IPD Plenum Day Dyno Results (with Pictures)
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Greg at RSS had also told me that he was planning to dyno the larger throttle body for the 996 with the Plenum. For those that were there, do you know if that happened? I'm curious as the two pieces together should get more airflow to the engine.
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It won't get more air to the engine but will change the velocity of the air which will effect power curve.
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For the nay sayers that feel there can be no benifit in modifying a Porsche engine and that Porsche have allready maxed it out as i read in a previous post .
bull....
I have a 3.4 ltr with a exhaust from starr performance with a 70mm intake pipe with a BMC CDA air cleaner,
i have also fitted it with a pair of shrick cams as well as a lightenned fly wheel.
the car makes 196kw at the rear wheels while a stock 996 makes 166kw at rw and a series 2 3.6 makes 174kw at rw
Although i have not yet tried the plenium as im waiting to find the australian agents or become one, it is obvious that a ram tube flows more air than a straight piece of pipe and the same principal will apply here.
bull....
I have a 3.4 ltr with a exhaust from starr performance with a 70mm intake pipe with a BMC CDA air cleaner,
i have also fitted it with a pair of shrick cams as well as a lightenned fly wheel.
the car makes 196kw at the rear wheels while a stock 996 makes 166kw at rw and a series 2 3.6 makes 174kw at rw
Although i have not yet tried the plenium as im waiting to find the australian agents or become one, it is obvious that a ram tube flows more air than a straight piece of pipe and the same principal will apply here.
174KW = 233 HP
196KW = 266 HP
what kind of dyno are you using... those numbers seem low
also... how much low end power are you losing with the shrick camshafts?
cheers
P.
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C70pete hi from australia ,
we have also found that your dynos seem a little optimistic however i can assure you that the numbers are correct.
i beleive that we use a different set of values here . but the start point of 166kw is valid and thereby the numbers are a valid gain in performance.
i personally would not complain about the bottom end torque as i can drive around in 6th gear at 1600rpm and it just accelerates away no stress at all and will pullup steep hill in 6th as well with no labourering.
the car has run a 4.6 to 100kph /60mph and a 12.6 qtr
the point i was trying to make was that it is easy to pick up hp in these engines .
you stateside guys should have a look at starr performance over here .i have seen most of the big name headers and i wouldnt fit them on my mower let alone my porsche
greg
we have also found that your dynos seem a little optimistic however i can assure you that the numbers are correct.
i beleive that we use a different set of values here . but the start point of 166kw is valid and thereby the numbers are a valid gain in performance.
i personally would not complain about the bottom end torque as i can drive around in 6th gear at 1600rpm and it just accelerates away no stress at all and will pullup steep hill in 6th as well with no labourering.
the car has run a 4.6 to 100kph /60mph and a 12.6 qtr
the point i was trying to make was that it is easy to pick up hp in these engines .
you stateside guys should have a look at starr performance over here .i have seen most of the big name headers and i wouldnt fit them on my mower let alone my porsche
greg
Last edited by BOX3.4LTR; Jun 4, 2008 at 01:30 AM.
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So, did the dyno operator inform everyone that you automatically pick up some added power when you reset the computer.....AND NO OTHER CHANGES HAVE BEEN MADE or did they leave that little bit of info out and just reset the computer AFTER the new plenum was installed? 
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I'm agnostic when it comes to believe in the Plenum. What I'm wondering is if someone has addressed the previously raised issue of coolant temperature playing a role in the power produced on the dyno. Was anything done to confirm the conditions (including temperatures) were the same for the before and after runs?
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I'm agnostic when it comes to believe in the Plenum. What I'm wondering is if someone has addressed the previously raised issue of coolant temperature playing a role in the power produced on the dyno. Was anything done to confirm the conditions (including temperatures) were the same for the before and after runs?
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Guys, it shifts the power curve a bit, but you're not gaining any peak HP. SO in essence, you don't get anything without increasing oxygen into the engine itself via forced induction. this is what 1999 is saying.
I avoid any engine mods aside from noise on a normally aspirated car. why? it doesn't do jack for making your car go faster in a straight line.
there is no free lunch. if you want mad power, just get a car that comes with more power, make your car lighter, add forced induction... a little part isn't going to make your car faster than stock because porsche already maxed it out.
so let's not make it a religious or personal war here. i, for one, would never spend money on the plenum.
I avoid any engine mods aside from noise on a normally aspirated car. why? it doesn't do jack for making your car go faster in a straight line.
there is no free lunch. if you want mad power, just get a car that comes with more power, make your car lighter, add forced induction... a little part isn't going to make your car faster than stock because porsche already maxed it out.
so let's not make it a religious or personal war here. i, for one, would never spend money on the plenum.
-Eli
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Amazingly I am in full agreement here. Resetting the ECU and clearing the fuel trim adaptation always bumps the power. This was a trick we used to see with E36M3 tuners pushing software or suboptimal intake parts. The test validity is questionable unless you reset the ECU on a stock car, dyno it, install the xxx part then reset the ECU and then dyno again.
The stock test should have been performed in the same manner as it was stated it would be done......
-Eli
BY THE WAY, ANYONE WHAT TO SELL ME THEIR STOCK UNIT? I THINK I MIGHT RUN A CAST MOLD WITH BRASS FITTINGS, PORT AND POLISH.... POSSIBLE MATCH PORT TO GO ALONG MIGHT HAVE A BETTER END RESULT. I HAVE MOST OF THE TOOLS NEEDED, MIGHT AS WELL TRY TO PUT SOMETHING TOGETHER FOR THE HECK OF IT....
IF ANYONE IS WILLING TO DONATE THIS ITEM I'LL DONATE THE NEW ITEM WHEN FINISHED AT "COST" +10....
Last edited by Wheel Dynamics; Jun 4, 2008 at 12:59 PM.
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Has anyone tried running quarter mile times or 0-60 times on a pcar with / without the plenum?
Would be interesting to see if the runs are consistently faster with the plenum installed than with it removed / stock. +20hp should equal a slightly faster run no?
Would be interesting to see if the runs are consistently faster with the plenum installed than with it removed / stock. +20hp should equal a slightly faster run no?
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you know what the final test should've been?
youtube a pre-plenum run v. a baseline car..... so a stock v. stock run of a 911.
then post plenum, run the same cars from a slow rolling start to whatever MPH and keep doing this.
youtube a pre-plenum run v. a baseline car..... so a stock v. stock run of a 911.
then post plenum, run the same cars from a slow rolling start to whatever MPH and keep doing this.