[sweetsound]

Wondering if anyone has first hand experience with the Cobb or Techart tune offerings on a 718 S or GTS.

I'm considering these two options, but wonder about the HP increase claims, as well as (any) impact on driveability.

Lastly, (I doubt anyone has a comment on this as yet) - with 350HP+ already extracted from a 2.5L, how much stress can these 4 cyclinders handle without getting tired or heading for an early retirement?

Thanks!

 

[cbarra]

I have the same question, but I'm concerned about warranty issues with these tunes. I came from a tuned VW MK7 GTI that was a lot of fun and I never had any issues, but the turbo blew the very next day after I traded it in. Good timing! With this much invested in my 718 CS I hesitate to do any tuning/mods.

 

[timlaw]

I agree that I would not want to invalidate your warranty by extracting more power - after the warranty runs out then maybe - I guess a lot more will be known about these engines and a lot more tuners will be offering products once these cars are out of their warranties

there are some proper looking dyno vids on youtube showing the cayman S already puts out more like 400bhp at the crank so in a relatively light car does it need more power?

my CGTS seems plenty quick for me but I tend to leave my cars as they left the factory

 

[sweetsound]

I fully appreciate the concerns about warranty. However, my focus was on a 911 (essentially for the 2 reasons of power and engine/exhaust sound) but have decided I'm not willing to pay more for a flawed vehicle (and then they want you to pay for rear steering to help make up for it) . (gasp - I said something critical of a 911) I'm not looking to start a debate on that subject - just explaining my own personal thoughts.

If I can get some reliable information about tunes on the 718 then I could potentially solve for (my perceived) power deficiency and have 'the perfect car'. (except for the exhaust note).

 

[Semitone]

I could potentially solve for (my perceived) power deficiency and have 'the perfect car'. (except for the exhaust note).

That's interesting. I struggle to find much of a power deficiency in the 718 GTS vs. 911 range ( hort of the TT or GT cars). Sure there are cars like Corvettes and Mclarens with better 0-60 times, or even 30-60, but not sure what you are doing with your 718 that you have a power deficiency. IIRC, Car and Driver clocked the 0-60 at 3.6 secs for the S model.

There isn't even a perceptible turbo lag when the car is driven like it is suppose to be, IMO.

Sure, on a track with a long straight, you can always use more power but even there, I don't think the non-GT 911s are crazy faster. Marginal, if at all, for most models. Actually I haven't had the opportunity to get my car over 160mph so not sure even about stability at higher speeds vs 911.

None of this is meant to discourage you from modding your car any way you want and enjoying the **** out of it. Just a bit surprised at the term "deficiency".

 

[ZuffenHouseRules]

Ehresmann Automotive GmbH gets 450 crank hp on a 718S 2.5 with their Stage 2 (downpipe) tune. Stage 1 (filter and ECU only) tune gets around 400hp. That's on a MAHA dyno. Please read the entire FB thread (incl. Comments/Replies) https://www.facebook.com/9x1.org/videos/882650535269493/ and search for threads on 718Forum.com discussing Ehresmann. A couple of European forum members have been in contact with them and were planning visits.

Also see our discussion threads on the Cobb tune results and on VTG and compressor wheel size generally. Most tuners apart from Ehresmann seem constrained on peak hp (as opposed to torque/average-hp) with the 2.5/VTG. Could be heat or back-pressure or compressor-size constraint, but Ehresmann Stage 1 result suggests that the real constraint has been tuning ECU for the new VTG technology where internal wastegate and vane-angle are controlled together with a common actuator.

Reliability of turbo tunes generally is another topic unto itself -- I recommend researching the thread history on PorscheBoost.com while bearing in mind that the 9A2 engine architecture is common to the B6 (Carrera) and B4 (718) variants, while the B4 2.5 bore/stroke, valve-size and VTG turbo are shared with the 911 Turbo/S/GT2 engines. Most of their tuning focus is and has-been on the sixes, but concepts and insights apply to the B4 cars as well.

 

[[email protected]]

We're a COBB pro-tuner and have been using their products and working with them for a long time! COBB's OTS tunes are conservative. I tracked my STI doing 30+ days on track a year with a Stg 2 91 octane OTS tune with no issues. Different car and different power levels but the point is I used their conservative OTS offering and it made great power with stellar reliability. COBB does not inflate their dyno numbers. Look at their NA tunes for an example of this.

