Hybrid or 2.5 sti heads

Samiam1017 · 10-10-2012, 08:25 AM

I have a 05 wrx that spun a bearing. I purchased a factory 257 short block. I'm on a budget so my question is, what's the best way to go. Could I use the ecu I have (of coarse with a tune) with the sti heads. If I go the hybrid route I could either do the hybrid forged pistons or have my 2.0 heads refreshed and cnc'ed but I cant do both right now. What's the safest way to go. I'm looking for a quick spool up and max of 350hp ( down the road with supporting mods) . Yes I have read tons of hybrid post and know there's issues and it's not cheap. I'm looking for recommendations on where to start,reliable shops in the northeast. Thx

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Purpose_Built · 10-23-2012, 10:53 AM

Forged pistons on your stock heads. You will have to work out crank breather issues if you dont use the ej257 vent system. I've been running mine for a while and the only thing really f'd is my transmission.

Samiam1017 · 10-23-2012, 11:22 AM

Thx for the reply, didn't think I was gonna get any. What pistons did you go with. Size? Not drop in right. Head gasket? Did you do anything to the heads? Thx again

wrxsubiemod · 10-23-2012, 11:46 AM

Does your 257 already have the heads? Is it a used block and heads? Is it already assembled?

danger1138 · 10-23-2012, 11:51 AM

If you got the 2.5 heads i would just use those. And worry about just getting the ecu. With the hybrid u need to do head work on the 2.0 heads and worry about all the misc little stuff thats specific to the 2.0 & 2.5 like gasket kits..

Samiam1017 · 10-23-2012, 11:59 AM

It's a brand new 257 short block. I was gonna use my 20 heads. If I go with the proper 2.5 heads I need a 05 ecu ? Or can the ecu I have he tuned with an access port. Also if I go the 2.5 head route what years/ models work. Any model with better cams?

mlitz · 10-23-2012, 12:40 PM

They make a bracket to fit you 2.0l cam sensor on the 2.5 heads no need to get the ecu. but you will need to get it tuned and the 2.0l ecu wont know what to do with the extra .5l

wrxsubiemod · 10-23-2012, 12:49 PM

2.0 heads

You can port the combustion chamber or you will need thicker head gaskets. I would also recommend running sti cams while your there.

2.5 heads

you will need to plug avcs cams and run wrx cam gears. Some heads have a spot for the cam sensor but if they don't you can buy a braket from cosworth.

Both setups need a tune and both will get you to where u need to be

Samiam1017 · 10-23-2012, 01:47 PM

Stupid question. Is there different model/part number heads to look for or are all 2.5 the same. Also the car is a 05 so if I wants a ecu then I would need an 05 sti ecu? I'm right that they changed harrnesses year to year. I think I'm gonna look at the proper heads instead of hybrid. I think that would be way more expensive and a nightmare I don't need right now. Everbody thx for your advice!

Evan · 10-23-2012, 02:18 PM

How much are complete 2.5L heads going for?

wrxsubiemod · 10-23-2012, 03:48 PM

You don't need to change ecus. You would just need to get a proper tune.

Purpose_Built · 10-25-2012, 01:49 PM

You need a sti head gasket but everything else is for the ej20 as far as gaskets go. I decided on the ej20 head just to save money. The only reason i would run a sti head is to use the sti pcv setup. Using the ej20 head will leave you money for porting or valve springs and valves

SunnyDWrx · 11-02-2012, 02:52 PM

How much of a tune difference would there be if you did this setup with the 565cc injectors and 255lph fuel pump? Would it even start up and run well enough to tune? Or do you need a completely different initial tune to start with before you can fine tune?

04ScoobyWtf · 11-02-2012, 03:13 PM

My tuner said it'll be fine for me because that's what I'm doing on my startup. The e u can compensate for 25% for or less flow so 440-565 is about 25% you'll e running pig rich just don't get on it or get in boost. I'm driving 3 hours to get my tune like that

triniscoob · 11-02-2012, 09:43 PM

Quote:

Originally Posted by Purpose_Built

Forged pistons on your stock heads. You will have to work out crank breather issues if you dont use the ej257 vent system. I've been running mine for a while and the only thing really f'd is my transmission.

