STI Coils on Phase I Heads

hustleshark206 · 01-13-2010, 08:51 PM

Does anyone know if STI coil over plug coils will fit Phase I DOHC cylinder heads? I simply couldn't tell if the boot was engauging the plug or not. It is awful close. I have heard that the STI and WRX COP coils might differ slightly in length but I am looking for confirmation one way or another.

STI coils have built in ignitors correct?

Thanks guys

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ciper · 01-13-2010, 09:32 PM

Which STI? Which phase 1 heads?

dr3w · 01-13-2010, 10:46 PM

Post this is the stickyed coil conversion thread in the pre 2002 section of forum.

But if i remember right yes you can.

ciper · 01-13-2010, 10:51 PM

Quote:

Originally Posted by dr3w

But if i remember right yes you can.

So I could take the coils from a 98 STI and put them on some Legacy Turbo heads?

sense of nature · 01-13-2010, 10:57 PM

Quote:

Originally Posted by ciper

So I could take the coils from a 98 STI and put them on some Legacy Turbo heads?

Good luck getting them to fire correctly tho

ciper · 01-14-2010, 01:11 AM

Quote:

Originally Posted by sense of nature

Good luck getting them to fire correctly tho

Igniter bypass mod

suberdave · 01-14-2010, 01:44 AM

wouldnt a 98 STI be a EJ20K with a single coil pack?

if he is talking about a USDM trubo legacy this may work. but not sure. but deff. not the same as the coil mod for the phase I DOHC and USDM STI coil packs...

-=Suberdave=-

hustleshark206 · 01-14-2010, 02:44 AM

Thanks guys. I am talking about USDM STI coils from a 2005. The cylinder Heads are DOHC from a 98 2.5RS. I am going stand alone with a haltech platinum sport 1000. Haltech told me I could wire them straight to the ECU no problems but then again they are Aussy.

ciper · 01-14-2010, 03:00 AM

I actually knew you meant EJ257 style heads and EJ25D heads but decided to take a big dump on your thread for being unclear

EJ25D heads are actually the same as EJ20G heads. It would probably helped you more if you searched about EJ20G heads with EJ257 coils.

edit: Ok I am feeling generous - this thread may help you http://forums.nasioc.com/forums/show....php?t=1192028

hustleshark206 · 01-14-2010, 03:07 AM

Ok I will try searching for that. Or you could just tell me since I don't know **** and you are the man.

hustleshark206 · 01-14-2010, 12:16 PM

HAHA thanks Ciper.

hustleshark206 · 01-14-2010, 03:04 PM

One more quick question. Ciper told me EJ25D and EJ20G heads are the same thing. Is there any difference in the spark plugs used? I am sure the gap will be different one being N/A and one turbo but is the plug itself different?

DSM_Outback · 01-14-2010, 03:09 PM

Heat range will be different. EJ25D=BKR5ES EJ20G=BKR6ES (factory)

hustleshark206 · 01-14-2010, 03:48 PM

Perfect. Thanks guys!

dr3w · 01-14-2010, 04:27 PM

Quote:

Originally Posted by DSM_Outback

Heat range will be different. EJ25D=BKR5ES EJ20G=BKR6ES (factory)

Factory oem for ej20g is actually pfr6g's but brk6e's also work.

hustleshark206 · 01-14-2010, 08:13 PM

After reading about cylinder heads all day it seems that the EJ20G heads are the same as MY96 EJ25D heads. MY98 EJ25D heads are more like EJ20K or EJ20H. All these numbers are getting confusing LOL! All I want to know is will the STI coils engauge the spark plug in MY98 EJ25 DOHC heads. Everything I have read suggests they will but when I test fitted them I couln't tell. Could the EJ20 spark plug be physically longer I wonder?

Fuji Where you at bro?

jamal · 01-14-2010, 08:36 PM

wrx coil packs should fit but the sti ones are a different length. You can pull the ends off and swap them though.

DSM_Outback · 01-14-2010, 11:29 PM

Quote:

Originally Posted by dr3w

Factory oem for ej20g is actually pfr6g's but brk6e's also work.

Platinum sucks.

suberdave · 01-15-2010, 12:42 AM

Quote:

Originally Posted by jamal

wrx coil packs should fit but the sti ones are a different length. You can pull the ends off and swap them though.

i have heard this many times. however i have been using STI coil packs on my EJ20G for 12K and they seem to work just fine...

does someone have a pic of an STI coilpack next to a WRX coilpack?

-=Suberdave=-

hustleshark206 · 01-15-2010, 11:27 AM

^ yeah this would really help. I have read that they are different lengths but then everyone says they are interchangable. I don't get it.....

ciper · 01-15-2010, 08:07 PM

I've seen my02 WRX coils next to my05 STI coils and they looked the same to me other than the colors. I didn't specifically measure them though.

This thread originally peaked my interest because I plan to use coil on plugs with my DOHC NA engine which has the EJ25D heads.

hustleshark206 · 01-16-2010, 04:05 PM

Quote:

Originally Posted by ciper

I've seen my02 WRX coils next to my05 STI coils and they looked the same to me other than the colors. I didn't specifically measure them though.

This thread originally peaked my interest because I plan to use coil on plugs with my DOHC NA engine which has the EJ25D heads.

Bmxpunk confirmed that they will work because he is currently using EJ22t block MY98 DOHC heads and STI coils. I am trying to find out what plugs he is using.

bmxpunk · 01-17-2010, 01:26 AM

Quote:

Originally Posted by hustleshark206

Bmxpunk confirmed that they will work because he is currently using EJ22t block MY98 DOHC heads and STI coils. I am trying to find out what plugs he is using.

