There has been a lot of discussions on different packages and parts, so here is my understanding and interpretations. I'm pretty new to turbo tuning so bare with me. Meth/Nitrous kits are not something that I am interested in doing so wont be summarized here.

COBB/GIAC Software - Both offer proven results in whp/tq improvements

Higher flow exhaust system - No debate here in their contributions to performance when paired with software.

Intercoolers - Proven results in reducing heat while allowing higher boosts which adds to performance, stability and reliability.

Bigger Turbos - Proven results in increasing airflow and efficiency, which yields to better performance.

Intake - Have heard mixed results from customers, basic airfilter drop might be sufficient.

Headers - Mixed reviews. Equally vs unequal length, Coated versus uncoated for turbo cars.

IPD Plenum - Mixed reviews.

IPD Y Pipe - Limited reviews, I'm not clear that if they add any thing.

Diverters - Limited reviews, this is a failproof product, not a performance mod.

 

You can read my thread about the differences in HP gained with boltons only. My car with exhaust, headers, Plenum, Ypipe and ICs makes 520whp with the stock ECU, no tune or piggyback installed. I think that is around 70-90 more than stock. Before the Ypipe and Plenum I was getting 475whp with only the exhaust, headers and plenum on the stock ECU. I tabulated everything in my thread on the Ypipe and IC install.

 

Thanks WRS, I did read your extensive review but recall that the Y pipe and IC were installed together, therefore it doesn't show that how much Y pipe has contributed.

I don't mind paying for mods but too many components introduce bigger risk of connectivity failures which outweighs the debatable performance gains.

 

Great questions. I agree that tune, intercoolers, free flow exhaust and bigger turbos are the main and proven gateway to lots of additional power.

Both GIAC and Cobb tunes makes our cars dramatically faster than stock. The easy of use of the Cobb Accessport is a huge plus for Cobb and seems to be gaining it a lot of customers here. GIAC's long history and experience with tuning Porsche Turbos and keeping good reliability drew me to them.

My own impression is that the Cobb tunes are a little more aggressive and make a little more power than their GIAC counterparts. I cannot comment on whether this is good for the cars' durability or not or whether our cars will last longer or the same with GIAC vs Cobb -- only time will tell. Putting any tune on a $200k car is always a calculated risk to me as you are pushing the car harder than the factory set it up to be. It is a calculated risk I am willing to run BUT I would give up a tiny bit of speed if I knew it was better for the car's durability. Unfortunately we do not have a consumer reports magazine to test our car's mods for things like reliability.

Intercoolers: to me this is the single most important mod other than free flow exhaust if you want big-time power out of these cars. The stock intercoolers are a joke and are paperweight light. I have held them in my hands after I replaced them. I know the Champion ones are dramatically heavier and larger than the stock ones as I have held them too in my hands. I think people who want power would be well served to get one of the competing intercoolers out there be it Champion, ByDesign or AWE. Kudos to all of these companies for getting them to market.

Without the upgraded intercoolers, the GIAC stage 2 tune (which is for the stock ICs) cuts power dramatically after the first run to keep the intake air temperature is from ruining the drivetrain especially the turbos. I ran against several Cobb stage two cars at Atco all day in very warm conditions in the afternoon and did not see their ECUs reducing power at all despite their stock intercooling. That raised the question in my mind as to whether the turbos were being exposed to too much heat. I don't know if they were but it concerned me that they were not losing any power after so many runs hot. Maybe Cobb found a way to make so much power on stage 2 without generating excess intake air temps or they know something about tuning that GIAC does not. I just don't know how they did it.

Free flow exhaust: without these you cannot get much additional power from a tune. These unlock the big power. There are so many excellent exhausts out there. I loved my high flow cat Europipe and love my Tubi catless. If you go catless you will get a little more additional power at higher RPMs but it is not super dramatic.

I have not had the pleasure of hearing most of the many exhausts out there. I do note that besides EP and Tubi, Kline and GMG have gotten some solid reviews. I despised the sound of my friend's Fabspeed catless. Mega drone and way way too loud for my liking. But if you want as much sound as possible it will do that.

Of all the exhausts I have heard the Tubi catless race is the highest pitched. Almost Italian sports car sound like under load. I loved it but Porsche traditionalists who like a lower pitched exhaust note may not like that.

Bigger turbos: Emre from Turkey, as always, is the first on the market with these. His results have been astounding (9.5 ETs). ByDesign and Champion should be out with these very soon in the US with ByDesign releasing first. We will soon see how much faster our cars get. I am guessing 650-680 wheel hp from what I am hearing. The first speed event where these will likely be out is the Wannagofast 1/2 event in Ocala, Florida on Jan 23-24. I will be there -- hopefully with upgraded Champion VTGs by them. I sure do hope to see my
Cobb/ByDesign friends' cars there.

The diverter valves are simply to prevent a potential source of boost leaks caused by the greater propensity of the OEM diverter valves to fail under the increased boost of the tuned cars which they were not designed to handle.

Intake: I am very specious about the capability of an intake to offer more power. I know one respected member here who told me that an aftermarket intake caused his car to lose power. I was approached with a sponsorship opportunity for an aftermarket intake and responded that I would Dyno it independently and that if it lost power I would return to and would want a refund. The aftermarket company told me they would have to think about it and I have never heard back from them in months.

Headers: the story of my own Dyno of the FVD headers is well documented by me here. At least with the GIAC tune they lost power despite GIAC's attempts to wring power out of them.

