2.5 STI spark plug pics here

Wombat North · 03-07-2004, 06:58 PM

For those of you who don't know here are pics of what our stock STI plug NGK IFLR6B looks like against the commonly used NGK BKR7E1X 1 heat range colder plug used on modded WRX's.

The BKR7E1X for comparison is the same size as the stock wrx plug.

A bit of difference eh! Now where can we get colder STI plugs, me thinks at this time we're hooped. I've called the normal web plug vendors etc.

* Registered users of the site do not see these ads.

2003 sedan · 03-07-2004, 09:05 PM

Yeah the STi plug extends deeper into the cylinder for sure.
You sure don't want the short threaded plug in that cylinder head(I know you don't).
The heat range difference can usualy be seen by the porcelain length.
I was doing a price check with a vendor the other day and the Iridium plugs were about half the price of the Laser platinum.
Just thought I would share.
Dwight

Monsito · 03-07-2004, 10:40 PM

Did you pull that plug from your STi? It does not look like a happy plug. It looks a little glazed. How many miles do you have on your car?

Wombat North · 03-07-2004, 10:41 PM

Quote:

Originally posted by 2003 sedan
Yeah the STi plug extends deeper into the cylinder for sure.
You sure don't want the short threaded plug in that cylinder head(I know you don't).
The heat range difference can usualy be seen by the porcelain length.
I was doing a price check with a vendor the other day and the Iridium plugs were about half the price of the Laser platinum.
Just thought I would share.
Dwight

Thanks
Any vendor you talk with carry colder ones

I posted these pics because just a few posts down is this
http://forums.nasioc.com/forums/show...hreadid=459809

Some are going to be in for a surprise

Kenneth2000 · 03-08-2004, 05:00 PM

Good Info, thanks for posting that ... I'm just ordering a set from the dealer for now .. hopefully, someone will figure out what a heat range colder plug would be for our STi's .....

Like maybe a Denso or something ....

mr2guru · 03-08-2004, 07:00 PM

Wonder why it goes into the bore like that?

Wombat North · 03-08-2004, 07:54 PM

Quote:

Originally posted by mr2guru
Wonder why it goes into the bore like that?

I too would like to know. By the looks of the plug it sticks into the combustion chamber by a few threads?

byroll01 · 03-11-2004, 12:02 PM

I can't believe that anyone changing their plugs wouldn't notice a difference that BIG!

Thanks for the info I was about to drop the cash on the colder plugs. I would've been pissed!

Keep us informed when there is a colder replacement available.

byron

STI30G · 04-20-2007, 02:33 AM

my car keeps misfiring and i cant figure out why? Then i compared my plugs and stock from one step colder is a huge difference? What plugs should i use in my 2004 STI?

mathetes · 04-20-2007, 02:40 AM

holy 3-year-old thread batman..

you can use the ngk bkr7e1x a step colder or bkr6e1x for same heat range

x99percent · 04-20-2007, 11:18 AM

Quote:

Originally Posted by mathetes

holy 3-year-old thread batman..

you can use the ngk bkr7eix a step colder or bkr6eix for same heat range

NO.

Those are plugs for the WRX, and they are too short for the UDSM STi.

As noted in the first post, the stock plugs are NGK ILFR6B (note: 26.5mm reach). One step colder replacements are NGK LFR7AIX (obsolete NGK part, but sparkplugs.com still has some).

Edit: A new part number is NGK ILFR7H ... these should last longer than the LFR7AIX, as they are in the same series as the stock plug (meant to last).

Jitenshakun · 06-18-2008, 10:09 AM

According to NAPA all spark plug numbers are changing and given the scarcity of the new plugs you may want to go with the old ones for now.

NGK one step colder plugs for your STI

LFR7AIX = 2309
ILFR7H = 5245

-J

eb_rat_7 · 10-03-2008, 06:27 PM

does anyone know if the ILFR7H or LFR7AIX will fit an 2006 wrx 2.5L? also, what is the difference between the two?

gtasti · 10-03-2008, 06:43 PM

pics dont work btw

vinceGC8 · 10-03-2008, 08:21 PM

Quote:

Originally Posted by gtasti

pics dont work btw

pics dont work cuz the original post is from over 4 years ago.

03-07-2004, 06:58 PM	#1
Wombat North Scooby Specialist Member#: 21267 Join Date: Jul 2002 Location: Eats, roots and then leaves Vehicle: STI, EWG 8cm Green UTEC/ECUtek/WI & SD tune	2.5 STI spark plug pics here For those of you who don't know here are pics of what our stock STI plug NGK IFLR6B looks like against the commonly used NGK BKR7E1X 1 heat range colder plug used on modded WRX's. The BKR7E1X for comparison is the same size as the stock wrx plug. A bit of difference eh! Now where can we get colder STI plugs, me thinks at this time we're hooped. I've called the normal web plug vendors etc. * Registered users of the site do not see these ads.

