Top Speed Bypass pipes initial impression

[dagdisco03]

Received mine quickly delivered on Saturday. Installed them by Saturday night and drove 100 miles Sunday. I see no issues with the over all fit. Bend to the factory U pipe to the muffler was off by half the tube width but nothing I couldn't just pull into place by hand. The pictures from the original poster are a full aftermarket system the factory CATs have heat shields and look nothing like what is pictured.

Nothing rubs and I'd say they follow the original path very closely.

The little adapter pipe I'm not sure about. It works but I wish it was all one pipe to the flange. I have a small leak on each side on that adapter pipe that I still need to mess with to seal up.

Overall for the price can't beat it tubing looks nice it was packed great.

For my car with 109K this helped out low end power all the way up to red line feel better. Throttle feels like it has better response. I felt my low end under 2K RPM feels better leaving from stopped. That surprised me I was expecting that I would lose power in the low end. I'm not sure if it has to do with the mileage and my old CATs?

Sound: Just enough for me very mild increase in sound I'd say it brings the exhaust sound up to even with the intake sound. I can hear the muffler now but just the slightest bit.

[shadrach74]

As it turns out I did receive 2 left [driver's] side pipes. Before I had verified that this was the case, Che, having read this thread, sent me an email with instruction if there was an issue. I called and they are shipping the correct pipe to my mechanic with a return shipping label for the duplicate left pipe. I'll report back as things move forward, but so far, Topspeed is doing everything they can to make things right.

[dagdisco03]

Here are a couple pictures before and after install. Hard to see much but figured I'd share since there is so much back and forth on what works. To install I only removed the 3 nuts on the flange, 2 nuts sliding coupler and 2 nuts on the hanger off the muffler. Repeat the same on each side of the car. I did not remove the muffler or anything else. I did remove the wheel for easier access to the flange nuts.

Stock

Stock

Top Speed

Top Speed

[Karl Nettgen]

I thought I should check my pipes before install after reading these posts and just found out I have two passenger side pipes.

[tony_fury]

How can a company that makes after market parts not pair the components in the boxes properly?
Seems they would have a slight amount a quality control before shipping something out the door..
puzzling...

[dagdisco03]

Good to hear Danger I was definitely expecting the placebo effect response. And I felt this livened up the bottom, mid and throttle response significantly. I was pleasantly surprised that's for sure. I was expecting more noise and slightly less power. More noise was quieter then I expected and power was butt dyno approved

[dagdisco03]

Thank god mine were right I didn't even check each side before the install. I pulled one from the box and said these look good I'm happy and started to pull the car apart. I would have found out the hard way after getting the second CAT out I unwrapped that pipe.

[2000boxster986]

I've heard of one exhaust leak with these at the small pipe connection. Anyone else experiencing this? I'll be installing these soon and am just curious if I should get some muffler paste to add to the joint. Thanks.

[delubozparts]

Originally Posted by Karl Nettgen

I thought I should check my pipes before install after reading these posts and just found out I have two passenger side pipes.

PM received, correct set replacement on the way along with FedEx return shipping Label. My apologies for our glitch on shipping dept.

[sgt brad]

well i received the second package yesterday, but won't get to open it until sometime this weekend or early next week. hopefully we have everything sorted out this time.

brad

[F1GP]

Finally got my pipes installed yesterday. Initial impression is the car sounds raspier and there's a slight increase in volume especially around 4000rpms and up.

It took 3.5hrs for my shop to do the install. It was longer than expected because they initially ran into some issues last week with rusted/fused bolts and then the discovery that I was shipped two left pipes. Yesterday they completed the installation but had some minor issues with the pipes lining up perfectly. They ended up trimming the pipes to fit properly.

Despite these issues, I'm pretty happy and the price can't be beat.

Two questions though...is it normal to have a burnt smell after the cat-bypass pipe install? Does this eventually go away?

[shadrach74]

Originally Posted by F1GP

Finally got my pipes installed yesterday. Initial impression is the car sounds raspier and there's a slight increase in volume especially around 4000rpms and up.

It took 3.5hrs for my shop to do the install. It was longer than expected because they initially ran into some issues last week with rusted/fused bolts and then the discovery that I was shipped two left pipes. Yesterday they completed the installation but had some minor issues with the pipes lining up perfectly. They ended up trimming the pipes to fit properly.

Despite these issues, I'm pretty happy and the price can't be beat.

Two questions though...is it normal to have a burnt smell after the cat-bypass pipe install? Does this eventually go away?

The smell is likely do to penetrant residue and residuals from the pipe mfg process. It should dissipate after a few heat cycles.

Glad to know it went well. Do you notice any difference in drive-ability, power. power curve...seat of the pants measurements?

[Johnny Danger]

Originally Posted by dagdisco03

Received mine quickly delivered on Saturday. Installed them by Saturday night and drove 100 miles Sunday. I see no issues with the over all fit. Bend to the factory U pipe to the muffler was off by half the tube width but nothing I couldn't just pull into place by hand. The pictures from the original poster are a full aftermarket system the factory CATs have heat shields and look nothing like what is pictured.

Nothing rubs and I'd say they follow the original path very closely.

The little adapter pipe I'm not sure about. It works but I wish it was all one pipe to the flange. I have a small leak on each side on that adapter pipe that I still need to mess with to seal up.

Overall for the price can't beat it tubing looks nice it was packed great.

For my car with 109K this helped out low end power all the way up to red line feel better. Throttle feels like it has better response. I felt my low end under 2K RPM feels better leaving from stopped. That surprised me I was expecting that I would lose power in the low end. I'm not sure if it has to do with the mileage and my old CATs?

Sound: Just enough for me very mild increase in sound I'd say it brings the exhaust sound up to even with the intake sound. I can hear the muffler now but just the slightest bit.

What you're experienced was correct. The secondary cats are extremely restrictive (400 to 600 cells depending if they share the same part as a 996). Therefore, by reducing a significant amount of back pressure, along with weight, your vehicle should have definitely felt more responsive.