Modified headers vs aftermarket

I have a 2010 987.2 2.9l. It has 4 x 400 cell cats ( 2 in each manifold) I was thinking of removing the secondary cells after the O2 sensors which would leave just one 400 cell cat in each manifold. The question is how much improvement will I see for a free upgrade vs installing an aftermarkel header with 200 cell cats for $$$ I will also be installing a Borla cat back that I have

Define improvement. Are you looking for more exhaust note, power or both? If you think of the engine as an air pump for a moment you can picture how flow out would be less restrictive, and therefore a small gain. But chasing performance is a balance game. Ideally you want to improve the intake and exhaust commensurately, then one might look at the various tuning software offerings to complement a freer breathing engine. If you're seeking a shove in the back improvement, you're likely to be disappointed, if you're looking to have fun, feel like a personal custom tuner and that's part of your Porsche ownership joy, you're all good. PS Exhaust changes can yield CEL dash warnings. IMO, the headers and sport cats will yield more than simply removing one cat.

The stock exhaust isn't that restrictive on these cars. Even going catless long tube headers and a better catback will get you less than 10HP to the wheels. Its not much of a difference.

I haven't seen the inside of 987.2 mufflers but for reference, here's a photo of a 987.1 muffler I've cut open (prepping for DIY "Carnewal" mod) and also 987.1 Boxster headers and Cayman headers (no idea why they are different). Interestingly I've only just realized there's a bung in my headers positioned before the cat, Think I'll stick a borescope in there this weekend and inspect the condition of the cat, the car has done nearly 150k miles now. I'll also have a look at what the 3 into 1 merge is like.

I would think that my Soul long tube race catless headers and a Milltec muffler is more like 15 HP. The Softronic flash, race 78 mm throttle body and Plenum certainly pulls it all together nicely. I would guesstimate is about 308HP @ 6700 rpm at the wheels. I did this to improve the flat spot in torque around 4500, which it certainly did. I have had no problems with this system in 4 years of use.

I used these mods/parts to improve the cars performance, which they do. So, I really don't want to get my money back from others, just to be competitive in my use of the car. Its just like why I would spend money on Bridgestone RE71RS for 90% street use and 10% track. These tires are worth the extra money to me vs other summer tires. The TireRack's white papers confirms the performance these tires vs 3 other summer tires with useage on a BRZ. Close is the A052, but their wear is much higher. Some 987,2 S owners mimic the R build and with careful purchase, they do have good resale value.

I have a 981 base and run into this debate with myself all the time. My logical brain/gut tells me the price for the performance is not worth it for a street driven car (no track). But my diseased mod brain constantly thinks about it and would love to do it. I have the cash, just can’t seem to pull the trigger. Still looking for used 200 cell headers to save some money, they are tough to find. For now I am just gonna enjoy the car.

The .2’s have better resale value for various reasons. I’d say confidently it’s the best Cayman S beside the GT4 or R. The R isn’t worth the cash, but it’s a great car. My headers/exhaust, I got about 20hp gain and that’s with a Malone ecu reflash. They don’t leave a lot on the table for improvement… the only real way on an N/A car is displacement… but unless you need a motor it’s also not worth it.. your best value on these cars for mods is suspension, wheels and tires… even if it’s just springs which isn’t the best option but for 300-400 it’s the most cost effective mod for the money you can do

Ernest, If you have the money, then sky is the limit. You certainly can install the long tube catted headers and even a Softronic ECU flash, Thats about it for the engine. The suspension can be modified with either a X-71 group that includes swaybars and springs. The other way to go would be adding Ohlin R&T coilovers. The ride is just a little stiffer due to higher spring rates, but they differently improve turn in and weight transfer across the car. The final part would be Tarett GT adjustable sway bars. Then get yourself a set of wide lightweight forged wheels. Many Cayman owners go for 19 " because they fill the wheel well a little better than 18". I perfer the 18", 9" in f and 10" in the rear. Currently using Bridgestone summer performance tires RE71RS in 255/35/18 f and 275/35/18 r size. I lowered the coilovers to about 15 mm lower than OEM. No real downside to this setup except for speed bumps. In canyon driving, this suspension really comes alive.

dibehrns, I use my car mostly for the street and now just a few autocross. The exhaust does have a smell on startup but not when under any load. I use engine braking a lot, but the exhaust is not appearant. I keep the rear deck/window lid closed though so who knows about the actual smell. My wife does suggest on startup there is some smell. Again, this header system gives more power than the cated Soul system. I use a cloth to clean my Milltek exhaust tips. Not much on the cloth with a slight abrasive cleaner, (head light film cleaner). My car does not burn oil as I do not add oil during 4k fill intervals, so some of the exhaust gas residue would be on the tips.

For reference I installed long-tube decat headers in my 2.9L 987.2 Cayman, as well as Cayman R mufflers (I think they are the same as stock mufflers), and got a nice sound out of it but my butt dyno said no real difference. Maybe I should try some intake or soft tune. Thanks for the cut away on the muffler - I bet cutting the pipe leading into the CAT would do as much as any aftermarket muffler, removing any weight in the muffler will probably improve performance more than the improved breathing.

I run headers and muffler without cats. The car sounds mean and has really come alive. Now, I have also improved the intake side with IPD, GT3 goodies along with a tune. These cars came corked from the factory because the little ol' Cayman cannot out perform the 911. If you have the coin I highly recommend opening the car up to see the full potential. FYI. The picture above by Apexhunter doesn't show the smaller cat that is in the factory muffler.

I have the same and wholeheartedly agree. Sent from my iPhone using Tapatalk

Throw an underdrive pulley and a lightened flywheel and really let her rip! Suspension improvements a must to handle all this wicked horsepower.

I agree that when these parts are installed the seat of the pants issue is noticeable. But it wears off soon. After 5 years, 4 with long tube catless headers and Softronics Race Kit, which includes at early GT3 78 mm throttle body and a custom flash. Scott/Softroncis pair the wave pulses from the induction system to the Milltec exhaust muffler and twin tips through the ECU maps. EVOMS V flow induction system as well. This all sounds good, maybe 13-15 hp for a total of around 308-310 hp. The whole feeling is that these mods create a smooth delivery and the thrust is linear starting around 2500. This means that I do not need to wind out the engine into the 6 range to get really good boost on the street. My reason for the mods was to improve my mid range torque out of the corners in autocross. I also added a Wavetrac LSD to capture as much torque without wheel spin using as much throttle as possible. Many times slamming the throttle down like a sprint booster would do as early as possible. No wicked HP here, just manageable Porsche power. Edit= Installed the Sprint Booster, and guess what, I find that the race mode really does work well for throttle modulation mid corner and blipping the throttle in downshifting or engine braking. I like it even in free way traffic, rather than downshifting to catch the spot, I can just give it some gas and that throttle body butterfly is wide open. I don't think the 82mm throttle body would work as well on the M-97 engine with a cutoff of 7000 rpm. With the Wavetrac LSD, the Sprint Booster race mode modulation is instantaneous so I wear a soft sole loafer shoe. Getting the ball of my foot as close to the pedal as possible so I feel very connected. It's a great addition that leads to more fun run time. I'm pretty sure I will use the street (green) setting with wet weather, Currently i'm using my 18"OEM wheels and Michelin SP4's due to the 40 degree temperature use restriction on the RE71RS's.