In your opinion what is the best spark plug?

[Cerwin Vega Fan]

Just curious to see what kind of spark plugs everyone is running and see which ones everyone likes.

[Dave Vince]

Plug

Currently running the delco platinum in my 95 Z. Have had the Autolite platinum, the Bosch Platinum 4, and could not tell the difference. Did not test each at the track however.

[Z Ya Later]

A lot of people here swear by the NGK TR55 plug. They're pretty good, esp. the Irridium variant.

[Rhode Island Red]

Gotta go with the NGK 555 as welll. WHen Ihave dynoed in the past with the stock plugs, the graph was more over the place (really wavy) than when I dynoed with the NGK's (nice clean lines and almost no graph noise). The NGK's give a bettter spark overall BUT if you cant stand having bloody stumps for hands from changing spark plugs (PITA in 4th Gen F-bods) go with the stock (stock last 100k vs roughly 50K for the NGK's ) . I prefer the cleaner spark the NGK's

that's my $0.02 worth ($0.03 Canadian )

[Mark B]

Ive always used ACDelco Rapid Fires.

[97LT1Z28]

I keep using Bosch Platinum because they stay clean the longest.

[Christopherrr]

signature.

[Injuneer]

My experience with 2 sets of the stock AC/Delco plugs was poor. The little platinum pucks tend to fall off - a problem noted by many users - and leave you with a huge gap. I would not trust them to last 100K miles.

For nitrous use I've had good results with the NGK TR6, and Autolite 104 and 103's. With the max 300-shot, its a set of very cold Champion race plugs.

[N20LT4Bird]

I use NGK TR6 plugs, but only because they have the heat range I am looking for. I wouldnt waste my money on Platinums or my favorite.....the split fires or patinum +4. How many grounds do you need? Do they really think the spark is gonna split between the multiple grounds? Gonna go the path of least resistance.....

[Z Ya Later]

Gotta go with the NGK 555 as welll. WHen Ihave dynoed in the past with the stock plugs, the graph was more over the place (really wavy) than when I dynoed with the NGK's (nice clean lines and almost no graph noise). The NGK's give a bettter spark overall BUT if you cant stand having bloody stumps for hands from changing spark plugs (PITA in 4th Gen F-bods) go with the stock (stock last 100k vs roughly 50K for the NGK's ) . I prefer the cleaner spark the NGK's

that's my $0.02 worth ($0.03 Canadian )

You can get more than 50k mi. on TR55's if you get the platinum or irridium variants.

[Kevin - Blown 95 TA]

Platinums are a mileage plug, not a performance plug. The iridium plugs are also a good mileage plug and they can stand a lot of heat. Multiple electrodes are a waste of money - the Bosch +4 design dates back from the 30's. The engineers at the Champion R&D department told me thet they think multiple electrodes block the fuel charge. The single electrode works fine. Indy cars & Formula 1 use no electrode (gapless) designs and a lot of other racers use a single electrode. So stick with the standard configuration and dial in the heat range - you may have to switch brands to get it just right - The cross references aren't exact copies from different manufacturers - they all differ slightly in how they obtain the heat range. I spend a lot of time at work testing plugs, so I know a lot of people in the industry. I can tell you that plugs get redesigned with new features and gimicks partly to sell more plugs. What is really important on a plug besides the fit, reach, & heat range is sharp edges on the electrodes. This is what makes the spark jump better.

[Al 96 Ram Air T/A]

Yup...same experience here with the AC Delco Platinums...junk! Been using NGK ever since...

[Joe 1320]

Ive always used ACDelco Rapid Fires.

That's what I use as well.

[LeeS97Z28]

Which AC Delco Rapid Fire Spark Plug?

I mean what number did you use for our cars?
Thanks Lee!