Thanks... This was a tremendous help. Pass side top bolt came out fine. Drivers side snapped, but at least it is off! Here are some pics that also may assist.

I will eventually figure out how to get pics to upload properly!

Hope this helps. I am new so if this is worthy of some rep dont hesitate. :)

Happy Z motoring!

They made it look so easy. I don't have all those tools. I'll probably have to find a shop to do it.

Footloose, I just put my cats, magnflow exhaust and sway bars on over the weekend. Total time was about 8 hours, including stopping to take pictures. You could probably do the Cats in 3 hours even if you have not done any work before.
Really not many tools are needed... Hit the nuts with PB Blast the night before and you can get it done.. I was able to do it pretty easily with a jack, jack stands, a ratchet and extensions, a box end wrench, and a adjustable wrench(for the oxygen sensor). If it isnt your daily driver you will be fine even if you get in a bind.

that was absolutely the worst expieriance in my life. everything that could have went wrong did. snapped bolts, stripped bolts, i even stripped the threads on the headers when i was taking the bolts out. i think i have an exhaust leak on the drivers side where the top bolt is. i tightened it but after i tightened it it stripped somehow and i cant get the bolt out to put a new one in. i dont think its bad though, if u put ur hand where that bolt is u can feel air if u hit the gas but u cant feel it if its at idol. it doesnt sound like theres a leak though. i would definately pay to have this done if i had to do it again haha. on a positive note i dont have a CEL though. also i dont know if anybody mentioned this but if u strip the stock bolts when taking them out of the header u can use a star bit socket to get them out. that what i had to do.


http://socialcam.com/v/lLsETdD4

Me and the boys just finished installing GTM Resonated Test Pipes and it went really well. It took about 2-2.5hrs in total. I went to Harbor Freight to buy all the stuff I needed. Started using 1/2" everything and the hardest bolt was on the drivers side towards the middle of the car. Our sockets didn't really fit in there too well and tried some 3/8" and broke the 3/8" universal joint in pieces so eventually after some work we were about to get the 1/2" stuff in there to get it. It was actually a lot easier than people make it out to be. I sprayed the "demon" bolt with PB Blaster, waited 10min and then moved without issues, and then they stopped about half way thru and then snapped. No biggie though.

The hiss from the VQ37 is rather annoying but all-in-all it was worth the upgrade. I can definitely feel the extra power and sounds a lot deeper and a bit louder too, which is nice since my HKS Hi Power Ti is rather quiet.

Just installed the berk hfcs and couldnt be happier. Install went smoothly and only snapped one bolt. The sound is beautiful and not raspy at all. Definitely more throaty and the car already feels like its breathing significantly better. Overall a great mod at a great price.

One thing that does concern me though is at start up it is CRAZY loud! To the point where the interior panels shake and almost forces me to shut off the engine. Any ideas?? Goes away after 2-3 minutes and sounds normal after that. Only at start up. Smells like its slightly burning too. Any advice is appreciated.

Has anyone done this on a lift? I spent 45 min with different extensions and a u joint and I couldn't even seat the socket on the front bolt. Can I do it from underneath with a lift?

You get at the front bolts as stated from the engine bay. You may need to move around the intakes to get to it.

Tried that... for some reason I just couldn't get to it.

I performed this install on my old 350 and I had to use two 12" extensions and a 6" extension. A good flashlight is your friend. Having a light under the car helps too. It's possible, but a real PITA.

It didn't matter for me though because I ended up having two stuck bolts, one on each cat. So I drove to the nearest repair shop and had them loosen them. Imagine the sound coming out of my Z with the cats held on only by one bolt and the studs on the exhaust. Deafening!

I got it done... like an idiot I thought the back of one of the studs had a nut on it and that is what I was supposed to get... it screwed me up that it had two studs and one bolt...

The bolts were def the worst part but a breaker bar and a smashed finger was ultimately the trick (careful those bolts just let go all of a sudden). Best part was that with teh injens I didn't need to remove/move anything... my bay needs a super bath though after all that PB blaster.

Mission accomplished! But yahh^^ those bolts just all of a sudden snap loose, i thought i snapped the head off one because it actually sparked when it broke free...

I didn't even attempt to remove them safely. I purposely snapped the heads right off of them. It made things so much easier. Just use a breaker bar and throw some torque into it and BAM! On to the next one :tup:

How are you able to get the HFC off without having to go to engine bay?
I don't quite understand how. Could you please explain more clearly. Am very interested as I will be doing my installation soon as well.

He was saying he just got the rear two without going into the bay... the last one on each side needs to be accessed from the front.

Stupid bolt stripped on me.

+1... anyone?

Yes, that's what's I had to do. It takes 2 minutes to remove the upper portion of the Stillen Gen3 intake.

