V6 spark plug question... (Page 1/2)
Tony Kania SEP 08, 10:55 AM
I have a GT with a stroked 3.1. Nothing too fancy. Not a race car. I am pulling and changing out plugs this afternoon, and just curious as to what we use? I do know that I have AC Delcos in there, but not what number designation.

I suppose that I should look at the plugs before asking this, but curiosity and conversation...


Gall757 SEP 08, 12:39 PM
I have read many posts that recommend the original equipment: Delco R42TS copper. They work great in my car, but it's curious that all the newer technologies do not work as well in the 2.8, and I would think the added displacement would not make a difference. A sensitive motor I guess.
olejoedad SEP 08, 01:34 PM
The ignition system is set up for copper plugs, use them.
FX SEP 08, 02:45 PM
I have always used Bosch platinum's in all my cars & trucks including my V6 Fiero. they are said to be good for 100k + miles. I have never had to replace them, ever. No problems at all with the Fiero ignition...
Tony Kania SEP 08, 02:54 PM
Thank you.
claude dalpe SEP 09, 11:21 AM
Me I prefer: ACDELCO 1 Professionnel; Rapidfire® because they have a corrosion resistant plated shell.
OR the : ACDELCO 41809 {#88901015} Professionnel; Double Platine because they have a corrosion resistant nickel plated shell.
The 3 spark plugs on firewall side tend to rust after few time that's why I prefer those spark plug plated.
theogre SEP 09, 12:59 PM
Nickle Plated and other base shell types resist corrosion is a must because "water" get in thru deck lid gap etc on Fiero then on plugs and exhaust. Even then check the shells for rust every year at minimum so can replace before shells rot.
Note: Even if you have a "rubber seal" on the deck lid edge... Try not to open when lid is wet and engine is hot. All water gets dumped on exhaust, plugs, etc. that attack them by crash cooling. That can break the exhaust and cause other problems.

HEI and DIS are made to have normal or "Copper" plugs. Platinum plugs are ok and does last longer and most have plated shells as above. If you find copper w/ plated shell is good too.
Note that "Copper" plugs in only copper core to the center tip to "reduce resistance" and maybe heat control at the tip. Is kind of funny because most street engines require resistor plug types.

Double platinum is useless unless you have a DIS engine like 87 and up L4. DIS engine Hate Gimmick plugs and plugs can/will die fast.

You won't "improve" HEI and other systems will them either but waste money at minimum. Bosch +2 and +4 and other iffy plugs from big names are just Gimmicks same as others like SplitFire that got sue by FTC etc and basically out of business now but others are Big Companies that "eat" any lawsuit costs as "Cost of doing business." Example: Osram Sylvania sued for false ads/labeling saying Silverstar is so much better and cost 2+ times the price and often doesn't last more then a year or two. Now Osram selling LED "upgrades" like many others hiding behind "off road use only" knowing 98+% will be used illegally on US EU etc. roads. (Osram has owned Sylvania for over a Decade but you only see Sylvania brand in the US.)

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

BillS SEP 11, 07:16 PM
I use the NGK equivalent to stock - UR5s.
lou_dias SEP 11, 08:09 PM
Ditto on the NGK UR5's...
pmbrunelle SEP 11, 09:03 PM
I have NGK UR6 plugs, since they're supposed to be the same as stock, but a heat range colder, for my souped-up engine build.

I would like if someone had a list of recommended spark plugs as a function of engine horsepower, for the 2.8.