Headers

[subie bob]

Ok so I'm sure this topic has been covered but I keep finding different answers. My question is i have a 2005 lgt im in the process of putting a jdm ej20 in ive been looking for headers and up pipe set that isn't a small fortune what is the difference between sets sold for sti/impreza and lgt's they appear to be the same to me 

[KZJonny]

Should all be the same for EJ20/25 series, but better to ask the manufacturer to be sure.

Sometimes they will not fit all oil pan shapes/pickup locations, but that is a solvable problem.

You won’t see much performance gain unless modified tho, especially with any of the ‘budget’ headers… So unless yours are damaged, UP/DP for better flow are your best bang for the dollar.

[subie bob]

1 hour ago, KZJonny said:

Should all be the same for EJ20/25 series, but better to ask the manufacturer to be sure.

Sometimes they will not fit all oil pan shapes/pickup locations, but that is a solvable problem.

You won’t see much performance gain unless modified tho, especially with any of the ‘budget’ headers… So unless yours are damaged, UP/DP for better flow are your best bang for the dollar.

I'm doing some upgrades beyond headers I've done cobb cai, silicone turbo inlet, bigger tmic, invidia dp, 3in exhaust, 20g turbo. The headers are the only thing I haven't found solid info on ive read that 02 through 05 wrx and any year sti headers will work but manufacturers say they won't and that i have to use headers for legacy and they are pretty pricey for legacy specific 

[KZJonny]

Someone more qualified than me will have something to say about it. I have holy headers, but a stock location turbo for a LGT, so it was never an issue for me. I just wanted EL headers and faster spool/efficiency.

Maybe you can get some information from whichever manufacturer you are leaning towards about what the fitment issue is for their manifold? Again, some do not list as compatible because they interfere with the oil pan. Oil pan/pickup can be swapped to the correct size/shape, but not you are getting to where you're spending money on a pan to make a cheaper manifold fit, instead of just shelling out money on the manifold in the first place.

There isn't a whole lot different in the very front of these cars by way of subframe and what have you that would make a header fit a WRX and not a LGT.

Not too many folks here are using JDM engines, it's just generally not preferred by the LGT crown unless it's because of budget constraints and you are using the more affordable 20x/y options when in a YNANSB situations. I guess there are more torque whores here or something. 

You might get a better answer at nastioc? Probably a lot more experience with people swapping to JDM 2.0L engines. This is assuming that there are not structural things in the way of the manifold, but I really don't think that is the case.

What are your expectation for spool up on a 2.0L engine with a 20G and aftermarket headers? I assume from that general combo you're looking for something that makes all the power way up in the RPM range?

[subie bob]

14 hours ago, KZJonny said:

Someone more qualified than me will have something to say about it. I have holy headers, but a stock location turbo for a LGT, so it was never an issue for me. I just wanted EL headers and faster spool/efficiency.

Maybe you can get some information from whichever manufacturer you are leaning towards about what the fitment issue is for their manifold? Again, some do not list as compatible because they interfere with the oil pan. Oil pan/pickup can be swapped to the correct size/shape, but not you are getting to where you're spending money on a pan to make a cheaper manifold fit, instead of just shelling out money on the manifold in the first place.

There isn't a whole lot different in the very front of these cars by way of subframe and what have you that would make a header fit a WRX and not a LGT.

Not too many folks here are using JDM engines, it's just generally not preferred by the LGT crown unless it's because of budget constraints and you are using the more affordable 20x/y options when in a YNANSB situations. I guess there are more torque whores here or something. 

You might get a better answer at nastioc? Probably a lot more experience with people swapping to JDM 2.0L engines. This is assuming that there are not structural things in the way of the manifold, but I really don't think that is the case.

What are your expectation for spool up on a 2.0L engine with a 20G and aftermarket headers? I assume from that general combo you're looking for something that makes all the power way up in the RPM range?

I'm doing a full build on the 2.5 that came out due to bad valves and p.o neglect. the ej20 is just going to be a place holder because of the length of time its going to take me to complete it my xj is a bit of a gas hog and driving it around a hundred miles a day is getting expensive

[KZJonny]

Ah!!

Nothing wrong with building a high RPM power band engine, but the 2.5L/20G combination makes more sense to me.

Up pipe is the same of all of the vf40/52 cars, so that should be easy at least, and getting rid of that catalytic is highly recommended. Good luck with the rebuild on the engine!