I am looking to order a 991 CS later this year and would like to get some feedbacks on whether I should check the 'PowerKit' box. I know this topic has been discussed many times but I cannot find any references to the performance difference between the Non-X51 vs X51 C2S.

From what I can find on the forum, it basically summarizes to 30 more HP and 0.1 sec faster for 0-60. I am more a 1/4 mile person so would like to know what is the difference in 1/4 mile. Magazine results are not very reliable. I saw Motor Trend had C2S at 12 sec flat (non-X51) and Autolog had C2S (with X51) at 12.2 sec. Does it mean we won't see a difference until we go above 100+ mph. I will rev the car to 7500 rpm regularly but I won't hit 100+ mph everyday.

I think the X51 is actual a deal because it is really $12K-13K since the package includes sport chrono and PSE. Any real world experience will be greatly appreciated.

 

I love having it. You'd be better deciding right from that start that you aren't going to get it. I think if you are already considering it, you will always be wondering what your car would be like without it. The thing that pushed me over the edge was seeing several guys that added after the fact.

If you haven't seen this, I'd read it.

 

I'd wait to find out about the GTS that should be available in the 2015 model year by the end of this current year. It should have this included with some other tuned up goodies bundled up with it. The GTS should be a hot car! That's what I've heard anyway!

 

13 grand for .1 sec improvement. That's a no brainer. If 13 grand means nothing to you, then go for it.

 

You might want to search on X-51.. I think you are likely to get a variety of opinions and many of those fairly passionate both ways.

Most of the folks I believe who have it, seem to think it was worth it. And lots of debates as to if the 13K is worth the advertised 30HP. Actually I think you get SC, so its more like 10K or so.

Although I've read some who claim they can definitely tell even as a DD, my own experience test driving one was that as a DD I couldn't tell any real difference. I don't get that there is a huge torque boost hence the relatively small increase in 0-60 performance. So maybe you see it more in acceleration at the upper end...

Personally, it wasn't dramatic enough for my DD (although at times a bit aggressive) driving to be worth the extra so debated it and passed on it.. No way I'd ever do it as a retrofit as I hate the thought of tearing the car apart. but that's me..

It seems, and I'm pretty agnostic on the issue.. my observation is that the folks who place a lot of importance on HP specs seem to be the most vocal in their opinions about the 911's being "underpowered" seem to value it the most.

I certainly wouldn't mind having a few extra HP, but I'm in the camp that believes a C2S already has plenty of HP for most driving situations if you drive it right (hi RPM vs low RPM V8s). Some how in real life you can do < 4 sec 0 to 60... (yep it's 4.1 in the specs but that's conservative) and hit 179 mph..

And it's torque that gets you acceleration in that 0 to 60 number and C2S seem to do pretty well against the V8's in that regard.. But it seems to be more a matter of perception than reality... Although it is impossible to argue the point to those who believe otherwise..

Like I said, I'd take the extra 30 HP, but I decided to spend the extra 10K on creature comforts I use every day.. And as DD non-track guy.. I find I have plenty to get my self in a heap of trouble already. God help me if I were to get a turbo..

 

Quarter mile differences are small and as irrelevant as comparisons in car mags, given all the factors that impact test times collected at different times and places. Find a car with it and see if you like the increased zing from about 5k rpm to redline- from any speed in any gear- enough to pay for it. It is quite real, obvious and easy to assess.

 

Depends on where and what you're coming from and where you plan to go.
But you certainly won't find a definitive answer here.

 

I considered a car with it when I purchased but ultimately passed. I think it's a money sink since you won't get the 13k back when you sell it. You might get a few k but that's about it.

Disclaimer: I rarely keep a car longer than 1-2 years.

 

The GT3 is the better value car when you can drive it. Not much more after adding the PowerKit to the base S.

 

The main difference in power is above 6500 rpms per the graph on the attached. Most people don't spend much time in that region, especially after 2nd gear. Under 6500 rpms I doubt you'd notice any difference, except that the torque curve is flatter, so no midrange surge typical of a flat 6. .

No doubt this option was made for the autobahn where you do drive at high rpms and spend a lot more time in the upper power band beyond 2nd gear to get up and over triple digits with authority. If you never see triple digit speeds, I see this as useless other than bragging rights (which is useless too).

If I still lived in Germany, I may want it. Here, it's overkill.

 

Its simple of you have x51 then we recommend it if you don't well I guess it isn't worth it. Typical...

The reality is that the x51 is a better engine built for higher performance and is as close to a gt3 as you can get. It is built on a separate assembly line for a reason.

I have no proof but I believe the power to be under rated which is typical of porsche. Heck Fabspeed claims 40+ hp with bolt on exhaust.

Don't forget all of the extras you get with the x51 which makes the price more palatable.

 

Wait for the GTS!! I am.

 

Yup waiting is fun... perhaps the gts will be worth it if in fact it is available this year. It's all speculation right now.

 

I have more faith in a GTS for this year, than 40 hp from an exhaust.

There will be a 911 and Cayman GTS in 2015.

The power kit is nice if you can swing it. Go for it!

 

I'd better buy this
0.0 sec improvement for 0.27 grand.

http://www.suncoastparts.com/product...or_Accessories