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Sup? Yeah, I'm planning on changing the spark plugs and wires, what brands do you suggest? I have AC delco and NGK on my mind for the plugs don't know about the wires..any thoughts?
Also, what is the gap for the spark plugs?
 

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Sup? Yeah, I'm planning on changing the spark plugs and wires, what brands do you suggest? I have AC delco and NGK on my mind for the plugs don't know about the wires..any thoughts?
Also, what is the gap for the spark plugs?
I would use ac delco irridium plugs and these are gaped at the factory. you must be very careful not to damage the plug tip if you check the gap. if the gap is not correct get another plug.

the ac delco wires have a resistance of 1500 ohms to 600 ohms. If you use other wires make sure the resistance is in this low range. also 7 MM is the wire diameter so these will fit into the plug wire holders. using wires of a larger diameter you will need new holders to secure these wires.

the metal over the plug boots on some wires [heat shield ] need be reinstalled.
 

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There are many discussions/threads on the Forum on both topics. If you search around you will find lots of info. Most will recommend AC Delco Double Plats for the LT1/L99 but there are other options out there. I used the DP's myself.

As for wires, again a few options there. Due to the PITA it is to change these, especially on the Passenger side, DO NOT skimp on wires and get a quality set. Whether you decide on a stock replacement or something aftermarket....get good wires. Many like myself have used MSD wires. They also make some nice Wire separators that work well with the stock brackets. Although, you can fit the larger wire in the stock 7mm clips. The fit can just be really tight and I found that the stock clips often break due to their age.

Here is how I ran mine when I replaced them recently.

http://www.impalassforum.com/vBulletin/showthread.php?t=271808

Maybe this will give you some ideas on how best to replace the wires. There are also other threads/links out there that walk you through wire replacement using other methods to fish the wires through the bracket. If you think it will take you 2 hours to do, figure it will really take 4 hours to do. :eek: It is not a fun job on our cars but is doable with patience.

Also be sure to seal the plug wire ends with some dieletric grease. Don't remember the Gap (.050?) but most parts places will tell you the recommended Gap on the plugs. The emissions label will also have it on the fan shroud/rad support or in the Service/Chilton's manual. HTH
 

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Thanks for the help everyone, much appreciated. Though, i'm seeing a lot of MSD wires on these cars, also on LSX's. What is the advantage of MSD's over AC Delco's? just for clarification.
 

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AC Delco double plat plugs.

Magnecore wires.
 

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Thanks for the help everyone, much appreciated. Though, i'm seeing a lot of MSD wires on these cars, also on LSX's. What is the advantage of MSD's over AC Delco's? just for clarification.
The MSD wires have a much lower internal resistance than the stock wires (50 ohms per foot vs 1000 ohms per foot) which increases the voltage to the plugs for a hotter spark which improves combustion and efficiency. They also have a thicker jacket (8.5mm vs 7.0mm) which prevents voltage leaks and protects better against high temperatures.

Steve
 

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^^^^^^. This is why I prefer an Performance brand wire over stock. A few brands out there to choose from too. Taylor is also a choice with good reviews
 

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Thanks for the help everyone, much appreciated. Though, i'm seeing a lot of MSD wires on these cars, also on LSX's. What is the advantage of MSD's over AC Delco's? just for clarification.
I just purchased the ac delco wires to replace the ac delco 1995 OEM wires. I found two wires on the driver side to be about 1700 ohms . this is 300 ohms over the new wires. the insulation has no cracks or defects. they fit exactly as the OEM factory built.

the other reason is the wires have a lifetime warranty . so when I check them in 2 years if readings are changing I will get new free replacements.

my guess is that I had no issues over 18 years because when I got this vehicle new I placed dielectric grease in the boot ends . this protects the connections from damage/arcing . I also placed a light coating over the wire length.
 

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AC Delco double plat plugs.

Magnecore wires.
Gotta stir the pot Criss. The pucks on the plats can come off and ping around the cylinder. Had one do this, so I switched to Iridium. Same deal, longevity. Put some iridium's in...A Ford product I think ;)...and they work very well. So plus 2 on the autolite iridium's. Wires? Never had an issue w/ the Taylor's, but that's just another seasoned opine fwiw :D
 

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Gotta stir the pot Criss. The pucks on the plats can come off and ping around the cylinder. Had one do this, so I switched to Iridium. Same deal, longevity. Put some iridium's in...A Ford product I think ;)...and they work very well. So plus 2 on the autolite iridium's. Wires? Never had an issue w/ the Taylor's, but that's just another seasoned opine fwiw :D
I had problems with the plats . wire fell off on 2 plugs , gap then too wide. 40,000miles on them when found. this was on other type vehicle with the aluminum heads. the irridiums can take more heat than the plats. they should last longer .
 
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