Curious but exactly what are the known crank breaher issues with the hybrid?

Purpose_Built · 11-03-2012, 02:51 PM

Quote:

Originally Posted by triniscoob

Curious but exactly what are the known crank breaher issues with the hybrid?

People block off the center crank breather port since the bugeyes (dont know about others) use a different pcv setup. It causes excess pressure and you may notice oil being burned at an accelerated rate.

If you plan to go above 400 get your heads modded or mod it yourself and get cams. This is just to get the combustion chamber back inline with what subaru intended. Cars that are stressed more would really need this. I promise you don't need to get your heads modded to run a hybrid. Two months ago i picked up a set of wrx heads with covers for 150. I didnt even want them or need them but there they were. Try finding that price with STI heads

The stock cams suck and my car falls on its face close to 7k with a 8cm td06h/60-1. Just purchased some 280's which are overkill but i had a lot of leftover money. Find some used 264 and it will make an awesome street car

My suggestion to you.

Forged Pistons 99.75
Arp head studs (not needed but cheap insurance)
Arp rod bolts (My car spins and rod bolts will stretch/snap)
Bearings (you should already have new ones)
Springs (optional)
Sti Cams or 264's if you want power to the right side of the graph
Sti rods
Use a new oil pump, use a new oil pump, use a new oil pump, use a new oil pump.....use a new oil pump
Use a new heat exchanger or delete it since its mainly for emissions purposes
Lap the valves and check the guide clearance
Install new valve seals

I did so much at once to mine because the engine is a pain in the ass to get out. This is fairly cheap if you do all of the work yourself

Your car will run very ****ty and some folks cars wont run at all but it really is a guessing game. It could be changes in elevation because my car would not run initially. It would put once or twice and then tell me to **** off.

spackyscooby · 11-03-2012, 04:21 PM

NOOB question, but rather than blocking the second/center breather would it be better to put a hose coming off it running to the pcv on the intake manifold and then have the one that all cars have running to the inlet like normal, or bring the 2 lines together then into a catch can then into the inlet and plugging the hole for the pcv on the I.M. getting rid of it completely? Or is there a better way to do it that I have not thought of yet?

triniscoob · 11-15-2012, 12:23 PM

Quote:

Originally Posted by Purpose_Built

People block off the center crank breather port since the bugeyes (dont know about others) use a different pcv setup. It causes excess pressure and you may notice oil being burned at an accelerated rate.

If you plan to go above 400 get your heads modded or mod it yourself and get cams. This is just to get the combustion chamber back inline with what subaru intended. Cars that are stressed more would really need this. I promise you don't need to get your heads modded to run a hybrid. Two months ago i picked up a set of wrx heads with covers for 150. I didnt even want them or need them but there they were. Try finding that price with STI heads

The stock cams suck and my car falls on its face close to 7k with a 8cm td06h/60-1. Just purchased some 280's which are overkill but i had a lot of leftover money. Find some used 264 and it will make an awesome street car

My suggestion to you.

Forged Pistons 99.75
Arp head studs (not needed but cheap insurance)
Arp rod bolts (My car spins and rod bolts will stretch/snap)
Bearings (you should already have new ones)
Springs (optional)
Sti Cams or 264's if you want power to the right side of the graph
Sti rods
Use a new oil pump, use a new oil pump, use a new oil pump, use a new oil pump.....use a new oil pump
Use a new heat exchanger or delete it since its mainly for emissions purposes
Lap the valves and check the guide clearance
Install new valve seals

I did so much at once to mine because the engine is a pain in the ass to get out. This is fairly cheap if you do all of the work yourself

Your car will run very ****ty and some folks cars wont run at all but it really is a guessing game. It could be changes in elevation because my car would not run initially. It would put once or twice and then tell me to **** off.

i currently have a recently rebuilt Hybrid, EJ257 block and EJ207 heads, what exactly do you mean by modding th head? and when you say to change cams? you simply means to put in cams with higher lift and duration ?

