BogdanR

OK my friend... the suspense is killing me... Did you ever get this dyno done? And the results... Good?... Bad?... Ugly?!!?

I'm just curious nothing else... I picked up my 997.1 a week ago and I'm slowly discovering things about her I haven't actually paid for... Like an IPD plenum and an updated exhaust I yet have to identify... My discoveries are slow because I enjoy the drive WAY too much to stop and prod/ pry at all de details...

It felt different from all the 997.1 C2 I tried to begin with if I'm honest... Nothing ground-breaking but a bit more responsive especially in sport mode, with a bit more push "authority" off the line and definitely a louder, sweeter exhaust gargle (that I can't seem to get tired of, not now nor ever). All of this even before I realised there were more things done than the Fuchs and the nice, discreet Techart trim...

For a Porsche complete neophyte (which I am) all the above might sound like pure rubbish (which 95% probably is) however my engineering background and job (automotive systems development/ testing) made me extremely sensitive in feeling this sort of "off norm" changes...

The same background however heavily relies on hard data collected on tests/ trials, that's why I was curious as to why there was no follow up to this thread.

Sorry to bring up another beat up, nearly dead horse...

USMC_DS1

Congrats on the new ride. This is also my 1st p-car and after 3 yrs it still puts a grin on my face although I've added a few more mods along the way since the IPD plenum was installed 2 yrs ago. https://rennlist.com/forums/997-foru...r-carrera.html

FWIW, I did get the car dyno'd but it was not w/o issues. Although she produced 320 RWHP on a warm day... I believe that there may be another 5-15 RWHP left untapped as the 2WD dyno triggered limp mode. Apparently, our cars require an AWD dyno system. Here's a prior write-up with dyno results and explanation. https://rennlist.com/forums/11112782-post50.html Regardless of the dyno results... the car is more responsive and has more mid-range than it did in stock condition = more grin factor.

BTW, you may want to post pics of any markings on your exhaust system. Someone on the RL may recognize it for what it is... GL and enjoy the ride.

BogdanR

Thanks for the reply , much appreciated
320 RWHP on a hot day is not too bad if I'm honest...

I might do that at some point... but for the time being, getting inside and driving it beats the hell out of crawling under it taking pics of the exhaust :-)

TrackDays247.com

We dun got em in stock and ready to roll - :-)

PTParks

Even if it wasn't producing the advertised 28 HP gain, with what HP costs in the Porsche community to begin with, even 10-15 HP over stock for $1K is a pretty good bargain. Why didn't Porsche design a better plenum? R&D ("hey, this'll work") and manufacturing costs (simple plastic vs cast aluminum) pure and simple.

TrackDays247.com

I've hear the theory of placing a model HP at a level so as not to compete with a more expensive model with nearly the same engine...one method

RobC4sX51

I would believe more like 2.8 hp and 2.6 torque increases! But I agree in the incremental approach to improve these engines. A slightly better exhaust system, a slightly better intake system (including K&N filters), an ECU tweak, and maybe we can squeeze another 20-25 hp out of the stock engine. But the plenum by itself cannot do that! The IPD does look really cool but then after it is installed, no one but your mind's eye can see it! Great write up. Thanks.

RobC4sX51

The IPD website says 12/14 hp/T is possible and the dyno shows it. I retract my 2.8 & 2.6 hp/t comment but I'm still skeptical! Any other installs have experience?

Redline911

I had the Plenum installed last week. My shop did the break in procedure (per my request.) There was a noticeable difference on my drive home. The car absolutely pulled from 4k to 7k quicker and more smoothly. It caught me by surprise on the first few pulls, had to adjust and shift sooner. Other than a Fister exhaust I drove the car bone stock for 18 months so I think I had a good baseline to compare to. I considered doing a before & after dyno, but honestly I really don't care if it gave me 5, 10, or 15 HP. It did make a difference, and that's what matters. So is it 28hp, no......but I believe 10-15. I'm a satisfied customer.

USMC_DS1

FWIW, I recall feeling more pull in the mid-range after I installed the IPD plenum a few years ago... before all my other mods. It's a fairly inexpensive and easy initial mod. I've since gone with the competition plenum and GT3 TB.

user 72902

I have the 82mm IPD plenum + TB, full Fabspeed exhaust and competition intake so there are a lot of variables involved. My sphincter is not calibrated so I'll have to wait for the post-dyno results but I would expect to see an improvement.

RobC4sX51

Thanks guys. I will get back with my experience after install

ALEV8

Just realized this in in my car...........

Blue Chip

I don't know that I really felt any difference... I already had an EVOMS intake, and an exhaust. Added the plenum later... it didn't hurt - but not sure of the gains.

user 72902

I changed back to the 74mm IPD plenum. I also have headers, sport cat, and non-stock mufflers. The difference between the before and after dyno was like 33hp and 34ftlbs torque. There are a few more factors to muddy the waters 1) different dynos and 2) a professional custom tune but those numbers should be representative of expected returns from the above mods. To what extent the plenum played - who knows.