Spark Plug question
Thread Starter
Instructor
Joined: Jun 2009
Posts: 181
Likes: 0
From: Sioux City Iowa
Spark Plug question
Would anyone be able to help me w/ figuring out the spark plug gap for '85 Vette ?....Right now I bought some auto lite plugs and they are all gapped at .045. Will that be fine?..Thanks, jess.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
I believe yours has iron heads, make sure you have the right plugs. The aluminum plugs are longer on the threads and have a metal washer on them.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
I'm gonna replace them again with a different brand as I don't like the look of rusted plugs. I took a few out, and the threads were fine, but I still don't like it.
I was thinking of going with NGK as it gets good reviews.
Le Mans Master
Joined: Mar 2006
Posts: 7,207
Likes: 311
From: Lino Lakes MN
Just wondering why you chose Autolite? I put in AC Delco plugs in my 89, and after a month I was looking around and noticed the base of the plugs had rusted. I was told this was normal because of the material they are made of. Though, the PO gave me the original AC Delco plugs in a box, and they weren't rusted.
I'm gonna replace them again with a different brand as I don't like the look of rusted plugs. I took a few out, and the threads were fine, but I still don't like it.
I was thinking of going with NGK as it gets good reviews.
I'm gonna replace them again with a different brand as I don't like the look of rusted plugs. I took a few out, and the threads were fine, but I still don't like it.
I was thinking of going with NGK as it gets good reviews.
I"ve been told the NGK plugs burn hotter than the Delco's and can cause damage to your pistons. I don't know if this is true or urban legand but, you may want to reconsider this option.
Intermediate
Joined: Apr 2006
Posts: 42
Likes: 0
From: gainesville fl
never had a problem with NGKs at all. run them in my 400 now, turning it 6400 @ the track. ran them in my sportsman headed 350 years ago too. just get the correct heat range for the application and roll. plus they are as short as the "shorty" plugs that are twice the cost! had good luck with them in a nutshell.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
Cruise-In VIII Veteran
I'm running NGK TR-55 Double Platinum in my LT1 with no problems at all. In fact, I'm very happy with them.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
Melting Slicks
Joined: Feb 2005
Posts: 2,057
Likes: 5
From: Bay Shore, NY
The gap in the early 85's were .045 and then they were changed to .035. Check to see if you have a sticker on the driver's side top of the radiator noting the change. I read some TSB about a change in the HEI distributor back in the day.
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
Cruise-In VIII Veteran
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
I was just wanting to make sure there wasn't something wrong with NGK Copper plugs, as everyone here seems to use the platinum. Sometimes companies make good and bad products.
So, I which do you think would be better for an 89, copper champion plugs, or copper NGK plugs? I would have liked to stay with copper AC Delco, but I don't like how they rust up for some reason, even though the original plugs don't rust up. They must have switched to a different manufacture since then, and the metal they use rusts up unlike the plugs from a couple of decades ago.