NGK Bkr6es (vf37turbo, 14psi, 8.5:1CR) I will switch to 7's someday when I make more power

hustleshark206 · 01-18-2010, 03:41 PM

Thanks BMX! I will try those plugs and see if that helps

jamal · 01-28-2010, 12:45 AM

Quote:

Originally Posted by suberdave

i have heard this many times. however i have been using STI coil packs on my EJ20G for 12K and they seem to work just fine...

does someone have a pic of an STI coilpack next to a WRX coilpack?

-=Suberdave=-

been awhile but I grabbed two coilpacks the other day and took a picture:

sti coilpack is the short one.

01-13-2010, 08:51 PM	#1
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	STI Coils on Phase I Heads Does anyone know if STI coil over plug coils will fit Phase I DOHC cylinder heads? I simply couldn't tell if the boot was engauging the plug or not. It is awful close. I have heard that the STI and WRX COP coils might differ slightly in length but I am looking for confirmation one way or another. STI coils have built in ignitors correct? Thanks guys * Registered users of the site do not see these ads.

01-14-2010, 03:00 AM	#9
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Location: san francisco, ca Vehicle: 90BJ Legacy LS ABS AWD 946 Rio Red Jpn built	I actually knew you meant EJ257 style heads and EJ25D heads but decided to take a big dump on your thread for being unclear EJ25D heads are actually the same as EJ20G heads. It would probably helped you more if you searched about EJ20G heads with EJ257 coils. edit: Ok I am feeling generous - this thread may help you http://forums.nasioc.com/forums/show....php?t=1192028 Last edited by ciper; 01-14-2010 at 03:07 AM.

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01-13-2010, 09:32 PM	#2
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Location: san francisco, ca Vehicle: 90BJ Legacy LS ABS AWD 946 Rio Red Jpn built	Which STI? Which phase 1 heads?

01-13-2010, 10:46 PM	#3
dr3w Scooby Specialist Member#: 222318 Join Date: Sep 2009 Chapter/Region: E. Canada Location: Montreal Vehicle: 1993 RHD GC8 Silver	Post this is the stickyed coil conversion thread in the pre 2002 section of forum. But if i remember right yes you can.

01-14-2010, 01:44 AM	#7
suberdave NASIOC Supporter Member#: 101865 Join Date: Nov 2005 Chapter/Region: NWIC Location: Covington, WA Vehicle: 88 GL-10 STi silver	wouldnt a 98 STI be a EJ20K with a single coil pack? if he is talking about a USDM trubo legacy this may work. but not sure. but deff. not the same as the coil mod for the phase I DOHC and USDM STI coil packs... -=Suberdave=-

01-14-2010, 02:44 AM	#8
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	Thanks guys. I am talking about USDM STI coils from a 2005. The cylinder Heads are DOHC from a 98 2.5RS. I am going stand alone with a haltech platinum sport 1000. Haltech told me I could wire them straight to the ECU no problems but then again they are Aussy.

01-14-2010, 03:07 AM	#10
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	Ok I will try searching for that. Or you could just tell me since I don't know **** and you are the man.

01-14-2010, 12:16 PM	#11
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	HAHA thanks Ciper.

01-14-2010, 03:04 PM	#12
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	One more quick question. Ciper told me EJ25D and EJ20G heads are the same thing. Is there any difference in the spark plugs used? I am sure the gap will be different one being N/A and one turbo but is the plug itself different?

01-14-2010, 03:09 PM	#13
DSM_Outback Scooby Specialist Member#: 56345 Join Date: Mar 2004 Location: Western Colorado Vehicle: 93 Swapped L Green	Heat range will be different. EJ25D=BKR5ES EJ20G=BKR6ES (factory)

01-14-2010, 03:48 PM	#14
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	Perfect. Thanks guys!

01-14-2010, 08:13 PM	#16
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	After reading about cylinder heads all day it seems that the EJ20G heads are the same as MY96 EJ25D heads. MY98 EJ25D heads are more like EJ20K or EJ20H. All these numbers are getting confusing LOL! All I want to know is will the STI coils engauge the spark plug in MY98 EJ25 DOHC heads. Everything I have read suggests they will but when I test fitted them I couln't tell. Could the EJ20 spark plug be physically longer I wonder? Fuji Where you at bro?

01-14-2010, 08:36 PM	#17
jamal Scooby Guru Member#: 71875 Join Date: Oct 2004 Location: Montana Vehicle: 98 2.5GT my wheels fit	wrx coil packs should fit but the sti ones are a different length. You can pull the ends off and swap them though.

01-15-2010, 11:27 AM	#20
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	^ yeah this would really help. I have read that they are different lengths but then everyone says they are interchangable. I don't get it.....

01-15-2010, 08:07 PM	#21
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Location: san francisco, ca Vehicle: 90BJ Legacy LS ABS AWD 946 Rio Red Jpn built	I've seen my02 WRX coils next to my05 STI coils and they looked the same to me other than the colors. I didn't specifically measure them though. This thread originally peaked my interest because I plan to use coil on plugs with my DOHC NA engine which has the EJ25D heads.

01-18-2010, 03:41 PM	#24
hustleshark206 Scooby Specialist Member#: 182227 Join Date: Jun 2008 Chapter/Region: NWIC Location: seattle, WA/ Jackson WY Vehicle: 2000 MPS Built RS 1991 Leggy Turbo EJ22t	Thanks BMX! I will try those plugs and see if that helps