I know this subject has been discussed many times, but has anyone seen HP gains from either the IPD plenum or bypass pipes (before and after dyno) ? I currently have GIAC tune (2014 CTT) and I'm quiet satisfied but would like to see what my additional options are.

 

Well I don't know if anyone has a dyno sheet to prove it but the general consensus is the secondary bypass pipes will get you a few hp but not a lot. As for the IPD plenum nobody here that I know of has been able to prove the claimed 30+ gain.

The bypass pipes will also make the exhaust note a bit louder, which I liked.

 

I was under the impression that IPD was going to dyno a CTT and post results but I have not seen anything !!

 

The 30+ HP gains from IPD is a joke.

 

It's not a joke. It says right on their website that there are gains. Are you saying it could be false advertising?

 

A fantastic sound and power gainer that is non-invasive and easy to install at home would be secondary catbypass pipes. The o2 sensors are in the primary catalytic converters but not the secondary cats, we can bypass them without the car even knowing they are gone for big gains.

We even see above 20 hp gains on some turbo cayenne models.

Which year Cayenne Turbo do you have?

 

2014 CTT, w/GIAC tune

 

Secondary Catbypass Pipes

In stock ready to ship. Simple install picks up sound, power and saves weight.

The true triple threat, I'll send you a PM now with some pricing.

 

I will purchase IPD plenum and bypass pipes only after I see Dyno showing claimed Horsepower gains !! I really believe vendors of these product would see a increase of business if the testing was to be done.

 

The bypass pipes have pretty well been proven to gain some hp. I don't know if anyone has done before and after dyno results on a CTT but I know it has been done on plenty of platforms. It is a pretty easy bolt on too.

AS for the IPD plenum..as has been mentioned it's been pretty well beaten to death and nobody including IPD has stepped up to prove the 30+hp gain claim. I even contacted them directly and offered to do the testing on mine. No reply at all.

Like I've said, on other platforms where it actually smooths a 90* bend into a nice smooth Y I can see it gaining hp. But our intake is already a nice smooth Y.

 

I got the IPD plenum. I do not care about the HP claimed. I would've returned it if I wasn't happy with it. In my case at least, it DOES work. I like how responsive the car became at lower RPMs. It revs easily and freely than before. If you know your car well you would definitely notice the improvements.

 

Yeah this looks like a good combo. I have the IPD plenum on my 991tts along with headers, high flow cats and sound exhaust plus a piggyback tune. The IPD adds power in the midband but not up top. You can see it as a bump in the middle of the dyno chart. The charts are right on their website.

My wife drives the CTTS so I don't want to do a tune but this looks like two boltons that would make the car more fun for me and she wouldn't notice. However, I have to say, after I added Dinan Stage 2 on my M5 she noticed and liked how it smoothed the car out.

 

Is the IPD easy to install?

 

I concur that the 30 day unconditional satisfaction promise from IDP is a great feature. I seriously doubt that they get many of these units back. NO WAY would I give this unit back to them. It completely transformed my driving experience on the car.


The only down side is that since I am now always on sport mode and always on the gas my gas mileage had really done down to insane levels - I got 4 MPG over the 100 miles since I installed the IPD unit.


I am curious to see what effect it is going to have on mpg when I set the cruise at 70 and roll down the highway - I would suspect that this unit will have some positive effect on MPG - although that remains to be seen

 

That is unfortunate for you. I can't speak on the IPD plenum nor did I or would I buy it. The bypass pipes is the best bang for your buck mod on a 958CTT. For less than $700 it almost eliminated any turbo lag and gave the V8 a great burble and rumble. I could care less if it gave 10 or 30 hp gains. The tune on the other hand you should care if it gives the advertised HP and that also costs a lot more.

Anyway do what you want.