Csquared: all i can said is go for it! Read G37driver.they have alot of answer and info you need to know.Let me know after you've done yur install.
Go step by step!!!!

wow just finished reading this thread from begging to end. I one of the 10 who also went into the group buy, I hope these issues don't come up when I install them. I'll keep you guys updated.

I took my car in Prime in Hanover MA. Cause thats were a got the car. Herb Chambers I would buy a car from them if they were the last dealer on earth and Norwood changed the deal right at the last second so I walked. The funny thind about my car is it accualy came forem Norwood it is the exact car I drove and was going to but from them till they changed the deal..

Also I said the feild tech mentioned the o2 sensor locatin. Well the servie manager gave me a the link to hopup Racing and told me something about the secondary wide band sensor port.. LOL They could even explain it to me.. I bet they have no clue what it is or does. He also showed mo the springs that are in the O2 ports, but Berk told me that those are there to keep some of the exhaust flow off the stock sensors and to keep the CEL's off.

Probally will look into the Tanbe exhaust. I know it's only a axle back but I love their products and the sound. + Boston PO's are pains in the butt to modded cars. If I want a full cat back I could go to a local muffler shop and have them build pipes bacl to the Mufflers. But I love the Tanbe.

My G37x was swapped this morning for a loaner '07 G35x. My car was driven to the dealership.

I spoke with the service advisor at around 5:00pm this evening about what the regional service expert found after looking over my car today. He found nothing amiss—no surprise. However, the regional rep told the service advisor to tell me that I may have depressed both the brake and accelerator at the same time, which causes the car to go into limp mode. I suspect that’s what the regional rep thinks happened, unless something more sinister (read “cover up”) is going on.

The service advisor told me that depressing both at the same time will put a G into limp mode immediately. (Anyone know about this?) So, I attempted it with the G35x loaner I was driving. I attempted it from a standing start, I attempted it while at a about 5-10 mph, and I attempted it at about 20 mph—all to no effect. Further, the advisor said that as soon as the brake is applied when the car is in limp mode following this brake and accelerate pattern, the car immediately leaves limp mode and operates properly. No matter what I did during the actual incidents with my car—from braking and accelerating while moving as well as when in neutral—nothing “cured” the car of limp mode.

I do not believe that I did that at the time of the incidents anyway. Each was from a standard stop. In any case, I do not believe that my car went into limp mode because of this brake and accelerate theory. I was accelerating only.

So, my car will be returned to me tomorrow (Tuesday) with nothing found. I was told that if the problem should happen again, they will supply me with a sort of black box (like on an airplane) that will monitor the car at all times. Of course, I expressed reservations about driving the car since nothing has been found. I also said that if nothing happens after a month of driving, I will begin to relax my fears and family driving restrictions—my wife doesn’t now drive it, and I don’t let my kids in the car either.

And that’s the way it is today. They will swap my car back in the morning. Comments? Suggestions?

Hmmm... I've been an idiot with my friends in a parking lot after a nice snow storm and we go do donuts and drifts, etc, we make sure no cars around or anything, but I've gone like 40 mashed the brake as i accelerate to swing the tail out into a nice drift and nothing happens lol.

I'm not sure if I'd agree with the accelerator brake peddle theory, just last week I spent like 10min doing it to my car and nothing happened. Never hit limp mode ever, hope this helps. Oh and I was doing this at a standing start

I think like you that is just a excuse for " We have no fn clue what wrong". But your car did not do it when they had it. That sux.

Okay Just got back from the dealership with the cats installed.

This is what i think so far,
sound wise, there is a little gain in sound, not much, not like a a g35 coupe, it's closer not it's not the same sound, or as loud. My friend was like it's apparent that is' deeper (a little) and that when you step on it a little higher pitched. But the engine with the intakes is still way louder then the exhaust.

They weigh less than half the stock cats if you're into weight saving.

As for power, i can tell that there is a difference. Butt dyno said yes.

Side note - There is a like a grinding or hissing sound or something, my friend said once you change exhausts it's like that his 335i does it so my friends m3 did it to before he got the gtr. Does yours do it earth0?

I'll talk about this more later, I'm tired and hungry hahaahah.

Overall I'm happy with it, wish it gave more sound!

And no i'm not getting hesitation like anmvq, touch on wood that it doenst' happen. I think car is even more responsive than before.

MM No issues EH?? We have the same car mine was ready to blow up and you have no problems at all???

SO far so good, no blowingup yet, I hope it doenst want to blow up soon, I jsut resetting the ECU today, hope that doenst' screw things up. hahahaha.

Glad you like it. i hope all i had been telling you guy was right.there is no blow up or anything at all.HFC's is not really the cause direct to transmission as the stealer had mention to ANMV. i guess we just have to wait for Csquared to confirm after using BERK's for couple month.

I realy hope so. I hope no one deals with what I did. But my issue with in a weeks time. But glad toi hear you like it and have no issues yet. Good luck.

I will keep you guys posted, now i just need to get rid of that hissing sound hmmm....

Since they think it's so easy to put the car into limp mode, when you pick the car up tomorrow, ask them to demonstrate. If they can't, your case becomes stronger. If they can, then you now have reason to believe that it might explain your problem. Either way, you win.
If it has already happened to you more than once, you should demand they put the blackbox in now. They are essentially telling you, "prove to us that it's not your fault by having it happen again." You should put it back on them and have them prove to you that it's not the cars fault by installing the blackbox now.