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YOUR RESEARCHIPD intake Plenums. Thoughts?
Leading reported evidence
Install few ipd plenums
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Leading evidence: 'Install few ipd plenums' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'best bang' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Install few ipd plenums' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Mine is installed on a FSI 3.8L Stage II Track Performer , so I thought it an appropriate �upgrade�(along with the 80mm GT3 throttle body).
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Cost wise is probably the best bang for the buck performance enhancement.
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Suggestion
Or mine was, and was needed to fix the loss in torque the exhaust change caused.
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Suggestion
If you want more throttle response and to change your powerband go with software.
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Suggestion
Now the throttle has been bored, I�m running the Carrera 3.8 s airbox with a kN panel, I had soul headers but I sold them to squirrel and got his agency power headers, I also have a fab speed catless x pipe, and the fabspeed max flow exhaust.
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So many say it made literally little to no difference as a stand alone.
Was considering an IPD intake plenum for my (bored to 3.6), 1999 996 manual throttle. Heard that if you add one, it's not street legal anymore (California). Anyone have experience with them and what are the results? I'm a "passionate daily driver", no track use. Thanks in advance.
I just installed it on my 99 cable car and it did show a nice bump in power
but I had a fabspeed xpipe with 200 cell cats no muffler before
it’s definitely a better midrange punch
Do a search here� There�s plenty of info/discussion. Power gains? Hmmm� maybe, but #�s are questionable/controversial and are generally only realized in conjunction with other mods on the output side. Good luck!
Thanks to all of you for chiming in.
After doing some research, I saw some dyno pulls that were relatively modest gains (9werks channel) in conjunction with other intake and exhaust mods so there were not apples to apples. This (link below) video was the most balanced review I've seen from PCA and they admit that it was not about HP, but driving feel and lower end torque. Their DIY section showed breaking coolant lines to get in and out of the area, so I think I'll have someone do the install if I do this.
Here's the best I PCA video review I found so far...
You Tube
I did the installation myself, and did not break anything. Mine is installed on a FSI 3.8L Stage II Track Performer , so I thought it an appropriate �upgrade�(along with the 80mm GT3 throttle body). It has not been dyno�ed since coming home from FSI so I can�t comment on torque or JP #�s - �cept to say it runs great and pulls incredibly strong (came home with 306 bhp and has only gotten better in the 20k mi. or so I�ve driven it since).
Yes as a stand alone upgrade it probably won’t do a thing but in my case I already had the exhaust and competition air intake then I added the IPD and noticed a slight gain after all that
This is an interesting one.
Pca video took a stock 996.1 with no software or exhaust changes and it gains 10 hp? Sibley takes his 996.1 in with software and exhaust changes and gets a few hp as well. Does the plenum work on 996.1s? maybe.
All of the various video tests on the 996.2 and 997.1 (same engine) show it doesn't work. My indy even tested it on my 996.2 nearly 10 years ago on the dyno with the Gt3 TB, oem headers, fvd 200 cell cats and sport mufflers and it lost power. What power it kept was moved up the powerband to the midrange and high end. My indy has to tune the software to get back to even. At the end of the day, there was no performance gains.
FVD told me recently that the way to get the power out of the ipd is to do two things. (1) add a good set of headers to breath better. Obviously fvd recommends their m&m headers. (2) get your heads done.
FSI uses the ipd plenum in their rebuilds because they do head work and that works with the plenum.
Don't have an answer. Maybe it does work on the 996.1. Why? No clue. And I have no clue why they don't work on the 996.2/997.1 3.6 engine.
I have kept mine on the car because I like the giant sucking sound. Figure I will use them when I get my engine rebuilt with enhanced heads.
But in the meantime, i haven't gotten any power increase,, but my powerband changed.
Your call. Just calling it like I have personally seen it on my car with an indy that knows what they are doing.
Useful information for sure and thanks.
My M96 is a "minor freak" in that it has nickie sleeves (the cylinder cracked triggering the rebuild years ago) and was rebuilt, bearing dealt with, etc. and updated minor parts to 04 specs bored to 3.6. No special tuning and exhaust is basically stock though Fister made it sound like a P38 lighting which I give best mod ever before they raised prices.
I'm leaning toward leaving it alone
, although the plenum might have something to work with given it's bored to 3.6. Hard to say. I'm not inspired to redo the whole exhaust system, but might change out the intake hose and add the cap hack.
Any more thoughts?
You guys are all very informative, enjoying the conversation, thanks.
If you want intake sound, do the cap and tube. Fabspeed sells it I believe.
If you want to improve HP and TQ, the easiest way is to put on a good set of 200 cell cats. If you want more throttle response and to change your powerband go with software.
I do plan on adding fvds m&m headers sometjme next year which they state an improvement in lower end power. Maybe I finely pick up some benefit to the ipd/tb with the headers and gain 5-10 hp. Maybe not. But I will dyno it again and this time save the info to share.
Thanks, concise is good!
Look forward to hearing more about what you are modding in the future. I'll look into the 200 cell cats at some point too. I just did RSS Semi stiff mounts and so the C2 Cab feels great right now, and not too much noise or vibration, just good connected road feel.
