I received this header last month but just got around to installing them. I also got these Jet Hot coated. So here's a quick run down on them.

Build
What can I say, it's Top notch. The bends, weld, and the coating were all very well done.

Fitment
Close to perfect. I had a buddy help me. We had to wiggle a little bit to first get them on, then bang it a couple of times with a rubber mallet. It line up great with the Up-Pipe and the to the block.

Sound
Once I turned it on I notice my exhaust tone changed. There was more rumbling, but it was not as deep. It got more hollow. This was a bit disappointing for me, as to I prefer the exhaust note to be deep. But I am happy that I kept the rumbling sound.

Performance
As soon as I took it for a test drive I notice the car just wanted to go into boost. :eek: Spooling was noticeably increased. The turbo wooshing sound comes on alot earlier and louder. Even my girlfriend noticed it. I can also feel that from mid to high rpm has improved. I'm push a little more into the seat. On the highway in 4th-6th gear the slightest touch on the pedal will send the turbo spooling into full boost. The car also breaths so much better. I couldn't believe how much smoother it drives. I love the way it drives now.

Other than the sound, I was very disappointed that I did not received gaskets with it, eventhough on Gruppe-S website says it comes with it. To make matters worst I first called Gruppe-S to ask if gaskets were suppose to come with it, they said no. I later read on IWSTI they were suppose to and that it states it on Gruppe-s website. I called Gruppe-s to send me my gaskets, they said sure and that they will include them with my SMC meth kit I ordered. My SMC kit came and no gaskets. So I PM them and they said sorry will get them out to you. About 8 days pass by, still no gaskets. So I PM them again and they said they did, they have no way of tracking it, and to notify them when I do receive them. Well its been two weeks and still no gaskets.

Overall I'm happy with them and would recommend these headers. Now for a tune. :devil:

On a side note. The only I found annoying doing this install was the removing and putting back the o2 sensor. It was in a tight spot.

I will be adding: GM boost solenoid, SMC meth kit, SSAC TMIC, and fuel pump. Then hope to get tuned by Scott Siegel.

My mods before the headers are: Megan DP wrapped, HKS CB, turbo heat shield, and Cobb AP w/stage 2 map.

I would like to thank I'M SLOW for his help.

I just installed my Gruppe-S header and I couldn't be happier with the quality, fitment, and performance. Took me about 2 hours to take off my exhaust manifold and install the header. No fitment issues at all, went straight on. The hardest part was the o2 sensor, like stated above. So before I got tuned for it I did some logs and no knock correction and it wasn't pulling timing. I took it out to the track today to see how it would do untuned and I gained almost 2 mph, from a 107 to a 109 and ran a best of 12.50 (previous best was 12.6). Great product.

2mph, I like that. hmmm datelog, i should do that to make sure im not in any danger zone. i do have both egt and wideband that i've been monitoring. and those seem good when i floor it.

another note about the Sound. it's gotten noticeably quieter. at idel, revving, and crusing.

with the installation I recommend 2 people, but it's managable with one. and it doesnt take long. 2-3 hrs taking your time. that includes jacking up the car, taking off the stock headers, replacing it with new, and clean up everything afterwards.

was a very easy install, pretty much flawless. Now it's time to do mine this weekend:)

I got mine about a year ago, fitament was a little tight onto the heads, but lined up to my uppipe perfectly

quality is top notch, price is untouchable

only complaint i had was the raspyness, but now having it on a 2.5 with cams you dont even notice the rasp as much anymore.

Power gains and turbo spool outweighs the sound, as always " perfromance > * "

On their site it says that for the EJ20 i'll lose some low end power and gain mid to high end power, anyone have any experience with this?
Is it worth it to get the coating?

I think the less is negligable, i had it on my 2.0 for a while and didnt notice too much

I dont have the coating, but i do reccomend it (what a hypocrit!)