03-11-2004, 12:02 PM	#8
byroll01 Scooby Specialist Member#: 611 Join Date: Dec 1999 Chapter/Region: Tri-State Location: Saratoga Springs NY Vehicle: 14 E63s AMG 09 ML63 AMG	I can't believe that anyone changing their plugs wouldn't notice a difference that BIG! Thanks for the info I was about to drop the cash on the colder plugs. I would've been pissed! Keep us informed when there is a colder replacement available. byron Last edited by byroll01; 03-16-2004 at 02:18 AM.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
FS/MN: NGK Iridium Spark Plugs (LFR7AIX) 2.5 STi/WRX - One Step Colder	WRXEcho	Engine/Power/Exhaust	4	09-01-2008 02:42 AM
[B]NGK IRIDIUM Spark Plugs for 2.5 STi - $19 SHIPPED!!![/B]	Mr. Quick	Engine/Power/Exhaust	1	11-28-2007 04:51 PM
STOCK NGK IR Spark Plugs for 2.5 STi - $19 SHIPPED!!!	Mr. Quick	Engine/Power/Exhaust	0	11-28-2007 04:50 PM
NEW! 2.5 SOHC spark plug wires (RED)	Reason01	Engine/Power/Exhaust	3	09-17-2007 03:14 PM
FS: SC 2.5 Impreza Spark Plug Wires NIB	markers	Engine/Power/Exhaust	1	08-07-2007 05:24 PM

03-07-2004, 09:05 PM	#2
2003 sedan Scooby Specialist Member#: 24103 Join Date: Sep 2002 Location: Vegas....BABY!!!!!!	Yeah the STi plug extends deeper into the cylinder for sure. You sure don't want the short threaded plug in that cylinder head(I know you don't). The heat range difference can usualy be seen by the porcelain length. I was doing a price check with a vendor the other day and the Iridium plugs were about half the price of the Laser platinum. Just thought I would share. Dwight

03-07-2004, 10:40 PM	#3
Monsito Scooby Specialist Member#: 40581 Join Date: Jul 2003 Chapter/Region: MWSOC Location: Chicago Vehicle: 04 STi Blue	Did you pull that plug from your STi? It does not look like a happy plug. It looks a little glazed. How many miles do you have on your car?

03-08-2004, 05:00 PM	#5
Kenneth2000 Scooby Newbie Member#: 6375 Join Date: May 2001 Location: Omaha, NE Vehicle: 2004 STi Java Black Pearl	Good Info, thanks for posting that ... I'm just ordering a set from the dealer for now .. hopefully, someone will figure out what a heat range colder plug would be for our STi's ..... Like maybe a Denso or something ....

03-08-2004, 07:00 PM	#6
mr2guru Scooby Specialist Member#: 10334 Join Date: Sep 2001 Location: St. Louis Vehicle: 91 RX7 LSx swap '09 CC 3.6 4motion	Wonder why it goes into the bore like that?

04-20-2007, 02:33 AM	#9
STI30G Scooby Newbie Member#: 143359 Join Date: Mar 2007 Chapter/Region: NWIC Location: Renton Vehicle: 04 STI Blue	my car keeps misfiring and i cant figure out why? Then i compared my plugs and stock from one step colder is a huge difference? What plugs should i use in my 2004 STI?

04-20-2007, 02:40 AM	#10
mathetes Scooby Newbie Member#: 106238 Join Date: Jan 2006 Chapter/Region: BAIC	holy 3-year-old thread batman.. you can use the ngk bkr7e1x a step colder or bkr6e1x for same heat range

06-18-2008, 10:09 AM	#12
Jitenshakun Scooby Specialist Member#: 61586 Join Date: May 2004 Chapter/Region: W. Canada Location: Alberta Vehicle: 2005 STi WI and all the goodies	According to NAPA all spark plug numbers are changing and given the scarcity of the new plugs you may want to go with the old ones for now. NGK one step colder plugs for your STI LFR7AIX = 2309 ILFR7H = 5245 -J

10-03-2008, 06:27 PM	#13
eb_rat_7 Scooby Specialist Member#: 106910 Join Date: Feb 2006 Chapter/Region: NESIC Location: MA Vehicle: 2016 GTI C6 ZO6 track toy	does anyone know if the ILFR7H or LFR7AIX will fit an 2006 wrx 2.5L? also, what is the difference between the two?

10-03-2008, 06:43 PM	#14
gtasti Scooby Specialist Member#: 152036 Join Date: Jun 2007 Chapter/Region: E. Canada Location: Ontario Vehicle: 2005 Sti Wrb rhd	pics dont work btw