Do what makes you happy. Whatever you do the gains will be modest. And the ipd plenum is pricey. I did a tune, headers, cats and valved exhaust and my 3.4 is more exciting, but it's not been Dyno tested so it could all be in my head. But it sounds like an old F1 car and I love that. The tune was done after the exhaust was, and really improved the mid range torque, but the most awesome thing is the throttle response. That, to me, it's the best thing about the tune, because you can feel it and use it. If you have a 99 or other cable throttle car, you will already be golden. But anyone with a 6mt and e-throttle who does not fix the response lag is very much missing out. Hard to heel and toe and double declutch until the fix is done. With it, is like shifting my old fiat spider, instant blips. But with horsepowers 😎.
you could try something like this
https://www.ecstuning.com/b-sprint-b...sbpo0033s~spb/
but honestly a tune is only 350 more. Or mine was, and was needed to fix the loss in torque the exhaust change caused.
I’ve installed a few IPD plenums.
Only once did I break the plastic coolant connector.
But I keep at least 1 aluminum connector in stock at all times and was able to fix it in about 5 minutes.
I�m my opinion the ipd works in my car. It�s a 3.4 cable throttle. Now the throttle has been bored, I�m running the Carrera 3.8 s airbox with a kN panel, I had soul headers but I sold them to squirrel and got his agency power headers, I also have a fab speed catless x pipe, and the fabspeed max flow exhaust. My car has an apr tune. Yes the plenum made a difference I�m happy. Another observation the agency power headers are 2 plus pounds per side lighter in weight than the soul headers, also the car sounds a bit louder with the agency power headers compared to the soul headers. I drove it Saturday to a performance shop anniversary event and I got compliments on how it sounds. A big thing is the weight removal, the factory mufflers weight a lot, so do the cats. I have removed the back seats and spare tire so Car has gone thru a diet. I really like the apr tune. Cost wise is probably the best bang for the buck performance enhancement. I�m happy with the plenum but look at all the other mods. Only way I can make my car faster is to get a bigger engine.
Would love to hear a sound clip. Sounds like you did a lot. Like so many, seems the plenum isn't that cost effective (if at all) unless it's done in the context of a larger series of upgrades. Still scratch my head on the PCA review of the stock 996 getting 10HP and increased torque. I love how IPD's ad in Panorama claims a 28HP gain. All things being said, passionately drove mine yesterday on PCH with the top down asis and smiled all the way to the beach. These 996 cars don't disappoint. Thanks!
IPD plenum "works" in the context of other upgrades because it isn't doing anything.
If the plenum had a reproducible effect it would be extremely easy to prove it. You would see an immediate shift in the fuel trims. VE would increase, etc.
I'd love another 20hp with no downside for a couple hundred bucks but it doesn't exist.
I�ve watched 2 videos ( PCA/9Werks) that show a 10 hp gain across the rev range on 1999 C2s.
Both were done the right way.
Same car, same dyno and the same day.
I�d call that something
Sure. Those 2 videos prompted this thread. The PCA one is the most puzzling in that it was a stocker that pulled 10HP on its own. I'm only looking for more fun/torque in the lower range, so that's what's most important to me. The tech in the shop I go to encouraged me to look at the IPD plenum as a single mod to do that, so.....that Intrigued me enough to ask all of you, and
thanks for the breadth of opinion!
@dougn
Vivid Racing VRTune. They asked which aftermarket intake and exhaust bits I had, I'm very pleased with the result. Easy procedure to back up stock ecu and apply vrtune.
Again I refer to this video which shows why these may not work as well as some believe. It's all in the intake temps and flow rates.
You Tube
Edit, I think the plenums work on the right engines. They seem to not do so well with stock to engines with basic modes.
Haven't found a test yet on yutube for a 3.6 m96 that benefits. Only the 3.4. The question is why?
What's so different about the engineering of a 3.6 that it doesn't work?
And what's so different about the 3.4's engineering that it does?
Is the exhaust airflow on the 3.4 greater than 3.6? If yes, and airflow through the stock plenum is the overall flow constraint, the higher volume plenum will help. WAG.
Yes as simple as that an engine is an air pump.
on a natural aspirated engine you need to have a little back pressure to load next
in. On a force induction engine turbo super charger, run it with as less restrictions as possible. I heard from a few people that the plenum works best on the 3.4
than on the 3.6. Just what I heard, I�m real happy with mine, but you have to consider all the other mods that the car has. One thing for sure, if you ever touch the factory piece when the car is hot is it hot, the ipd plenum dissipates heat better.
I ordered one just in case. Bought the IPD plenum. I decided to try the install on Memorial Day and once I got the throttle body off, decided after trying to get it out and almost breaking other stuff, that I was not in the mood to wrestle this thing out and force the other one in. Then a small nut fell into the engine bay....time suck for sure. A voice said, "that's it, the car is telling you something" so I retreated....put it back together till my mechanic has time to deal with it. Should only take an hour or two max for them. Kind of glad I did. Ended up changing out lots of other stuff and saw that my drive belt is tearing, bigger issue, will do that instead! Thanks!
