Intake Plenium
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I installed the plenum/TB after I already had an EVOMS GT700 + ICs. My butt dyno checked out at about 625 crank hp so subjectively I cannot tell any difference after the plenum/TB. However, I can measure a difference with my Performance Box and I feel the gains are worthwhile.
Somewhat surprizingly, I can measure improved performance at the low end and especially at the high end of the power range. The midrange is surprizingly unchanged or maybe even a touch lower than with the GT700 alone. Somewhat concerned about the midrange I contacted EVOMS about some custom tuning for the new plenum/TB. Todd Z said that no tuning was needed. The overall improvement for my car across the whole power band is roughly 4-5%. At my level that is roughly 25 hp which is a little more EVOMS claimed it would be. The TB/Plenum has only been on the car a week so the ECU may adapt and improve performance slowly. (After the GT700 kit had been on the car for three weeks the high rpm performance improved 2% without having done anything to the car and outside conditions had gotten even worse for engine power ie heat & humidity).
Here is a P Box plot of 4th gear during 60-130 runs. The plenum speed line is red the non plenum speed line is blue. If you download the chart and look at it closely you can see the plenum is slightly but definitively superior to the setup without the plenum. (Conditions are roughly equivalent ie both hot and humid!!) As you can see the plenum reaches 130 mph 0.13s faster than the nonplenum. This only tranlates into ~2ft of difference in distance traveled by each car during the run. The third gear performance is similar but slightly less difference between the two. Most of the gain is in the upper rpms which agrees with the IPD site for modded turbos. This may not seem like much unless you are interested in bettering your 60-130 time. The plenum/TB gave me roughly 0.1s improvement in third gear and a 0.13s improvement in fourth gear thus dropping a 60-130 time by more than 2 tenths.
So should you get this for your first mod on a stock turbo. The truth is I dont really know because I never had one one a stock turbo. But my judgement tells me this is probably not the best initial mod. I still believe a flash+DVs+/- sport exhaust is the place to start. The k-16s probably dont move enough air to benefit much from this mod, imo. I believe its is a worthwhile mod on higher hp cars to improve spool time and high rpm hp.
Somewhat surprizingly, I can measure improved performance at the low end and especially at the high end of the power range. The midrange is surprizingly unchanged or maybe even a touch lower than with the GT700 alone. Somewhat concerned about the midrange I contacted EVOMS about some custom tuning for the new plenum/TB. Todd Z said that no tuning was needed. The overall improvement for my car across the whole power band is roughly 4-5%. At my level that is roughly 25 hp which is a little more EVOMS claimed it would be. The TB/Plenum has only been on the car a week so the ECU may adapt and improve performance slowly. (After the GT700 kit had been on the car for three weeks the high rpm performance improved 2% without having done anything to the car and outside conditions had gotten even worse for engine power ie heat & humidity).
Here is a P Box plot of 4th gear during 60-130 runs. The plenum speed line is red the non plenum speed line is blue. If you download the chart and look at it closely you can see the plenum is slightly but definitively superior to the setup without the plenum. (Conditions are roughly equivalent ie both hot and humid!!) As you can see the plenum reaches 130 mph 0.13s faster than the nonplenum. This only tranlates into ~2ft of difference in distance traveled by each car during the run. The third gear performance is similar but slightly less difference between the two. Most of the gain is in the upper rpms which agrees with the IPD site for modded turbos. This may not seem like much unless you are interested in bettering your 60-130 time. The plenum/TB gave me roughly 0.1s improvement in third gear and a 0.13s improvement in fourth gear thus dropping a 60-130 time by more than 2 tenths.
So should you get this for your first mod on a stock turbo. The truth is I dont really know because I never had one one a stock turbo. But my judgement tells me this is probably not the best initial mod. I still believe a flash+DVs+/- sport exhaust is the place to start. The k-16s probably dont move enough air to benefit much from this mod, imo. I believe its is a worthwhile mod on higher hp cars to improve spool time and high rpm hp.
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Your mileage may vary however!!
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Yes, I can show with this third gear pull. Sorry I could not get software to line up speed plots exactly so just look at long G plots. The green one is the plenum/TB the black one is without plenum/TB. As you can see the plenum hits harder at 60-75ish then settles down then raises up again at 90-100mph.