Being able to have your car pro-tuned is a big benefit over some other one size fits all tunes. Not bagging on anyone but being able to get your car dialed in EXACTLY the way you want it is nice.

I fully appreciate the concerns about warranty. However, my focus was on a 911 (essentially for the 2 reasons of power and engine/exhaust sound) but have decided I'm not willing to pay more for a flawed vehicle (and then they want you to pay for rear steering to help make up for it) . (gasp - I said something critical of a 911) I'm not looking to start a debate on that subject - just explaining my own personal thoughts.

If I can get some reliable information about tunes on the 718 then I could potentially solve for (my perceived) power deficiency and have 'the perfect car'. (except for the exhaust note).

 

[sweetsound]

@Zuffenhouse and @Joshua

Thank you for the feedback and links. Gives me some items to research!

If anyone has any other links/info - please post.

BTW, @ Zuffenhouse. Love the look of that car on the dyno. GT Silver with only the 718 badge is gorgeous.

 

[ZuffenHouseRules]

@ Zuffenhouse. Love the look of that car on the dyno. GT Silver with only the 718 badge is gorgeous.

Agree, but that's not mine -- although I ordered GT Silver (twice) I ended up with Jet Black. And I'm in Calif. not Germany. Thanks though!

btw check out the flattened top of that baseline power curve for the S on the MAHA dyno. All the way from 5300 to 7300 rpm power is within 20hp of peak.

 

[8833]

Just a note of caution. I added a Max951 chip to my 1987 944 Turbo that I owned for 23 years (sold it two months ago to fund future purchase).

The Max951 chip did deliver a tremendous increase in power- just tremendous. But it also caused my exhaust to smell. Software tunes if modest are likely okay. But adding 50 hp to 350 is likely to fall into the category of "more power, but also unintended consequences".

Good luck

 

[Baka1969]

1) Power
2) Cheap
3) Reliable

pick two


There will never be enough.

The funny part is that automobiles are more powerful, quicker and faster than ever before. Plus the ability to put all that power to the road is better than any time in history. Yet, it's not enough.

A base Cayman with PDK and Sport Chrono with a "modest" 300 hp can do 0-100 in 4.3 sec and the 1/4 in around 12.5 sec. Even 10 years ago that was really flippin' quick. The 365 hp GTS shaves 0.5 off of those numbers.

My last 94' C4 300 hp Corvette did them in about 5.5 and 14.0 respectively.

Yet, we're not satisfied? When will there ever be enough (usable) power?

Maybe we've reached it? Many of today's "super" cars produce way more power than can be used on the street. Sometimes to the detriment of having as much fun as the car can give.

Would you rather use 90% of a car's potential zipping around the back roads or only 10% of what a car has?

Yeah, yeah, knowing that you could has its pleasure too. But, how much fun is an 800 hp road-legal drag car that can only be blipped without the real potential of losing one's driving privilege?

But! A 300 hp sled can be used to much more of its abilities. Even legally.

I know! I still want MORE POWER! Not that I'll use it. But because it's there. Right? lol

Just a little fun.

 

[[email protected]]

We should all drive a Miata or BRZ by that logic...

I do agree cars have come a long way! My Cayman has ~500bhp and is a handful to drive and rarely sees WOT on public roads, it's still a lot of fun

Would you rather use 90% of a car's potential zipping around the back roads or only 10% of what a car has?

Yeah, yeah, knowing that you could has its pleasure too. But, how much fun is an 800 hp road-legal drag car that can only be blipped without the real potential of losing one's driving privilege?

But! A 300 hp sled can be used to much more of its abilities. Even legally.

I know! I still want MORE POWER! Not that I'll use it. But because it's there. Right? lol

Just a little fun.

 

[Baka1969]

We should all drive a Miata or BRZ by that logic...

I do agree cars have come a long way! My Cayman has ~500bhp and is a handful to drive and rarely sees WOT on public roads, it's still a lot of fun

The Miata is really only fun in the twisties. It is severely underpowered by almost any objective measure. I just don't think it's all that fun for everyday driving.

On the other hand, the Cayman (even in base form) will give you a kick in the pants off the line and will be fun for back roads. I believe the Cayman can be exploited using most of its potential in a lot of daily circumstances. It not as narrowly focused like the Miata or something like the Dodge Demon.

