Rapid Fire # 5 for me.
spark plugs
Thread Starter
Advanced
Joined: Nov 2006
Posts: 51
Likes: 0
From: Grimsby Ontario
spark plugs
hey guys,
I bought a 90 vert and was doing my own minor tune up. The first mistake I think I made was using NGK plugs. When I purchased them i noticed that they were shorter than the delco's I took out. What plug should i be using? the car does not seem to be running right. I don't want to have to change these things again.
I bought a 90 vert and was doing my own minor tune up. The first mistake I think I made was using NGK plugs. When I purchased them i noticed that they were shorter than the delco's I took out. What plug should i be using? the car does not seem to be running right. I don't want to have to change these things again.
Drifting
Joined: Sep 2003
Posts: 1,363
Likes: 7
From: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
Recently installed NGK TR55ix (iridium), gapped at .050 - .051 OEM gap in our 94 LT1 engine and they seem good so far.
However, they did appear the same size/length as OEM AC/Delco's.
Be careful of assumptions -- are you sure the plugs in the car were the correct plugs?
Note: your engine is different than ours (L98).
Which NGK's did you install? What Gap? Did you torque them carefully using a torque-wrench to spec torque (probably 11-15 ft/lb)?
However, they did appear the same size/length as OEM AC/Delco's.
Be careful of assumptions -- are you sure the plugs in the car were the correct plugs?
Note: your engine is different than ours (L98).
Which NGK's did you install? What Gap? Did you torque them carefully using a torque-wrench to spec torque (probably 11-15 ft/lb)?
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
The NGK plugs are good plugs. Just make sure you got the right numbers and gap them at .035. The TR-55 are for the LT1 engines. Search on the internet at napa and see if you got the right numbers. Other than the NGK plugs I would get the stock AC Delco's. A spark is a spark. The cheapest spark plug you can find will work just as good as any of the others. The only down side to a cheap plug is how long it last. If you change plugs as regularly as I do (every few years), you shouldn't have a problem.
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Thread Starter
Advanced
Joined: Nov 2006
Posts: 51
Likes: 0
From: Grimsby Ontario
hey guys, just looked at the plugs that part source sold me. They are NGK V-Grove. I think they are the wrong plug. the lenght is completly different. the threads are only about 1/2 inch in lenght.
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Well depends on the year you have. '84-'86 with iron heads use a shorter plug, '87-'91 use a longer plug and I have no idea what the LT1 uses.
I use Bosch Platinum by the way. AC Delco is good, never used NGK before but many people like it. Dont use Autolite plugs though they suck. I had to put them in mine and 3 months later a couple are fouled already.
I use Bosch Platinum by the way. AC Delco is good, never used NGK before but many people like it. Dont use Autolite plugs though they suck. I had to put them in mine and 3 months later a couple are fouled already.
No problems with them in my LT1. 
Racer
Joined: Dec 2006
Posts: 369
Likes: 0
From: Indiana
hey guys,
I bought a 90 vert and was doing my own minor tune up. The first mistake I think I made was using NGK plugs. When I purchased them i noticed that they were shorter than the delco's I took out. What plug should i be using? the car does not seem to be running right. I don't want to have to change these things again.
I bought a 90 vert and was doing my own minor tune up. The first mistake I think I made was using NGK plugs. When I purchased them i noticed that they were shorter than the delco's I took out. What plug should i be using? the car does not seem to be running right. I don't want to have to change these things again.