Your mileage may vary however!!
Your mileage may vary however!!
I compared my 6.2 to my previous best of 6.61. From 60-100 are almost identical, but from 100-130 is obviously the .4 difference with the Meth...
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The new Y pipe design is in there somewhere, much bigger one for more flow. We are currently designing the new IC's way way larger than before. Let me just tell you that the heads move a lot of cfm's, lots more. Getting close for sure. I will have more updates next week. Cheers
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I did not realize you had those since they were not in your sig. What did Sharkey (assuming he is your tuner) tell you about the plenum/TB that made you want them?
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Plenum is pretty much one of the last things I could do to my car without going to bigger turbos (GT28s are as far as I wanted to go). As some of the posters mentioned, it is not the BBFYB but what can I say, I just want to try it. I asked Alex to order the plenum (70mm, works with stock TB) and installed it for me. He told me it should give me around 10-20 hp, but I should get better throttle response. Alex and James completed the install for me; my initial feeling was the car did feel quicker (maybe due to the quicker throttle resp.).
When Alex parted out his Great White (GT800), I was the first to jump on the Y-pipe since Alex knew I wanted it. The Y-pipe works with the 75mm TB and plenum, he bundled the whole thing and installed them for me.
I agree with others, this is not the first mod, or second, or third; but only the icing on the cake when you have a few bucks burning in your pockets.
When Alex parted out his Great White (GT800), I was the first to jump on the Y-pipe since Alex knew I wanted it. The Y-pipe works with the 75mm TB and plenum, he bundled the whole thing and installed them for me.
I agree with others, this is not the first mod, or second, or third; but only the icing on the cake when you have a few bucks burning in your pockets.
Last edited by MY996TT; Jul 19, 2009 at 11:11 PM.
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Very nice write up by Mbailey for sure and thanks for posting the data. It's obvious now that the car hits harder for sure. A measured performance and comparison is always the best metric to look at than dyno numbers. Like I always stand behind my words, the best mod I ever did.
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Very nice write up by Mbailey for sure and thanks for posting the data. It's obvious now that the car hits harder for sure. A measured performance and comparison is always the best metric to look at than dyno numbers. Like I always stand behind my words, the best mod I ever did.
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If you are refering to the pics on my thread, inlets 3" and inside 2" 5/8. TurboMike custom made one for me.
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Good Morning Everyone,
The IPD Intake Plenum is actually a fantastic initial option. The patented design will allow you to build boost faster, improve throttle response and increase horsepower. IPD Plenum's are guaranteed to increase power and torque and come with a 30 day money back guarantee.
Independent dyno testing on a stock 2002 996 TT Tiptronic showed consistent power gains throughout the entire power band with a max horsepower gain of 30-40 hp at the wheels.
Thanks
Ben@RSS
The IPD Intake Plenum is actually a fantastic initial option. The patented design will allow you to build boost faster, improve throttle response and increase horsepower. IPD Plenum's are guaranteed to increase power and torque and come with a 30 day money back guarantee.
Independent dyno testing on a stock 2002 996 TT Tiptronic showed consistent power gains throughout the entire power band with a max horsepower gain of 30-40 hp at the wheels.
Thanks
Ben@RSS
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Joined: Jul 2003
Posts: 2,957
From: Texas
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Good Morning Everyone,
The IPD Intake Plenum is actually a fantastic initial option. The patented design will allow you to build boost faster, improve throttle response and increase horsepower. IPD Plenum's are guaranteed to increase power and torque and come with a 30 day money back guarantee.
Independent dyno testing on a stock 2002 996 TT Tiptronic showed consistent power gains throughout the entire power band with a max horsepower gain of 30-40 hp at the wheels.
The IPD Intake Plenum is actually a fantastic initial option. The patented design will allow you to build boost faster, improve throttle response and increase horsepower. IPD Plenum's are guaranteed to increase power and torque and come with a 30 day money back guarantee.
Independent dyno testing on a stock 2002 996 TT Tiptronic showed consistent power gains throughout the entire power band with a max horsepower gain of 30-40 hp at the wheels.
Do you happen to have a dyno with a significantly modded turbo before and after the plenum?