Hello members!!
Well I hope some experienced member can help me understand Cobb tune, without starting a war!!
I had Cobb AP for 2 months now. I have nothing but good things to say about Cobb's power and car drives a lot smoother then stock.
So I went up from Cobb Stage 1 to Cobb Stage 2 ( FVD 200 Cells Cat exhaust system ). Now recently I just had a Cobb Dyno Pro-tune..
Here is something I do not understand.I have contacted Cobb but then answer they gave, lets say " user friendly"
Of course I understand," at the end of the day hp gains are different for everyone and there are many variables that go into play when measuring those numbers, fuel type, temperature, different dyno's will give you different numbers, etc."

Ok . From Cobb Website it says Stage 1 gain about 10% HP 8%TQ. So that will be 480HP out of the box + 48 ~ hp should make the car around 528HP.
Now the Stage 2 require an aftermarket exhaust. gain about 17%hp more will make the car about ~ 561HP

Now after the Pro-tune. The Car now makes 550HP ( 450 WHP ) and 500TQ, The tuner told me he picked up about 50HP over the Cobb stage 2…
BTW the Pro tuner was a great guy to work with...
For my car the Stage 1 and stage 2 almost same power..
So my question is .. Protune pick up 50HP that make the Cobb stage 2. 500HP. Which only 20 HP more then the stock? Also on the dyno Cobb stage 2 showing 400WHP… 400X1.23= 492HP . What happened to 17% to 24% gain?
I have a friend who has the same car as my, and runs with GIAC stage 2. On dyno it came out close to 600HP and a lot more TQ than the Cobb.
Please do not get me wrong, I love the Cobb AP and power.. just want to understand where all the power went?
Here are the dyno sheets.
Thanks for all your help...

 

seems like a low reading dyno, the stock vs final tune looks like a good pickup. That's my impression

 

Dynosheets are "useless" without a base run before tuning. Different dynos read different #`s and are meant for tuning. When tuning, use the same dyno to compare results for each thing you change.
You are after the delta when doing mods.

 

So true, only the delta means something

 

 

I can tell you from personal experience my Supra makes a 100hp difference on a DynoJet versus a Mustang Dyno. Overall it sounds as if your tuner has created a tune specific to your car and the conditions that day and all is well. Don't be stuck on the numbers, its all about the drive ability.

 

Yep, I made close to 830 in my Supra on a dynojet and about 745 on a Mustang dyno. They read different.

 

I thought also kind low...

 

I agree with you... but is kinda shocking to see that Cobb stage 1 and 2 are the same power and only picked 20 to 30 hp more then the stock for my car..

 

We have same car all 2008 997.1 tiptronic turbo.. he has GIAC stage2 ... even on GIAC website showing 570 hp and 590hp on rice mod, I think..

 

Yes I am thinking maybe do a different see the difference?
My dyno graph is kinda all over the place.. I do not know if I have a boost leak or not... Also I just noticed I set shift at 6500 RPM from Cobb AP.. that may have something to do with it?

 

I only have a 997.1 Carrera S, but why does Cobb think they "know" better than factory Porsche? I am new so be easy.

 

Maximum dyno numbers aside, your car didn't like the off the shelf Cobb mapping that was loaded. See how wavy your curves are? That's all signs that the ECU was unhappy about something and was likely pulling timing and possibly boost to correct for it. This is a great example of how pro tuning and mapping each car is by far the best solution. Every car is different. Mine required base fueling changes even with the stock injectors to get the short term fuel trims in check.

Finally, you can see how much smoother your graphs are after the pro tuner was done. It is obvious the ECU is no longer reacting to issues with the tuning as before.

 

Manufacturers build their vehicles with a specific safe and carb compliant tune. These cars are usually built for the average customer who intend to keep the cars stock. The cars are usually built with basic specs that shouldn't vary from one another and loading a safe tune ensures that the engine is kept safe. Due to varying elevation, temperature, and density factors- the tune is usually pretty rich to avoid detonation. There is always room to custom tune for your own altitude, temperature, driving style, etc.

If you begin to modify the car- for example you add aftermarket parts, you would need to tune the car to take advantage of the increased airflow, fuel, or spark. This is where companies like cobb come in and offer customization. Although I had a horrible experience with cobb since they used 09 gtr owners like testers- they make a decent product. I'd personally go with another company since the customer support from cobb in 2010 was such garbage and they would over promise and under deliver on the GT-R tunes. If you do buy the cobb- get a custom tune done and stay away from the OTS tunes.

 

I agree pro tune is the best solution. Do you think a TCU Tuning from EVOMSit EVOMS. or GIAC with my Cobb ECU tune will be a good idea?
Is TCU upgrade make shift faster? TCU from GIAC stage 2 said will shift like PDK???