Autolite XP Iridium XP5325 Review Spark Plugs

RupertPupkin · 12-03-2011, 02:24 PM

I received a free set of plugs for review from Autolite. I followed the typical DIY to remove the cowl and engine cover.

I used a socket set, 5/8 spark plug socket, screwdriver

The car is my 2006 330i 6MT with 73xxx miles on the odometer and stock original NGK plugs.

I will post a review after some miles of driving but upon initial startup and idle everything seemed smooth and no CEL or anything. They seem well built and are a pretty typical spark plug.

The OEM plugs weren't really that bad as you'll see, but fresh plugs can't hurt. The OEM plugs all showed some rust coloring around the ceramic.

One observation was that the Autolite plugs are shorter into the cylinder than the NGK. Second to last photo shows them held together with the washers at the same position, you can see that the ignition spot is clearly not as far into the cylinder. Not sure if this matters or not but it turned on fine and drives fine. Enjoy.

RupertPupkin · 12-03-2011, 02:30 PM

Drove about 40 miles tonight. Car is smooth. I didn't really expect anything out of changing plugs. If anything at all and this might be placebo effect, it seems the throttle is a tiny bit more responsive. Otherwise well built and no issues whatsoever.

Glim · 12-04-2011, 03:49 AM

Do the autolites have an antisieze coating like NGK or did you use some copper antisieze?

RupertPupkin · 12-04-2011, 09:38 AM

Quote:

Originally Posted by Glim

Do the autolites have an antisieze coating like NGK or did you use some copper antisieze?

I believe the literature somewhere said the threads are nickle plated, and had some sort of oily substance on them. Not sure if it was anti seize or not. I personally have never used anti seize on spark plugs before and have never had any problems. On my past car went 100k miles and took them right out. I typically change plugs every 50 or so. TO me its a cheap way to ensure full ignition but maybe im weird.

bimmercub · 12-31-2011, 12:45 AM

I just installed on mine too. They seems fine and no idling issues.

33beto · 12-31-2011, 04:32 PM

those XP look like 2 heat ranges colder. (less detonation in hot weather)

RupertPupkin · 12-31-2011, 04:43 PM

Quote:

Originally Posted by 33beto

those XP look like 2 heat ranges colder. (less detonation in hot weather)

How can you tell?

33beto · 12-31-2011, 05:52 PM

NGK website has all the details about heat ranges

RupertPupkin · 12-31-2011, 07:12 PM

Quote:

Originally Posted by 33beto

NGK website has all the details about heat ranges

Cool thanks. How does that heat range affect it in colder temperatures? Do you think these are not as good as OEM due to the heat range difference?

12-03-2011, 02:24 PM	#1
RupertPupkin Major 101 Rep 1,456 Posts Drives: Freak Beast Join Date: Aug 2011 Location: East iTrader: (5)	Autolite XP Iridium XP5325 Review Spark Plugs I received a free set of plugs for review from Autolite. I followed the typical DIY to remove the cowl and engine cover. I used a socket set, 5/8 spark plug socket, screwdriver The car is my 2006 330i 6MT with 73xxx miles on the odometer and stock original NGK plugs. I will post a review after some miles of driving but upon initial startup and idle everything seemed smooth and no CEL or anything. They seem well built and are a pretty typical spark plug. The OEM plugs weren't really that bad as you'll see, but fresh plugs can't hurt. The OEM plugs all showed some rust coloring around the ceramic. One observation was that the Autolite plugs are shorter into the cylinder than the NGK. Second to last photo shows them held together with the washers at the same position, you can see that the ignition spot is clearly not as far into the cylinder. Not sure if this matters or not but it turned on fine and drives fine. Enjoy. Attached Images
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12-03-2011, 02:30 PM	#2
RupertPupkin Major 101 Rep 1,456 Posts Drives: Freak Beast Join Date: Aug 2011 Location: East iTrader: (5)	Reserved Drove about 40 miles tonight. Car is smooth. I didn't really expect anything out of changing plugs. If anything at all and this might be placebo effect, it seems the throttle is a tiny bit more responsive. Otherwise well built and no issues whatsoever. Last edited by RupertPupkin; 12-03-2011 at 10:25 PM..
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12-04-2011, 03:49 AM	#3
Glim Captain 23 Rep 780 Posts Drives: 2006 330i & 2013 X5 35i Join Date: Jun 2011 Location: Victoria, BC iTrader: (0)	Do the autolites have an antisieze coating like NGK or did you use some copper antisieze?
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12-31-2011, 12:45 AM	#5
bimmercub Private 1 Rep 79 Posts Drives: 325I Join Date: Jul 2011 Location: San Francisco iTrader: (1)	I just installed on mine too. They seems fine and no idling issues. __________________ Between two evils, I always pick the one I never tried before
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12-31-2011, 04:32 PM	#6
33beto Second Lieutenant 15 Rep 275 Posts Drives: R.I.P. 08 E90 328i/GM 6L45E Join Date: May 2011 Location: New Jersey iTrader: (0)	those XP look like 2 heat ranges colder. (less detonation in hot weather) __________________ R.I.P 10/14/12
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12-31-2011, 05:52 PM	#8
33beto Second Lieutenant 15 Rep 275 Posts Drives: R.I.P. 08 E90 328i/GM 6L45E Join Date: May 2011 Location: New Jersey iTrader: (0)	NGK website has all the details about heat ranges __________________ R.I.P 10/14/12
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