Posts: 1,057
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From: Warren Ohio
Originally Posted by rocco16
Cut-back plugs do nothing, at least nothing that can be measured. Until someone can produce multiple, back-to-back dyno runs that show otherwise, I'll stand on that.
Gains from both added together don't generally exceed 1-2% though...which is pretty close to the limits of dyno-resolution.
Someone around here has done a series of back-to-back testing, and picked up a reproducible 1 mph trap speed on cut-back plugs alone on an L98. Myron Cottrell from TPiS claims 5-8 "dyno-proven" hp on LT1s.
If you have a bench-grinder setup, it only takes a few minutes. Downside is reduced plug life.
Cherish your Hopes...
Joined: Feb 2002
Posts: 13,074
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From: West Palm Beach FL
Cruise-In VII Veteran
St. Jude Donor '05-'06-'07
Originally Posted by onedef92
I like the NGK TR-55 Platinums.
I use NGK in the C5 StuzVette...
...I would go with NGK if they are a plug of choice on the C4
Racer
Joined: Feb 2006
Posts: 462
Likes: 0
From: green valley az
Nothing good to say about Them
Not worth the trouble,stay with factory plugs. If your system is right,high volt coil.msd wires,high output module,good connections,brass terminal cap,your getting everything there is to get.....
Racer
Joined: Jan 2006
Posts: 273
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From: Ithaca Michigan
The spark only takes the path of least resistance, so you can have 25 electrode tips in there and the spark will still find the path of least resistance meaning one is all you really need. I know people who build twin turbo and supercharged engines for a living with state of the art facilities who say one electrode is all you need. Sparkplug makers need a gimmik to get certain people to buy there stuff better or not.