That's cool to see. I would find it interesting to understand why a lot of people who do these mods are not impressed with the gains like me. I know plenty are but there is also plenty of threads about it saying it wasn't worth it.

I read a while ago that with our cars the gains can be felt in different areas such higher/lower rpms depending on mods which picking up the effect in higher rpms might be a little harder to feel vs down low.

 

WTF are you talking about?!
Here is how this played out:
Zach L: "Catless are good for about 25 whp and high flow sport headers are good for about 20 whp."
You: "25+20hp ? I have full system(equal length race headers, no cats, high flow muff's and crossover pipe.. with tune, filter, IPD, throttle body and even a jegs racing sticker(+7hp)... I don't feel anything like 45hp gain."
Me: "Reread what was written..."
Zach L: "It's either or. You can't have catless race headers and sport headers at the same time. Race headers (not cats) = ~25whp Sport headers (high-flow 200 cell cats) = ~20whp"
Me: "...covered in later posts..."

I had responded that the original post from Zach L didn't say what you thought it did. However, I had missed that he corrected your mistake after my original comment. Rather than repeat what was said, I edited my post to say it was addressed in later posts.

...and then you freak out over something I don't even understand. Obnoxious?! Attention *****?!
Yea "bud", I'm the problem here.

 

lol wow snowflake much if thats freaking out … you need some life experiences bro.

 

Probably because the power gains are small. Most of the exhaust companies quote like a 10whp gain from headers. The cost to benefit ratio of headers if you're looking for performance is poor. I think the 3.4 motors tend to see larger gains than the 2.7 or 2.9 as well, but I could be making that up. The dyno sheets or quoted numbers out there are almost always from an S so it's hard to tell.

 

Ya that’s probably pretty true. the 3.4 in my 911 seemed to respond a little better to the mods. This 2.7 in my cayman.. just dont feel it.

 

Wow, I thought I was on the 996/997 subforum after reading these defensive responses. We mid-engine owners should be held to a higher standard.... But yeah, bigger displacement is the key to power BIG gains here, not the combination of a dozen bolt-ons with a Softronic tune. Having said that, .1 cars have those pesky secondary cats in the catback exhaust so removing them should yield something, no?

 

There's so little to be gained to do mods like headers on a 2.9L...

 

ya i learned that after spending the money

 

I did the exhaust mods on my 2.9 for the sound, knowing any power gains would be minimal at best.

 

The 2.9 and 3.4 in the .2 use the same factory headers, as do the 2.7 and 3.4 in the .1 cars. That being the case, they would encumber flow on the larger engine more since they're even less efficient for an engine that size. On the smaller engines, the catless headers may only add 12-15whp.

The only 987 with unique factory headers is the 987.1 Boxster S 3.2L which features better flowing headers. They are an upgrade for a 987.1 3.4L car and will make additional power even with the restrictive OEM cats, about 5-6whp.

BTW, where'd the OP go? lol

 

I've been trying to find out if anyone has some definitive data on this, I picked up (super cheap from a local club member) a full Cayman 3.4 exhaust and noticed the difference between my 3.2 Boxster headers and the Cayman header. The Boxster header "looks" a better design but I couldn't think why they would put a less efficient one on the 3.4 engine...outside of cost factor (looks easier to manufacture). I thought there may have been some exhaust black magic going on. They are still in my basement and I was going to change to them due to much lower mileage (my BS now at 149k mls) and hopeful performance gain......but now maybe not..?
If you can point me towards further info I'd love to learn.
Or...anyone got a buddy with a Dyno in the Midwest and we can do a proper back to back test...?

Cayman header

3.2 Boxster header

 

The change to a less efficient log-style manifold for the 3.4L makes sense once you're familiar with the evolution of the M96/M97 engines and how the M97 3.4L in the 987.1 Cayman S was developed... It's based off the 3.4L M96 engine used in the 996 base Carrera. In that car it developed 296hp. But Porsche upgraded that engine for the Cayman S. They took that 3.4L M96 Carrera engine and added the cylinder heads from the 997 Carrera engine. The 3.4L Cayman S M97 engine used the same cylinder heads with more efficient VarioCam Plus valve timing as the 3.6 and 3.8 M97 engines used in 997 Carrera and Carrera S models. So the Cayman S should produce about 310-315hp by all rational estimates if one was looking at the various Porsche engines at the time and how much each was rated for power. But that would've put the Cayman S too close to the 911 base Carrera (325hp) for Porsche's comfort so they detuned it and made it less efficient and bottlenecked it using techniques such as the crappy log-style manifolds amongst others. Porsche wanted a difference between the Cayman S 3.4L and the Boxster S 3.2L, but not as much as to encroach on the 911.

 

^^ nice info! Tweaks here and there from the bean counters easily neutered the 3.4, Can't step on big brother's toes, right?
Luckily, if one's willing to spend the money, those lost ponies can "mostly" be recouped without even a full engine reconstruction....Your "log style" description is on point. Ask anyone and they'll tell you. That design is borderline brutal as it is ugly. A long tube design with nice a merger works wonders and that doesn't include a set of quality HFCs that incorporate a significant cell decrease.

A bit off subject regarding exhaust but still pertinent... The Cayman/Boxter intake runners are a huge bottleneck as per the most knowledgeable M9x guru in the business. We're being suffocated, especially those with even larger than 3.4 liters. A new design could be made but, it's just not worth it monetarily. The prices of 987s aren't escalating to the degree of 996/997s. Additionally, there's way fewer of us as potential buyers. Where Porsche gave us the superior driving dynamics, they boned us in the engine department.

 

I've posted that in other threads/forums... the intake manifold runners are a major bottleneck. Moreso than the intake, throttle body, and plenum, which everyone focuses on.

There are high-flow intake manifold runners available for 9A1-engined cars (9x7.2 and 9x1.1) for about $4,000 but I don't know of any being made for M96/M97 engines. Here's a comparison of the Dundon intake manifold runners from MotoiQ's 987.2 Cayman S build. Next to catless headers, these are the best way to make power from a naturally aspirated modern Porsche engine.

 

4k! Think I'd be considering ITB's for my non DFI M97 at that price point...yes it'd be more but that sound...