Yes i am having excessive crank case pressure that builds up a few moments after starrting initially but it does seem to subside after warming up, currently i have 2 oy the side head breathers going into a grimmspeed and then the return line going towards the turbo inlet, the other 2 breathers off the head are "T" ed together and my center Crank case breather is vented to ATM, without any idle problems or vaccumm problmes.

what would you recommend?

Texy32 · 11-25-2012, 02:05 PM

These guy are talking about USDM EJ205 heads. the valve cover only has one breather. This is not the case with EJ207 heads because they come with 2 breathers on each valve cover like the USDM EJ257 Heads. So this does not apply to you.

. o 69 o . · 11-25-2012, 05:56 PM

I am looking at this as well. if using the ej257 heads (single avcs) vs the 2L heads, can I just use my 2L intake and associated parts, change the ej257 cams for a non avcs higher lift and duration cam, maybe a crower or something like that, and tune it?

10-10-2012, 08:25 AM	#1
Samiam1017 Scooby Newbie Member#: 334068 Join Date: Oct 2012 Location: North eastern pa.	Hybrid or 2.5 sti heads I have a 05 wrx that spun a bearing. I purchased a factory 257 short block. I'm on a budget so my question is, what's the best way to go. Could I use the ecu I have (of coarse with a tune) with the sti heads. If I go the hybrid route I could either do the hybrid forged pistons or have my 2.0 heads refreshed and cnc'ed but I cant do both right now. What's the safest way to go. I'm looking for a quick spool up and max of 350hp ( down the road with supporting mods) . Yes I have read tons of hybrid post and know there's issues and it's not cheap. I'm looking for recommendations on where to start,reliable shops in the northeast. Thx * Registered users of the site do not see these ads.

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10-23-2012, 10:53 AM	#2
Purpose_Built NASIOC Supporter Member#: 222879 Join Date: Sep 2009 Chapter/Region: Tri-State Location: NJ Vehicle: 2003 WRX Silver	Forged pistons on your stock heads. You will have to work out crank breather issues if you dont use the ej257 vent system. I've been running mine for a while and the only thing really f'd is my transmission.

10-23-2012, 11:22 AM	#3
Samiam1017 Scooby Newbie Member#: 334068 Join Date: Oct 2012 Location: North eastern pa.	Thx for the reply, didn't think I was gonna get any. What pistons did you go with. Size? Not drop in right. Head gasket? Did you do anything to the heads? Thx again

10-23-2012, 11:46 AM	#4
wrxsubiemod Scooby Specialist Member#: 165104 Join Date: Nov 2007 Chapter/Region: SCIC Location: name where you like it Vehicle: E85 bug-i sti swap Phatron tuned	Does your 257 already have the heads? Is it a used block and heads? Is it already assembled?

10-23-2012, 11:51 AM	#5
danger1138 Scooby Specialist Member#: 279525 Join Date: Apr 2011 Location: QUEENS NY Vehicle: 04 rex luger!	If you got the 2.5 heads i would just use those. And worry about just getting the ecu. With the hybrid u need to do head work on the 2.0 heads and worry about all the misc little stuff thats specific to the 2.0 & 2.5 like gasket kits..

10-23-2012, 11:59 AM	#6
Samiam1017 Scooby Newbie Member#: 334068 Join Date: Oct 2012 Location: North eastern pa.	It's a brand new 257 short block. I was gonna use my 20 heads. If I go with the proper 2.5 heads I need a 05 ecu ? Or can the ecu I have he tuned with an access port. Also if I go the 2.5 head route what years/ models work. Any model with better cams?

