• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Best replacement spark plugs? Any opinions?

BlackGTP01

BlackGTP01

New member
I'm going to replace my spark plugs and I was curious if there has been any discussion on the Best for these cars?
I tried searching and couldn't find anything.
The car already has MSD wires on it too.
Thanks for any input
 


if your stock get iridium plugs. or copper core plugs in the stock heat range.

iridium will last 75,000 miles or more. copper 12 to 15,000. copper are much cheaper, but dont last as long.
 
The best plugs are the factory plugs. Ac Delco iridium's are A+ and many people go 200k miles with zero issues on them. I was going to change mine at 140k but once I got the old ones out they looked so god I put them right back in.... later on I decided to turn it into a racekar so I have different stuff now... same idea though.
 
Not to thread jack but what I read about recommended the NGK TR55IX for the S/C 3.8L

I went ahead and put those in my GTP. Good choice or should I switch?
 
I used NGK TR55s in my N/A and noticed no difference in operation. They are slightly cooler than stock from what I've been told.
 
no boost = stock plugs.

boost + bolt ons = stock plugs

more boost + bolt ons = one heat range colder, copper

more, more boost = two heat ranges colder, copper
 


Indeed maybe with some explanation why.

I see many people (mostly the facebook goobs) telling people with 100% stock car to run 104s or 103s because it reduces KR a lot or something.
 
well they're stupid.

you always run the hottest spark plug with the biggest gap possible.

when you can't keep the spark plug from dissipating heat on the tip fast enough you move to a "colder" plug. if the plug can't dissipate the heat into the head quickly enough it will cause pre-detonation because it'll light the fuel up before the spark even occurs. if that isn't the case you're just wasting money, time, and probably gas mileage.

again, you always run the hottest spark plug with the biggest gap possible with your setup.
 
4) Spark Plugs - Change out those stock spark plugs with new ones to restore any lost power. Brands that most tend to go with are either Copper Core Autolites or NGK Spark Plugs. Get these at your local auto parts store also. They range as follows in order from hottest to coldest plugs...remember...you want the hottest spark possible...so running a super cold plug on a larger pulley to combat knock isn't the best plan...ACD's, AL606's, and AL605's are basically for stock cars or very small bolt ons still running the stock S/C Pulley or modded N/A guys...you want to keep a hot spark. NGKTR55/AL104's for your 3.4" Setup, TR6's are a tad cooler...best used around the 3.25" pulley area, and AL103's...are for the extreme supercharged application...3.0" pulley or lower. Here is a picture to reference the firing order and the correct coil number if yours aren't numbered or you just need a quick reference picture: http://i33.photobucket.com/albums/d6.../plugwires.jpg


AC Delco Factory Replacements: Stock
Autolite 606: Stock
Autolite 605: 1 Heat Range Cooler
NGK TR55: 1 Heat Range Cooler
Autolite 104: 2 Heat Ranges Cooler
NGK TR6: 2 Heat Ranges Cooler
Autolite 103: 3 Heat Rangles Cooler


5) Spark Plug Wires - If you need some new wires, opt for the stock Lifetime Warranty Auto Parts store brand from your local auto parts store, but if you want to upgrade and need new wires now is a great time. Coil Packs, leave the stock ones...don't waste your money on MSD's as they are actually proven to fail within a years time and put out LESS spark than stock units. Companies that offer aftermarket plug wires are MSD Ignition, Taylor Wires, and PRJ Performance. All ranging from 8mm to 10.4mm monster wires. Cost: $60-$120


http://www.grandprixforums.net/threads/17482-Safely-Modding-Your-3800-Powered-Car
 
Bio248 said:
well they're stupid.

you always run the hottest spark plug with the biggest gap possible.

when you can't keep the spark plug from dissipating heat on the tip fast enough you move to a "colder" plug. if the plug can't dissipate the heat into the head quickly enough it will cause pre-detonation because it'll light the fuel up before the spark even occurs. if that isn't the case you're just wasting money, time, and probably gas mileage.

again, you always run the hottest spark plug with the biggest gap possible with your setup.
Click to expand...

yep
 


BlackGTP01 said:
I'm going to replace my spark plugs and I was curious if there has been any discussion on the Best for these cars?
I tried searching and couldn't find anything.
The car already has MSD wires on it too.
Thanks for any input
Click to expand...

Right....


Not picking on you because you are new or anything, but I bet I can find 50 threads on spark plugs.
 
So either run iridium or NGK plugs it seems like.
I have a smaller pulley with intake, headers, and exhaust.
Thanks for all the positive input

Fivefingerdeathpunch said:
Right....


Not picking on you because you are new or anything, but I bet I can find 50 threads on spark plugs.
Click to expand...


Apparently I was lying, the search at the top of the page shows nothing besides the thread I just started.
It's not allowing me to add the screenshot because it's too big. Tried shrinking with no luck. If I found it I wouldn't haven't started a post.
 
Russosaur said:
Iridium is the type of plug, so like a NGK or Autolite Iridium.
Click to expand...


Autolite Iridiums are actually Iridium ENHANCED. I would just get AC Delco Iridium because they are 1. A Great Plug that will last 100k+, 2. Made by NGK, and 3. AC Delco has a rebate on those plugs so if you get 6 plugs, you'll get a $12 rebate
 


BlackGTP01 said:
Apparently I was lying, the search at the top of the page shows nothing besides the thread I just started.
It's not allowing me to add the screenshot because it's too big. Tried shrinking with no luck. If I found it I wouldn't haven't started a post.
Click to expand...


you need to host your pics at photobucket, or the likes and then post the direct link or img link to the 3 rd icon from the right in the reply window.
 
You must log in or register to reply here.
Back
Top