more power with JDM wrx heads?
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more power with JDM wrx heads?
I was wondering if and roughly how much power I will make over the stock with installing JDM wrx heads. They have the same size combustion chamber so my compression ratio will be the same. My supporting mods will be 3" catless turbo back, custom short ram intake, and 06 wrx TMIC.
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- Fifth Gear
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The point behind the 20G/K heads is that the valves are larger making flow better. On a regular 2.2T heads, you start to lose power at about 5300 ( this was dyno proved on my car) The G/K heads will allow flow way beyond that point. So instead of me shifting at 5300 ( peak power point) I could push the car to say 6500 rpms.
As for how much will you gain: it depends on the car and mods. But without a larger turbo, you will not see a major improvement, as the stock turbo is set-up to work with the stock heads. ( better power down low)
As for how much will you gain: it depends on the car and mods. But without a larger turbo, you will not see a major improvement, as the stock turbo is set-up to work with the stock heads. ( better power down low)
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No you can't have one
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Not by much, unless they are STi engines.AWD_addict wrote:The G/K engines also have a higher redline than the 22T. So with some EM you could have an even wider powerband.
The reason the Ej22T has the 6500 rpm redline that it does is that the head ports (and not the valve) restrict the air flow to the point that it's pointless to rev any higher. It just won't make power up there because it won't flow.
That said, given the powerband of a the Ej20G heads you don't suffer by using the stock Ej22t 6500 rpm redline. The JDM WRX only revs a couple of hundred rpms higher and over the years they've brought the redline back down to 6500 on our US cars.
Even with better flowing heads, the stock turbos (vf10 or td04) just don't push enough air to warrant going higher. High RPMs get treated like they are some magic pill. Rev higher = more power. Not true. It's only true under the right circumstances.
93GCsedan,
You'll probably pick up 30+chp by changing the heads and fiddling around with your boost a bit. This assumes that you are already or will be getting intercooled. You've got to change manifolds to do the heads, so if you can get the Ej20G injectors at the same time do it. Your stock ECU can run them fine even though they about 12% more than stock. If you install a FCD you can turn your boost up to about 1 bar and you'll be a really happy camper with that head swap. You'll be making stock WRX power in a car that weighs hundreds of pounds less.
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1973 Porsche 914 2.0 l -Suby swap pending
1968 Porsche 911t survivor 47k original miles
2000 2.5RS daily driver.
1999 2.5RS w/ 50+ extra whp
Suby Hai!
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Yep, check out some of the builds on this forum... The ones who actually have built motors make pretty damn good power.
Forged 2.2T + DOHC Headswap + right turbo = damn fine engine.
Forged 2.2T + DOHC Headswap + right turbo = damn fine engine.
~Spencer
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
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94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
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We all suck at tuning at first. If you read alot of different forums, alot of 'pros' apparently suck at tuning too.
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'93 Pure White SS EJ20G slanty intercooled, SIDESWIPED! In stasis.
'94 FWD and '95 AWD Laguna Blue SVXs.
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I should have clarified, I meant at the power levels we are talking about here (Stock WRXish power)PhyrraM wrote:We all suck at tuning at first. If you read alot of different forums, alot of 'pros' apparently suck at tuning too.
Nick
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1987 Audi 4000CS quattro...soon to be 20VT
1994 Dodge Ram 2500 4x4 CTD, #11 plate, 30 psi, Scotty II intake, 4" exhaust
Ah, Nick... okay, now that you clarified, that makes sense...
I was gonna say, Dave (non-forum person... ex-rallitek tech) rocks at Tuning, and he uses and swears by forged pistons.
I was gonna say, Dave (non-forum person... ex-rallitek tech) rocks at Tuning, and he uses and swears by forged pistons.
~Spencer
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
91 rhd Legacy Ti Type S 1.8
03 Lincoln LS V8 Sport
08 300 SRT8
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
91 rhd Legacy Ti Type S 1.8
03 Lincoln LS V8 Sport
08 300 SRT8
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Yes, forged are typically tougher than cast pistons, but its only necessary when you are pushing enough air to warrant them. Untill you move past a VF39 or 16g on a 22T you aren't there yet.
Even then, not all forged pistons are created equal. There is a reason CP pistons are almost twice as much as Wiseco's.
Even then, not all forged pistons are created equal. There is a reason CP pistons are almost twice as much as Wiseco's.
→Dan
piddster34 at h0tma1l d0t c0m
piddster34 at h0tma1l d0t c0m
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I'm not saying it cannot be done with a piggyback. It's just that not having full control over timing handicaps you. You want to ask a VF39 for everything it has, and without the ability to control everything like you can with a standalone or a modern ECU with open-source tuning, you will have a tough time doing so reliably.
Piggy-back units like the e-manage, PP6, Maf T Pro, etc, are not standalones, and aren't even close. The software may be there, but you are still dependant on the factory ECU for ignition and injector drivers, among other things. Therefore, you cannot call any piggyback an almost-standalone.
In no way, shape or form am I trying to dog you or sway you from a piggy back. I'm just trying to bring everything to your table in reality.
If you can make it happen, I say more power to you.
Piggy-back units like the e-manage, PP6, Maf T Pro, etc, are not standalones, and aren't even close. The software may be there, but you are still dependant on the factory ECU for ignition and injector drivers, among other things. Therefore, you cannot call any piggyback an almost-standalone.
In no way, shape or form am I trying to dog you or sway you from a piggy back. I'm just trying to bring everything to your table in reality.
If you can make it happen, I say more power to you.
→Dan
piddster34 at h0tma1l d0t c0m
piddster34 at h0tma1l d0t c0m
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- Fifth Gear
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A good tuner can tune something no matter what brand of EM it is. Fuel is fuel, and timing is timing. If they say they only do AEM or something like that, stay away.
Its not hard to find management with good control. What is hard to find is cheap management with good control.
Its not hard to find management with good control. What is hard to find is cheap management with good control.
→Dan
piddster34 at h0tma1l d0t c0m
piddster34 at h0tma1l d0t c0m