10-23-2012, 12:40 PM	#7
mlitz Scooby Newbie Member#: 293571 Join Date: Sep 2011 Chapter/Region: NWIC Location: Vancouver Vehicle: 1997 Legacy GT Murdered	They make a bracket to fit you 2.0l cam sensor on the 2.5 heads no need to get the ecu. but you will need to get it tuned and the 2.0l ecu wont know what to do with the extra .5l

10-23-2012, 12:49 PM	#8
wrxsubiemod Scooby Specialist Member#: 165104 Join Date: Nov 2007 Chapter/Region: SCIC Location: name where you like it Vehicle: E85 bug-i sti swap Phatron tuned	2.0 heads You can port the combustion chamber or you will need thicker head gaskets. I would also recommend running sti cams while your there. 2.5 heads you will need to plug avcs cams and run wrx cam gears. Some heads have a spot for the cam sensor but if they don't you can buy a braket from cosworth. Both setups need a tune and both will get you to where u need to be

10-23-2012, 01:47 PM	#9
Samiam1017 Scooby Newbie Member#: 334068 Join Date: Oct 2012 Location: North eastern pa.	Stupid question. Is there different model/part number heads to look for or are all 2.5 the same. Also the car is a 05 so if I wants a ecu then I would need an 05 sti ecu? I'm right that they changed harrnesses year to year. I think I'm gonna look at the proper heads instead of hybrid. I think that would be way more expensive and a nightmare I don't need right now. Everbody thx for your advice!

10-23-2012, 02:18 PM	#10
Evan Scooby Specialist Member#: 11218 Join Date: Oct 2001 Chapter/Region: SCIC Location: Orange, CA Vehicle: 2005 Legacy GT Wagon 99 Miata, 91 Miata turbo	How much are complete 2.5L heads going for?

10-23-2012, 03:48 PM	#11
wrxsubiemod Scooby Specialist Member#: 165104 Join Date: Nov 2007 Chapter/Region: SCIC Location: name where you like it Vehicle: E85 bug-i sti swap Phatron tuned	You don't need to change ecus. You would just need to get a proper tune.

10-25-2012, 01:49 PM	#12
Purpose_Built NASIOC Supporter Member#: 222879 Join Date: Sep 2009 Chapter/Region: Tri-State Location: NJ Vehicle: 2003 WRX Silver	You need a sti head gasket but everything else is for the ej20 as far as gaskets go. I decided on the ej20 head just to save money. The only reason i would run a sti head is to use the sti pcv setup. Using the ej20 head will leave you money for porting or valve springs and valves

11-02-2012, 02:52 PM	#13
SunnyDWrx Scooby Newbie Member#: 331714 Join Date: Sep 2012 Location: Pennsylvania Vehicle: 2004 Wrx Silver	How much of a tune difference would there be if you did this setup with the 565cc injectors and 255lph fuel pump? Would it even start up and run well enough to tune? Or do you need a completely different initial tune to start with before you can fine tune?

11-02-2012, 03:13 PM	#14
04ScoobyWtf Scooby Newbie Member#: 287974 Join Date: Jul 2011	My tuner said it'll be fine for me because that's what I'm doing on my startup. The e u can compensate for 25% for or less flow so 440-565 is about 25% you'll e running pig rich just don't get on it or get in boost. I'm driving 3 hours to get my tune like that

11-03-2012, 04:21 PM	#17
spackyscooby Scooby Newbie Member#: 169257 Join Date: Jan 2008 Location: Idaho Vehicle: 2000 impreza rs millenium jade	NOOB question, but rather than blocking the second/center breather would it be better to put a hose coming off it running to the pcv on the intake manifold and then have the one that all cars have running to the inlet like normal, or bring the 2 lines together then into a catch can then into the inlet and plugging the hole for the pcv on the I.M. getting rid of it completely? Or is there a better way to do it that I have not thought of yet?

11-25-2012, 02:05 PM	#19
Texy32 Scooby Specialist Member#: 124252 Join Date: Aug 2006 Chapter/Region: TXIC Location: Houston, TX Vehicle: 0506 STI/Tribeca OBP/SGM	These guy are talking about USDM EJ205 heads. the valve cover only has one breather. This is not the case with EJ207 heads because they come with 2 breathers on each valve cover like the USDM EJ257 Heads. So this does not apply to you.

11-25-2012, 05:56 PM	#20
. o 69 o . Scooby Newbie Member#: 124938 Join Date: Sep 2006	I am looking at this as well. if using the ej257 heads (single avcs) vs the 2L heads, can I just use my 2L intake and associated parts, change the ej257 cams for a non avcs higher lift and duration cam, maybe a crower or something like that, and tune it?