Dyno Results 987.2 Plenum and TB

My car is a 2011 Black Cayman S six-speed with 26K miles that I bought about two years ago. It was bone stock at purchase and since then I have added the following: OEM short shifter GT3 brake master cylinder and brake ducts Stainless steel brake lines Slotted rotors and PFC 08 pads 19" HRE wheels for the street and 18" Apex wheels with NT01's for the track Apple car play Pioneer head unit JRZ RS2 adjustable coilovers Tarret mono-ball strut mounts FVD Brombacher race headers and software tune ...and finally an IPD competition plenum and GT3 throttle body . FVD states on their web site that adding a plenum and throttle won't add much power unless exhaust headers are upgraded first along with a proper engine map for the intake parts as well. I wanted to know how much performance (or lack thereof) I was getting by adding the plenum and TB so I took the car to Dyno-Comp in Scottsdale. Using a dyno dynamics dynamometer they did a baseline run with the headers and FVD tune (green line) showing 306.9 peak HP and 252.4 foot pounds of torque. They installed the plenum, throttle-body, and uploaded the FVD map for all of my performance parts. The after results (red line) showed a gain of 10 peak HP and 21 foot pounds of torque. The torque increase is the most noticeable improvement throughout the power band and made a big difference especially in the mid range RPMs. So far the car runs great, no CELs, and is much faster than stock.

ZD, Impressive! Are those engine or wheel numbers? Joe Henley

Those numbers are at the wheels. The tech who worked on it estimated crank horsepower to be between 375-380.

Nice juicy midrange bump for spirited street driving

Thanks for sharing this. Good to see that increase is not mostly at the high range and that there is no low end loss.

Those are impressive results, they seem to end the controversy about whether these mods deliver.

The difference over stock is substantial and completely transformed the vehicle. I was hesitant to add the plenum and TB after reading the conflicting posts others have shared. I had a different brand of headers and tune previously that I ended up removing because of multiple CEL problems. After speaking with Rhonda at FVD she assured me that they did not have CEL problems and that their maps worked seamlessly with headers and other performance parts. She also advised me that adding a plenum and TB without opening up the exhaust first and updating the engine management software accordingly would yield poor results. Hopefully this helps other people considering whether or not to add the same modifications. They do work when done properly and I would highly recommend FVD for performance upgrades with their progressive tuning program. My car now posts power numbers equivalent to the 997 Carrera S but with the mid engine balance and slightly lower weight. Combined with the JRZ suspension, brake upgrades, and nitto tires it is a very well sorted vehicle that can hold its own at the track and then with a quick swap of wheels and brake pads is still comfortable for street driving.

is this .2 specific or can we expect similar results with a .1 too? I heard .2 respond better to tuning in general?

I can't speak to performance gains on gen one cars. My car is a gen two DFI engine Cayman with all catalytic converters housed in the factory exhaust manifolds which is why race headers make such a big improvement. I still have the factory mufflers since they don't restrict airflow and I don't want any drone. First generation cars would presumably need to replace the stock exhaust manifold and mufflers to see similar performance gains. Rhonda with FVD owned and modified a first generation Boxster and could provide some first hand experience.

Yep, .1 cars yield gains by upgrading their stock exhaust to a high-flow system whereby eliminating the secondary (and utterly useless) cats.

I don't have dyno results, but have .1 3.4L with plenum, GT3 tb, intake and softronic 93 octane file and the grunt down low is night and day over bone stock All the sellers of product will find some way of downplaying/smacktalking the competition offerings. Like the OP, I did my own research and picked my path. The stock form was still fun.... but with the upgrades, the car actually surprises me. [emoji594][emoji100] Sent from my SM-G960W using Tapatalk

Yeah, each car and approach yields its own result. My path was 2006 3.4L 23,000 miles when i started (now 36,000). On stock exhaust I added plenum & GT3 TB, and FVD Brombacher tune. It was nice, but not life changing. I asked the engineers to include the same sort of throttle mapping that the Sprint Booster did, so I removed the Sprint Booster . After another year or so, i got a good deal on FVD Brombacher Sound cat-back system including their 200 cell high flow secondary cats. I still have the OEM headers and primary cats, and I added Fabspeed 's carbon-trimmed X-pipe. Sound is much richer and performance seems a bit snappier. I would guess that if I went to a long tube header setup, it would uncork the system. But, I like the balanced sound profile, now. I don't want to sound like a street racer WRX or fart-can Civic Si. Therefore, I feel like I have about the performance I can live with while not making things worse for myself, either. This week, I took the car for the longest drive that I have taken since moving from 5500 feet of elevation to 700 feet. I did a five hour drive down the Columbia Gorge through wildfire ash and smoke. I was able to execute some passes that took me to 95 or so. I think that the ECU finally adapted to the elevation with WFO throttle, that I just didn't get driving around town. By the time I got home, the car felt stronger. This is also after recently adding new Bosch plugs and "performance" coil packs, on 93RON fuel.

Fear not. Porsche's engine configuration won't allow this to happen. Going with a long tube header setup will only increase volume, not transform the sound profile that a 17 year old would think is dope.

I looked at FVD before I chose Soul long tube race headers for my 3.4 M97 engine . Scott at Softronics provided the throttle body/plumen race setup and mapping upgrades as well. This provided much improved mid range torque that without the headers , was not very useful. As Scott told me the 78 MM GT3 throttle body was all I needed as we have a hard stop at 7000 due to weak rod bolts. So no need for a 82 mm throttle body currently used by 987.2 's mods in the 9A1 engine which capture some additional HP above 7000. At any rate for those looking for a great setup for a 987.1 S, talk to John at Soul and Scott at Softronics. They are great to work with. I use a Milltek exhaust and pipe tips that works very well with the Soul catless race headers without drone or raspy exhaust sounds.

When you did the mods above was your car all OEM? Or did you have other mods already done? I’m looking at adding the IPD Plenum and GT3 throttle body to my 987.2 Boxster S OEM car. I’ve heard there is a slight increase in induction noise. I’ve got military service related ringing in my ears (tinnitus) and am concerned that the increased intake sound might be too much for me to tolerate. I’ve got another Porsche that has the Porsche Sport Exhaust and even engaging that makes the tinnitus intolerable. I have to drive with it off.