I now see that ceramic coated headers are part of the ByDesign Stage 3 package. I have heard really great/rave reviews of the Kline exhaust but have not seen feedback on the headers. I wonder whether their ceramic coating has any effect on the temperature of the air going to the turbos. I assume the ceramic coating keeps the air hotter. I don't know is the effect of that air on the turbos and whether this enhances performance or has any impact on lifespan. And I don't know if there is anything in the Cobb tune to take that variable into account. I'm sure Cobb can chime in.

IPD Plenum: I have heard very mixed reviews terms of whether this might actually gains or loses power. I don't know the answer. I am actually going to be removing mine and returning to the stock plenum based on some of those reviews.

IPD Y pipe: Heard some mixed views here too. There have been some hiccups reported to me at least in the early released Y pipes. I know of one instance reported to me where a ByDesign/Cobb Stage III car owner removed the Y pipe to compete in a speed event. I didn't hear it directly from the owner but rather from one of the owner's close friends. So I cannot guarantee that the report was accurate although I trust the person who told me. That was very early on after the release of the Y pipe so perhaps those teething issues have been sorted out by now. I Don't know as I don't have it. The IPD Y pipe looks fantastic and looks visually like it could add some nice power. That's why I wanted one on my car but it didn't fit. Grrr.

 

The stages are used to help identify levels especially for the purpose of a continuation from a previous stage. It really comes down to the provider and their descriptions and results. You have to find someone you're comfortable with and be comfortable with their ideology.

Just a note I would like to share with the community. We have had the turbochargers off of about 8 cars now. Upgrading and tuning has been going on intimately and truthfully. We have noticed that high mileage or low, the turbochargers take quite a beating if the car is not allowed to cool down properly when run hard. I have seen evidence of wear from factory to every tune out there so far and mileage from 1500 to 30,000. So it's not a finger-pointing thing. No matter what you do to your car and let it properly cool down and I don't for a few minutes before you shut it down. These cars are so smooth and reliable we forget what type of numbers are being produced. When you see glowing red hot headers you can only imagine what's going on in there and if you shut the car down it's never good. Otherwise everything is quite robust and when treated properly you should be fine at every level!

Cheers

 

I know, but I haven't been able to document just one thing at a time. It would be nice if we could but Aristotle said the whole is greater than the sum of it's parts so you could just say OK, there are two configurations of boltons where I know what the whole amounts to irrespective of the individual parts. I was surprised to get 45whp from ICs and the Y-pipe and when you look at the plots you can see the biggest gain in hp is consistent up top above 5000 rpm where you really want it and the torque band is wider and substantially higher. So I was pleasantly surprised to see how much I had with just boltons, it was almost as much as I had with a custom tune and the other three boltons prior to that change.

We know that the FVD headers dropped hp for Scott's configuration and in fact, I think they or something affected the FVD piggyback because with just the boltons, there was no dip in power absent the piggyback or tune, it is a smooth curve in both cases. However, on my car with the FVD headers, IPD Plenum and FVD exhaust, there is a dip in HP with the piggyback below the boltons only from 4400rpm to 5600rpm. Overall power is higher up top as desired but that dip is there.

Finally, the Y-Pipe and Plenum are not adding any new connections, they are just replacement parts. Maybe different fasteners but same connections.

Net result is that I am pleased with what the dyno results show for my car but my testing out at my county road yesterday was still not what I am looking for yet. I changed where I started and the traps were 2-3mph higher but the car was going uphill 15 feet in the first 1/8 mile and I still had traction issues but IATs were 15 degrees lower. 60ft was still 1.6 to 1.7 but I had tire pressure at 35 all the way around. I was way out in the country and didn't want to take too much air out. At the track you can add air back in before driving home. So I still have work t do in order to get the real results I am looking for and I can only do that at the dragstrip.

 

That is great advice. We are indeed all pushing the turbos harder than the factory. Which is why I want some bigger VTGs.

 

I think Emre's are smaller.

 

They are all bigger. But the trick is to just let the turbochargers cool down before shutting the car down. There is a oil and water running through them. The oil is very thin and they get pretty darn hot! So it literally Cookson leaves deposits when run hard and put away wet as they say. Remember that his stock, upgraded, tune or no tune.

 

[QUOTE=wrs;4423641]
Finally, the Y-Pipe and Plenum are not adding any new connections, they are just replacement parts. Maybe different fasteners but same connections.QUOTE]

Understood. I just don't want to troubleshoot each component and their connections when something goes wrong. I don't have a local installer or an expert like Sam locally.

 

Cheers John. I'd be glad to reach out and support you step-by-step from here. How far are you from JR at redline speed works? To get critical you need a Dyno however, if you wanted to explore the benefit of any components individually I am game and confident with confirmed data.

 

Sam if I get something I will probably get it from you, post sale customer service is very important to me. However, i'm not sure if its worth your time since I might be only getting the IC for now.
I am 90 minutes away from RSW so it's really not convenient. It's a shame that there are no pro porsche installer/tuner around the NYC area.

 

Just to clarify, you've removed the turbochargers for the purpose of upgrading, correct? Were there problems with those turbos, or just removed for the purpose of upgrading? Were the cars that had the turbos removed stock or modified?

I'm sure a lot of information could be obtained by evaluating the turbos from stock cars and modified ones and comparing them. I would imagine mileage plays a role as well.

I understand the rest of what your saying, let the car cool down after running it hard. Great advice!

 

When the car is hot, don't the fans keep running after you shut off the car?

 

Yes but probably better to leave the engine running to circulate oil and let the engine get some fresh air.