:iagree:

rep + 1 for you bro

+ 1 for you too bro

How do I go about removing the studs from the headers that were used for the stock cats? There's one on each side and its the last part for me. Im just a tad new at this. Any help is much appreciated :)

You don't need to remove the studs from the headers.

Figured it out after a couple minutes of looking at it and noticing the lack of 2 extra bolts that werent provided with the berk hfc's

great diy! this should def help when I put on my hfcs this weekend. :tup:

I just attempted to put in my Fast Intention HFCs this past Saturday, I had everything going well until we tried to attack the demon bolts, we ultimately couldnt get it, but Im gonna give it another go this week.

We gave it a go about a week later, we ended up cutting the passenger side OEM cat off, and we got extremely luck on the driver's side, as the bolt snapped off. *HUGE* sigh of relief.

Now Im just working on clearing the CEL/SES codes, as during the process, we ended up messing up the passenger side o2 sensor on the exhaust manifold. :facepalm:

I'm going to finally throw my ART pipes on later this week using this DIY. I had HFC put on previously when my exhaust was installed so I wont have to deal with the demon bolts. Now I need to raid the hardware store for some extensions.

Excellent write-up. Did this install today with a pair of Stillen HFCs and everything went nice and smooth (minus a couple hour battle with the dreaded evil bolts on the upper flange). Thanks for the info here. +1 rep from me. :tup:

How worried should I be about breaking the O2 sensor? Gonna be installing ART pipes in a few weeks and I'd hate to have to spend hundreds of bucks more if I break them.

You should definitely be able to do this install without breaking the 02 snesor dude. with the proper wrench..if you don't have one..buy one from advance auto, use it, then return it the next day haha.

excellent write up. I chose to have them installed by a nissan tech but this write up is SPOT ON from what I've researched over the last few months.

i wouldn't be worried

Just dont use any impact tools.:tup:

Excellent write up. I must admit I was a little concerned at first with how tough the Demon bolts were going to be, but everything went pretty smooth. I was installing Motordyne ART pipes coupled with a Berk CBE. I started out by running the car for about 5 min. and then spraying down all of the bolts with Kroil, starting with the demon bolts. From there I started breaking loose all the bolts from the cats back allowing soaking time for the demon bolts. Used open end wrench for O2 sensor. No need for O2 socket. Using a long handled 1/2 wratchet with impact sockets made this job a lot easier. When it came to the demon bolts I used a 24" impact extension, 12" impact extension and swivel socket. Used the handle from my floor jack as my breaker bar and the dreaded demon bolts were a piece of cake. No broken or snapped tools. :tup:

Special thanks to Fred Beans Nissan for great pricing, Tony at Motordyne and my 8 yr old son who stayed up until midnight (way past his bedtime) to help me. He couldn't wait to go for a late night test drive :happydance:

Man, thats awesome.

I used this guide to install my Berk HFCs earlier this year and it was a great help. I sprayed down the bolts with WD-40, went out to eat lunch with buddy in his STi, came back and sprayed it down again. Ran into 2 demon bolts (1 each). We ended up snapping the bolts at the midpoint but at least it came off.

Just remember not to rush the process. Be patient as much as you can because it will only get worse if you're not. Make sure the wrench and socket are flush with the bolt and not at angle before you apply pressure to loosen the bolt. It's tough to do this since the engine is in the way lol. My friend would lower the extended wrench down and I would go under the car and guide the socket onto the bolt to make it's flush before he starts to apply pressure. Just my 2 cents. Good luck everyone. Be PATIENT!

Installed my Berk HFC yesterday in my garage with the Z up on ramps and jack stands. It took about 6 hours, but I took my time... PB blaster soak, lunch and the demon bolt. The passenger side demon stripped but using a bolt extractor saved me. Some people had questions about the bottom 2 of the 3 bolts going to the headers. They look tough to get to at first but you can access them from below, the wheel well to the side and you can fish a wrench past the bolts and come down from the top (this is handy installing the new bolts because you need to hold the opposing nut/bolt as they both want to turn as opposed to the stock studs. The offset on some box wrenches just get you there.
The only problem I had that wasn't mentioned here was that Berk tossed in a standard/course thread bolt in the bag... I snugged down that one bolt and went to release the wrench holding the other side and noticed the bolt was very loose. Backed it out and looked at it and sure enough, the nut would only go on 2/3 of the length of the nut because of the wrong thread. I just replaced it with another. No knock on Berk because the quality of the cats... Weld and fit are excellent. The nuts and bolt guy was just having a bad day. Oh, final thought, I received both sets of gaskets (front and back). I have seen other post saying only front or pictures showing only front. Happy with the results.

Now that's what I call going bat$hit crazy with an uncooperative car part. My friend, you rock!

What about applying anti sieze goop in the event you need to remove stuff down the road?
Recommended or not necessary?

This help thanks just use a 1/2 ratchet better.