I completely agree with the above statements, especially comments about the 3-6k rpm range and the apparent lack of harshness above 6.5K. I can't explain that. Engine feels like it's running a lightened pulley or something now, weird. Just seems to rev more freely. VVEL FTW!

One other thing I immediately noticed. The mechanical sounds of the engine sound better, especially with a throttle blip from idle. Also weird, but I like it. And this I can explain...with a less restrictive exhaust, the loudest noise now comes from the tailpipes; with the OEM exhaust it seemed like the noise was emanating from the resonators, almost from underneath the vehicle. Less noise in the cabin when cruising!

I 100% agree with everything you just said. My car really came alive between 3 and 6K with a huge boost up top past that all the way to red line.

Its funny that you say the high RPM harshness is gone, I took my mom for a ride yesterday and was commenting to her that the engine is much smoother now up high. All in all this exhaust did wonders for my car. I'm very pleased with it! Good job Berk :tup:

Post-Berk Install dyno- with stock cats - 3pm today
 

I'll bring my DSLR for video :rock:

:happydance:^^

Breathing mods definitely help with the high rpm harshness.

No Soup For You!
 

Well, a tree took out the local dyno shop :ugh2:

Wow, talk about owned lol.

This whole area looks like a tornado came through

I saw some pictures, looked wicked...

:owned:

Anyone else on the group buy gonna do a dyno pull?

I'm sort of interested in doing one, even though I don't feel like driving to Atlanta. I didn't do one prior to installing the CBE/HFCs, so I'm not sure what good it would do the community.

Yeah having a baseline would help. Don't waste your time/money.

C'mon Berk group buy people. Y'all made enough noise in the last few weeks, step up and get er done.

Oops, missed this. Yes, I am. Putting my setup on today. When I'll get to dyno, not quite sure - fairly soon. Probably in a couple weeks.

I do have a baseline at a shop, but it will not be accurate.
It was done last year and in 90° weather, it is in the 60-70° currently.

I will probably be at a dyno day April 24, but until then I'm SOL on getting a dyno run in.

You have baseline numbers already? Say yes, lol.

I do. Unfortunately, I think the dyno got a terrible read so my graph is flawed :-p. But, it looked like I put down the normal 275ish that everyone else puts down on Dynojets.

It was my torque that was in question...

I swear, unless you go on a dyno, do a baseline, then furiously put on a modification, then run another dyno all in the same morning, you can't get a reliable read for gains.

Dyno's only measure torque, HP is calculated.

But basically you're saying that the middle of your graph is screwy and so you may have not got an accurate peak torque measurement?

Well, right. Basically everyone peaks HP somewhere around 7K and it levels off. Mine was supposedly at 7.5K and still rising, and I barely hit 275. Dynojet only registered 205ish torque or so. So, something didnt seem right. Never did get a response from Altered Atmosphere on this...

HP is calculated (continuously) as Torque * RPM / 5252.

So if your peak torque measurement is low then there should also be a dip in the HP curve between 4-5k rpm. The torque plot and HP plot always cross over at 5252 rpm provided they are plotted on the same scale.

Hey Dub,

Where's the dyno day?

Hey man, Its in Grand Junction, CO, from what I have been told. I will try to get some official details and let you know by pm man!

Anyone have a video with stock cats? Tracking number says Thursday but i'm dying to hear how it sounds.

well i'll be dynoing my car unfortunately it will be totally useless as it will be affected by the new intake flywheel testpipes, as wheel as all the other crap i have done.

So you don't have a base to go off of? Still would be nice to see what your Z puts out though! Awesome that you guys have access to Dyno's...We had a Dyno shop here a few years back...Unfortunately the owner of the Dyno shop passed away in a bad car crash ( R. I. P. Will), and no one ever picked up after it..

nah never got out and did a baseline it's looking like it'll be a while anyway still waiting on some parts for the rear end to arrive.

Forgot to ask this, what size resonators come in the Berk exhaust? Anyone measure or remember them posting this info?

Thanks.

Steve, do you have anything else besides the CBE? Like HFCs?

Nope that is with stock cats. The camera was only about 4 feet from the pipes. :icon17:

No idea Dreamer, but there are some good pics in the threads, you might be able to get a feel for the size.

It doesn't sound bad, but adding HFCs would give it a deeper tone.

no question about it. but what about volume? I'm pretty happy with the volume as it is.

You mean will HFCs increase the volume? Yeah, they would. Not a ton, mind you. But yeah it'd get a little louder.

I'll measure them when I get home tonight.

Thanks, I assume they are 18 or 12, but who knows.

They are 12 inch long on the widest part and 15 in total if you include the tapered ends. (I hope that makes sense...)

What I was looking for, so probably "12" by definition then, thank you.