- Location
- Portland, OR
Here's a brief review of the Stillen headers I recently installed. Since I haven't had time to tune or fix the rest of my exhaust, I'm going to hold off on the full blown review and just post some comparison pics of the headers vs the oem manifolds, and the obvious things I've noticed since the installation. I'm going to have some work done to the rest of the exhaust next week, so I'll update this thread after that happens.
Stillen Equal Length Ceramic Coated Headers
Application: 2003-2008 FX35
Mfg part #: 508380M
Weblink: CLICK
Price: $555 from Stillen as of 1/13/12
Stillen headers vs OEM manifolds:

OEM manifold inlet port height = 1.054"

Stillen header inlet port height = 1.280"

OEM manifold inlet port width = 1.484" (1.228" sq)

Stillen header inlet port width = 1.612" (1.621" sq)

Outlet comparison:

OEM manifold outlet diameter = 1.685" (2.23" sq)

Stillen header outlet diameter = 1.861" (2.72" sq)

These measurements represent a net area increase of 32% @ the inlet ports and 22% @ the outlet. To be honest Im not really sure what that means, but it was interesting to me that the deltas were skewed...
IMPRESSIONS:
As I said above, I have yet to tune and the rest of my exhaust is currently hosed, so take these thoughts with a grain of salt as they could very well change next week. That said...
1) Startup is much more abrupt, in a good way. More of a "bark" and much more noticeable, but not really louder in terms of dB's.
2) Idle is MUCH quieter. This was really surprising to me, and at first I thought my ears were playing tricks due to the startup sound, but after a few days it is true. Idle is very noticeably quieter and sounds better to my ears in terms of tone.
3) Revs are much faster and feel easier. Again, the sound is different but not necessarily louder. More midrange than with the oem headers.
4) Drone is reduced across the board in normal driving circumstances.
5) Low end power feels pretty unaffected until about 3500rpm, at which time it pulls harder than before until redline. By far the most noticeable improvement is between 4500-6500 rpm.
OVERALL:
I am stoked. The install was rather brutal, but I really enjoy challenging installs. The fact that I did it myself and everything still works combined with the noticeable power improvements makes this a definite win-win for me. As for the power to dollar ratio, I'll report back when I get the rest of my ducks into a row.
Stillen Equal Length Ceramic Coated Headers
Application: 2003-2008 FX35
Mfg part #: 508380M
Weblink: CLICK
Price: $555 from Stillen as of 1/13/12
Stillen headers vs OEM manifolds:

OEM manifold inlet port height = 1.054"

Stillen header inlet port height = 1.280"

OEM manifold inlet port width = 1.484" (1.228" sq)

Stillen header inlet port width = 1.612" (1.621" sq)

Outlet comparison:

OEM manifold outlet diameter = 1.685" (2.23" sq)

Stillen header outlet diameter = 1.861" (2.72" sq)

These measurements represent a net area increase of 32% @ the inlet ports and 22% @ the outlet. To be honest Im not really sure what that means, but it was interesting to me that the deltas were skewed...
IMPRESSIONS:
As I said above, I have yet to tune and the rest of my exhaust is currently hosed, so take these thoughts with a grain of salt as they could very well change next week. That said...
1) Startup is much more abrupt, in a good way. More of a "bark" and much more noticeable, but not really louder in terms of dB's.
2) Idle is MUCH quieter. This was really surprising to me, and at first I thought my ears were playing tricks due to the startup sound, but after a few days it is true. Idle is very noticeably quieter and sounds better to my ears in terms of tone.
3) Revs are much faster and feel easier. Again, the sound is different but not necessarily louder. More midrange than with the oem headers.
4) Drone is reduced across the board in normal driving circumstances.
5) Low end power feels pretty unaffected until about 3500rpm, at which time it pulls harder than before until redline. By far the most noticeable improvement is between 4500-6500 rpm.
OVERALL:
I am stoked. The install was rather brutal, but I really enjoy challenging installs. The fact that I did it myself and everything still works combined with the noticeable power improvements makes this a definite win-win for me. As for the power to dollar ratio, I'll report back when I get the rest of my ducks into a row.