Of course I'm not anti-power. I just want a sports car that I can have fun using a good portion of what the car is designed to do and do it daily.

I have nothing to back this up, but, I would think a 400 hp Cayman with Sport Chrono would be the perfect balance of everything. As long as it's not too high strung. I'm waiting for the next GT4 to deliver that.

 

[Chiraoka]

AFAIK, there are two "known" differences between the 718 S and GTS engines:

GTS inlet manifold

And same Cayman S turbo with larger compressor wheel.

"The new car’s 2.5-liter produces 15 hp more than the four-cylinder in the current Cayman S, thanks to a revised intake duct and a larger turbocharger compressor wheel, the latter helping to raise boost pressure from 16.7 psi to 18.1. The engine also makes 25 hp more than the previous-generation Cayman GTS’s naturally aspirated 3.4-liter six." https://www.roadandtrack.com/car-culture/a19694790/2018-porsche-718-cayman-gts-first-drive/

"The increase in performance is made possible thanks to a redeveloped intake duct with greater volume as well as an optimised turbocharger with variable turbine geometry (VTG) and increased boost pressure. Instead of a maximum boost pressure of 1.1 bar as seen in the 718 S, the optimised single turbocharger with VTG and a larger compressor pushes the air into the combustion chambers with a pressure of up to 1.3 bar. This means that the high torque plateau begins even at a low engine speed of 1,900 rpm and remains at the maximum value all the way to 5,000 or 5,500 rpm." https://presskit.porsche.de/models/...cayman-gts/topic/performance-and-engines.html

Wonder if there are more differences, maybe a different exhaust manifold ....

 

[8833]

AFAIK, there are two "known" differences between the 718 S and GTS engines:

GTS inlet manifold
And same Cayman S turbo with larger compressor wheel.


Wonder if there are more differences, maybe a different exhaust manifold ....

An article in Excellence magazine claims the engine note is different (possibly better) in the GTS because of the different intake manifold. This may be difficult to judge in practice.

 

[Chiraoka]

I had a couple of subarus in the past, and in order to have a different engine note (noticeable) was changing exhaust manifold ...

 

[mlpor]

Ehresmann Automotive GmbH gets 450 crank hp on a 718S 2.5 with their Stage 2 (downpipe) tune. Stage 1 (filter and ECU only) tune gets around 400hp. That's on a MAHA dyno. Please read the entire FB thread (incl. Comments/Replies)

https://www.facebook.com/video.php?v=882650535269493

and search

Thanks for the post and information. I'm having trouble understanding the power vs. torque graph (both attached & the video of the dyno tuning run.) I thought power (bhp or PS) and torque had or should cross at 5,252 rpm? I've assumed the x-axis on the graph is rpm, but I can't figure out why the cross over is taking place at @ either the 3,500 +/- mark (orange line on red) or the 4,100 +/- (orange on blue) mark? Is it a PS vs. kW vs. Nm vs. lb-ft conversion or something else I'm missing?

Last, anyone know what the bottom, green "Schleppleistung" line represents? My google translation efforts are getting something like "power station" or drag power?

Thx

 

[982CS]

Last, anyone know what the bottom, green "Schleppleistung" line represents? My google translation efforts are getting something like "power station" or drag power?

Thx

Isn’t it just the delta between the two runs?

 

[mlpor]

Isn’t it just the delta between the two runs?

I don't know, but your question & my lack of knowledge sent me off on a further google search for more information. FWIW,

How to read dyno graph (raceenginesuppliers.com)

which provides " . . .Power on wheels (1) is shown in blue, the power of resistance and loss (2) with a green color, then normalized engine power - that is the one that we are most interested (3) it is drawn in red and finally normalized torque (4) - orange. . . ."

 

[johan]

More on Maha, read the first post

How to read a MAHA dyno sheet

First thing we learned about using the MaHa lps 3000 Is… forgetting everything you learned about all other wheel power calculating dynos. This is what we had to do, Joe and I have been using other dynos for years to tune and test cars and we put up some resistance at first until we unlearned...

www.vwvortex.com

Also, Porsche states no correction value should be used.
So Jens for ex never uses P-norm,
Also from what i know it is important not to downshift on a Maha after the run.
Just release the thottle and let the wheels roll down to a certain speed.