Octaviosa

Hi, I am considering installing an IPD plenum on my stock 997.1 - has anyone installed this IPD plenum in your 997 and are there any clear benefits worth the expense? Manufacturer claims 28 HP gains which sounds a bit too good to be true. Thanks folks.

wjk_glynn

8x57IRS

Very interesting, always believed that this gains something.

svandamme

I've yet to see a decent before and after Dyno for the IPD that actually shows what IPD claims it will deliver.
At best somebody did a chiptuning at the same time they installed an IPD, and exhaust work
but
Stock to IPD+exhaustwork+ chiptune does not show the IPD's result, it shows a combination result of all those things where the chiptune and exhaust are likely the bigger gains.

What I would like to see is an already optimized, chiptuned car
dyno
install IPD
redo the chiptuning
now dyno the 2nd time.

I don't think its worth the cost of all that for the marginal gains that can be found from such a slight intake mod


if you ask me their marketing is solely based on stock car, add IPD, and then tune , presto, They have their claim , but its technically not the product that delivered it.

Butzi 997

I'm not, remotely, an engineer, but I think on NA cars you'd have to have what amounts to a complete system change for the air management starting with headers to plenum to throttle body to ECU tune to find HP/Torque improvements you can feel. I tend to think aftermarket airboxes are all louder and just make you think you have more power.

When I modified my 2017 BRZ I bought headers, an E85 flex fuel kit and a tune and the results were undeniable. Now I have an EVOMs tune (which made a difference i could feel) and I'm tempted every year to get Soul headers for my .2 for the sound alone, but...that's a big chunk of change for a car I'm already very satisfied with.

My big chunk of $$ this year will be taking 34.8 lbs of unsprung weight off the car with 18" forged wheels, but that's mostly for ride quality. I'll be pleasantly surprised if there are noticeable handling improvements.

Petza914

Probably not much thwr efrin the ipd. That video people keep using as evidence is awful though. First, you'll never recreate the same airflow into the air intake with fans on a stationary car as the car what's when driving down the road, 2, and most importantly, they never reset the DME and had the fueling relearned before doing the after Dyno runs. They also didn't track fuel trims to see that the car was probably running lean from the extra airflow after the intake change before it relearned the new fuel requirements to mix with that air. At a minimum, they should have disxinnecedt the battery, driven the car for a half hour, then duno'd it.

Great idea for a comparison video, but the execution makes the results and conclusions useless.

For a better real.driving situation comparison see this - https://rennlist.com/forums/997-foru...surements.html

PCarFan16

I installed the IPD plenum when I had everything apart to replace the starter cable. Subjective change was minimal at best and probably just confirmation bias (that plenum is expensive!). I then added the EVOMS intake and again, no real subjective change (not even noise, although I had previously done the intake resonator bypass). Finally, I added the Softronic tune which improved throttle response(simply due to throttle by wire remapping) but really accentuated the torque drop between 3-4k. Softronic attributed that behavior to aftermarket intake and plenum, opining that stock is best on these cars. I removed the intake after a UOA showed elevated Silica. Subjectively again, no real change.

it’s important to approach any of these mods with a skeptical mind, knowing that Porsche likely wouldn’t leave much on the table in terms of performance (exhaust sound being the exception). I like to tinker so have enjoyed trialing these relatively easy mods, but at the end of the day, any changes are very minor at best.

hexagone

I had a base 997.2 car with a tune, headers, IPD plenum and airbox (bought it that way - oriented for track use)

and side by side owned a base C2S...

There felt to be an eagerness on the top end on the base car, but not one I would've spent the many thousands it cost to do the work. Out of the box I liked the "usability" of the C2S more.

RDS928S

IPD plenums are only benificial on forced induction motors.

jamesinger

I have been trying to cobble together as much of a bootleg X51 package as possible for my 997.1 C2S. So far, I have the BMC filter, IPD intake arm/helmholtz block, GT3TB, IPD comp. plenum to X51 headers into stock cats and Fister mufflers. As a normal guy, I never noticed any HP/TQ gains from these mods BUT the sound is worth it IMO.

(in order of install)

1. The BMC filter alone changed some induction noise.
2. The Fister cans to me are indiscernible from PSE just with permanently open valves.
3. The IPD Plenum and GT3TB with helmholtz delete totally changed the sound over 5k to an absolute WAIL. There is also slightly more low end induction noise when you are in a quiet area that you can hear those nuances in (i.e. NOT in traffic).
4. The X51 headers deepened the exhaust tone and added some more burbling. The noises the car was already making were dropped in tone and slightly amplified.

I also like how the throttle and all feels now over stock in normal mode. The IPD plenum with the GT3TB really changed the sound over 5k. I think if I was trying to squeeze more HP out of this engine, I would try to get headwork done but I would also FOR SURE get High Flow Cats and a custom tune AFTER all the mods had been installed. If you aren't freeing up the bottleneck at the cats, I argue your gains in an NA car will be minimal. I am not sure about other people but in the NA cars I have had, I just try to get the car to breathe better. Any mods I have done beyond that have mostly been in vain and usually cause more problems than power. In my 911, I have used what I learned from various NA cars over the years. If you really want to make power: 1. Get that 4cyl turbo 718, which could be made INSANE with a few mods, or get the 991.2 3.0 motor with the TT and you can make BIG power. From my experience, forced induction is a whole lot easier to do a mod where after you are just blown away. Most NA mods are just like, "hmmmm, well it sounds a bit different..." lol.

workhurts

Speaking of air flow, is there a consensus a d cheap/good easy to install 200 cell cats or headers? Might be my next project.

jamesinger

IDK if this is normal in the Porsche world but with previous cars, I modded my OEM cat. On E85 cars, I could just run a 3" pipe through the shroud because it is E85. If you do that with 91+, it will smell and make your eyes water. Cops too. lol. However, there are shops that I have had OEM cats converted to HFC, so OEM shroud, HFC inside. Passing smog in CA is a crap shoot regardless in my experience. I was just talking to someone about how I got failed on a 100% stock EVO for having a "shiny pipe." LOL.

...but Soul and Fabspeed and everyone and their moms makes off the shelf ones too.

okbarnett

I had a 3.6 996 and I put complete free flow exhaust, k&n intake and ipd and revo stage2 tune. It all worked great togather. I believe the ipd did benefit with all the other factors working with it. I dont believe any one thing makes a different on its own, except a tune, to its capability