I'm also considering a Stillen. What are the differances between Gen I vs Gen II. If I buy new now, is only Gen II available?

 

Sorry I haven't gotten the info up yet but Josh summed it up pretty well. I will get the second graph up tonight but as was mentioned before the numbers weren't impressive and I can't really explain it. When I first put the exhaust on, I swear I could feel the car run stronger.

Yes, this was a dynojet. I am waiting for the shop to email both of the files to me. Unfortunately, they may have "lost" the first set of files.

One other problem to note, the resonators on the exhaust started bumping against the bracket that prevents the driveshaft from falling if the driveshaft breaks. On Sunday, I got under the car and did some adjusting. The resonator is still pretty close to the bracket but the banging has stopped. We will see for how long. I went ahead and bent the bracket a bit to allow for more clearance. In addition, I put two washers between the rubber hangers and frame to help with the clearance issue.

To sum things up, I am pretty disappointed in the numbers but I do plan on waiting a few weeks and trying again to see if it was some sort of anomoly. I am also pretty disappointed in the fact that the exhaust fitment was not perfect. I do still have some concerns that the banging will return because there is not that much clearance (about a finger's width).

Frustrating.

 

Sorry to hear about your dissapointment bro. I've heard similar stories that the catback does not yield the HP Stillen claims. On the fitment issue, this is the first time I hear about it. Everyone seems to think it is perfect. Maybe you should call Stillen and tell them about it. I had clearance issues with the coupe midpipe when I had it, but I bent the pipe instead of the bracket. I don't like changing anything on the car for an aftermarket part. Good luck and hope you get the numbers you expect.

 

Chico,

I wasn't expecting the 20hp Stillen claims but I did expect 6-10hp based on a bunch of other information I have seen. I am going to call Stillen and see what they have to say about the fitment. You are right, I have never heard of anyone having a problem with fitment so I did not expect any issues.

As far as bending the bracket, I am not that concerned about it, the bracket is easily removed via 4 nuts and can be replaced easily with a new one if necessary.

 

maybe the reason you are not seeing the gains is b/c of the fitment problem and you have a leak somewhere? i hope you get it resolved soon. let us know what stillen has to say to you...

damn i'm disappointed too, i was expecting more from that exhaust

 

It did not sound like it was leaking at all, but it may be worth checking out. I think Jamey's expectation of 8 HP (he mentioned this number before the dyno), was pretty reasonable.

As mentioned this was a dynojet, and I am still waiting for my results to be emailed also, so my guess is they have not got around to it.

I kind of agree about the corrected vs. the uncorrected numbers, but some people believe that there is too much that can be altered with corrected numbers depending on conditions. If you look at how the numbers are actaully altered for corrected there is some room for error. I say if the conditions are close (we were inside and other than a slight increase in humididty and a slight drop in temp, the boro and other factors were all very close) go with uncorrected.

 

Original post updated with second dyno chart.

 

Which chart is which?
(edit: stupid response)

 

So, looking at the 2 graphs they did use STD correction. They used 1.04 for the first run (left) and 1.01 on the second run (right). It looks like it was about 12 degrees higher and other factors were pretty close.

I am not sure why when I asked the shop if they were using corrections they said no....

 

For everyone interested, here is an update. I have played around with this thing and adjusted, shimmed, banged, etc. on everything I could think of to make it fit properly. As a last resort, I took it to a couple of exhaust/performance shops and they played around with it, however, in the end the banging always came back after about 50 miles or so. The exhaust always seems to revert to its "sweet spot" which is too close to the car.

I called Stillen and they swear they have never heard of any fitment issues with the exhaust (and in their defense neither have I). The exhaust warranty, however, does not cover fitment because according to Stillen it fits.

The problem lies in the X-pipe I believe. As far as I can tell, it comes off the cats and angles up toward the bottom of the car rather than angling down or running parallel (and no you can't put it on upside down as someone at Stillen suggested I did because of the way the bolts come out of the cats). As a result, the resonators bang on the bracket under the drive shaft (there is less than a finger's width of clearance between the resonator and the bracket). In addition, after one particular adjustment part of the X-pipe actually banged against the bottom of the car frame. There is only about a pinky's width of clearance here as well. I think it is a matter of time before the torque of the engine causes this to hit again.

As a result of all of this, the exhaust is now sitting on my garage floor pissing me off. I really miss the sound but I could not enjoy my car with the exhaust on. I haven't really decided what I am going to do. I am sure that I can take it to an exhaust shop and they could bend/weld/whatever it to make it work, however, I really do not want to put any more money into this thing (especially if I am not getting substantial performance gains).

 

I have it on my 05 Sedan without a single problem and mine is the gen 1 catback for the 03-04 models. Like we have said in the past, its not the exhaust.

 

What then would you suggest is the problem? I can see where the exhaust has bumped against the car (it has rubbed off paint both where it was hitting the body and the bracket below the drive shaft). When I checked for clearance I had about a tight pinky's width in these two spots.

I have completely reinstalled the exhaust numerous times (both on my own and by a shop that has installed mulitiple Stillens on coupes). The install is pretty simple I do not think there was anyway I or the shop could have botched it. All bolts were torqued to factory specs when I personally did the install (except the clamps which were tightened without using a torque wrench). I did not over tighten the clamps for fear of not being able to remove the exhaust if I ever wanted to sell the car, however, they were most definitely snug enough to prevent any movement. When the shop did the install, they tightened everything tighter than factory specs (including the clamps) while shimming the exhaust in hopes of eliminating the problem. It did for a while but after a few days it was back to the bumping.

Anyway, I either have a one-of-a-kind exhaust or a one-of-a-kind sedan because the thing just doesn't work. Once the exhaust was removed from my car, the problem was solved.

If anyone else wants to try it on their car, come pick it up.

 

Well put everything together. No one else is having a problem except you. Your ypipe looked slanted which indicates either your engine mounts (one might be broken or not right) but I doubt its the exhaust.

Take a look at all my pics here and compare them to yours....

http://www.sah2o.com/russ/stillenexhaust1/part2/

Damn and I was just in Dallas!! Wish I knew about this or I would have stopped to compare yours with mine.

 

After taking a look at all of your pics it is hard to compare because the x-pipes are completely different. On the Gen II, the x-pipe is much longer. See JBX's pic below, I have circled the areas on my exhaust where I have the least clearance. These are the areas that bang or make contact (based on the fact that paint has been rubbed off the bottom of the car and where there is the least clearance).

The x-pipe hit the bottom of the car near the bends (not consistently just twice but I could really feel when this was happening because the whole car shook and it scared the crap out of me), the resonators bumped on the bracket below the driveshaft (this was more of a thud that I felt up through the center console armrest and once it started it happened each time I hit a bump).

Just in front of where the x-pipe bends there was only a finger widths clearance between the pipe and the car. I can't take the chance of the x-pipe hitting again because it was so violent this surely would have eventually caused some other damage to the car.

On your motor mount theory, I would hope that's not it seeing as how the car is only 6 months old. Is there some way I could check that myself? Wouldn't there be other symptoms of this separate from the exhaust? Sounds like this would have to cause other problems. I am open to any possibility.

 

Well, you can do this but be careful. Have someone in the car and have the parking brake up and the cars wheels up against something solid. And start to release the clutch to force the engine to flex which will cause the exhaust to flex as well. See if it flexes a lot. Really you can only tell if the mounts are bad by clunking or visually looking at them.