I have had my car for almost 3 years. I was told by the last owner that he put the plugs in a year before I bought the car. I am guessing the AC plats have been in there for almost 4 years and I have never changed them. Should I be changing them. I thought about putting the NGK TR55 plugs in since alot of people on here suggest them. How long do you guys leave plat plugs in, and I wires I guess. They havent been changed either.

 

The Delcos are known to last less than 40K before losing their pucks. I'd suggest changing them out so you know what you have. If you go with the NGK TR55s (copper) they are better conductors than the TR55VXs (plats) or the Iradiums, but coppers, supposedly don't last very long and changing the plugs is a real challenge.

The plats and iradiums will last longer, but they also cost about $50 a set, but that isn't much if you don't relish changing the plugs every year or so.

Gap .050 for NA and use anti-seize when installing. Don't over torque them and I'd suggest getting some help from those who have lots of experience changeing them (on this site) so that you don't wind up spending all day on them.

 

i've pulled the factory (or what appeared to be factory) plats out of both my 96 and my 99 right around 50-55K miles.

on BOTH cars, 4 of the 8 plugs had lost the platnum puck.

on BOTH cars i installed NGKs....for $2 each...even if they don't last as long as the plats are "supposed to"...i can still save money by replacing them 2 or 3 times more often.

yeah it's more work on an LT1, but for my LS1 i can do all 8 in an hour or less.

 

AC Delco and GM dealerships will claim that the platinum plugs are good for up to 100,000 miles. It is a big sales pitch. Any knowledgeable mechanic will tell you DO NOT leave them in that long.

The problem is that bi-metal reactions cause the plugs to bind themselves to the aluminum head. I saw way too many GM vehicles come in for plugs and wires at 100,000+... and end up needing expensive head repairs because the plugs stripped or broke, coming out.

Save yourself the aggravation. It's worth the time and money to change them at the traditional 30,000 mile tune-up.

 

Just my personal experience... On only one LT1... I replaced my original Delco plats at around 120K miles. 3 of the 8 had lost their ground electrode "pucks". That being said, I had not notice that the car was running badly and there was not any improvement in performance or gas milage after new plugs, wires, and optispark. As much of a PITA as it is to change the plugs on a LT1, I wouldn't do it again unless the car is running badly and I think the plugs might be the problem... My Z was over 10 years old and had 120K miles on it and was still running well on the original ignition stuff...
I do drive the car year round and the car is never raced...

On my isuzu pickup, I can change the plugs in literally 15 minutes... I change them out every 30k miles with NGK plugs...

 

I'd pass on the Delcos. Several of my pucks came off in under 20k. I just installed NGK iridium plugs on mine.

When I changed wifey's Lexus plugs at 112k miles her iridium tip plugs were still at the oem gap recommendation. I replaced them with the new NGKs I had purchased anyway. Those iridiums sure do last.

 

How much can these old plugs affect the running of my car. I figured them to have about 60,000 miles on them. I will prob replace them with the NGK TR-55 since alot of you guys like them. I have a lift to use so changing plugs wont be as bad for me.

 

You obviously haven't changed plugs in a 4th gen LT1 before. Having a lift is nice but having long arms and fingers the size of Yoda's would serve one better.

I'd bet several of the plug's pucks are gone and the gap is wider than desired. You'd probably pick up some lost power and have a smoother idle with new plugs.

 

Well its my lucky day. I have a lift, I am a long armed, yoda fingered freak. I wish. ha ha ha

 

I replaced the factory plugs/wires on my 96 SS with 85k on them. When I pulled them they looked fine, and the only reason I changed them was due to mileage, nothing else.

 

113,000 miles on my stock plugs, wires, and opti. I need to replace the plugs and probably will on the long 4th of July weekend. Besides plugs I have been religious about maintenance... oil changes, tire rotations, coolant flushes, fuel filters, air filters, rear diff fluid, and transmission services.

 

I changed out my factory plugs at 65K in one of a number of futile attempts to fix my random miss. All 8 still had their platinum pucks and looked like they were new.

 

Wow this couldnt be more divided. At first everyone said to change them and that the delco plats werent worth a crap, then the second half of the posts say they havent changed their plugs and the plats have held up awesome. What is a guy to do???????

 

Somethin else to think about. Factory gap on my 95 is .045, when all 8 of my delcos lost their pucks, they all were now gapped at .065. A .020 increase in gap puts a lot of stress on an already strapped ignition on a high compression small block. If you like platinums, get some without the little pucks. I like delco plugs, just never been a fan of the double platinum design. It's cheap, and you will have little pieces of loose patinum sooner or later.

-Paul

 

Ok well I think I am going to get the plugs and wires and do that anyway. I am thinking I will get the Taylor 8mm wires, and NGK TR-55 plugs. Do you guys see anything wrong with that setup? Would you guys recommend me getting a new coil too while I am at it?