plenum
#16
I have 74mm and IPD Plenum I make 852nm RW Torque with standard turbos I also have an IPD on my supercharged boxster I think its a good mod but also think about coils and a pulley. My pulley is one of my favourite mods. Go with it as it will only help future mods.
#18
Hello,
I just received the IPD plenum,but it is without check valve ,on their site you can see a check valve please see the attached picture.(the black and yellow)do i have to install one?
I just received the IPD plenum,but it is without check valve ,on their site you can see a check valve please see the attached picture.(the black and yellow)do i have to install one?
#19
NO,,It should come with one..
#20
Sorry there is a check valve ,a straight one not 90 degrees,i thought it just a connector.I installed the plenum and the TB,i drove the car ,its much responsive and hit the boost earlier.
#21
By any chance did you see my recent thread on my swap on the dyno?
My gas mileage stayed the same at Steady cruising but if I get on the car in part throttle ranges, in city driving, then it suffers...
#23
John would you care to post a picture of your actual unit, I would be very interested in seeing what it looks like.
The Check valve is not the 90deg brake booster style anymore, the white one is a quality item.
#25
Also that was the same valve I had when I did a dyno test way back when on the stock TB size one..
Thanks..
#26
OH so I just went and read your entire thread about your Modified IDP plenum....
So if I get it straight you cut the back out of it and made it a T not a Y like it was designed to be. Whoever did that really does not understand the idea of flow dynamics.... Have you ever seen a performance intake port or header that slams the incoming or outgoing charge into a flat wall.
I bet you also used aluminum with a smooth surface finish.
The IDP plenum sure looks like it would do a great job of directing flow, and the rough cast surface inside should also do a good job of separating the surface layer of air around the corners. Breaking that boundary layer of flow is a very small detail in terms of performance on a 500+ hp car that is force inducted but it is a detail none the less. All the small details, good or bad, do eventually make a difference when multiplied.
From what I have seen of many tuners stuff in the P car world is they do not get the principle of boundary layer separation and air flow dynamics.
The engine is out of my car right now and coincidentally an IDP plenum was installed. The first thing I thought when I seen the inside of my intake piping was (Yup, gonna sand blast the inside of this stuff when I get home"
If you want to see a good example of boundary layer separation in practise look at an Olympic bobsleigh and its occupants. They put that sandy grip tape on the outside of the sled in certain spots and on top of their helmets; why, all to decrease boundary layer drag.
#27
Sorry John that point was not in relation to any of your statements, that was a comment about one of the other guys mentioning he had a white connector.
Sadly to say I am not going to have a way to test the plenum only in my car as a bunch of other items were all done at the same time. But from a sound engineering point I know the item is a better design then factory. I also asked all the guys from BBI and another shop if they have seen direct testing of the part; all said the item noticeably worked on both the dyno and the butt dyno.
John do you care to post a pic of your plenum, I would be curious to see it and know who modified and why????
#28
OH so I just went and read your entire thread about your Modified IDP plenum....
So if I get it straight you cut the back out of it and made it a T not a Y like it was designed to be. Whoever did that really does not understand the idea of flow dynamics.... Have you ever seen a performance intake port or header that slams the incoming or outgoing charge into a flat wall.
I bet you also used aluminum with a smooth surface finish.
The IDP plenum sure looks like it would do a great job of directing flow, and the rough cast surface inside should also do a good job of separating the surface layer of air around the corners. Breaking that boundary layer of flow is a very small detail in terms of performance on a 500+ hp car that is force inducted but it is a detail none the less. All the small details, good or bad, do eventually make a difference when multiplied.
From what I have seen of many tuners stuff in the P car world is they do not get the principle of boundary layer separation and air flow dynamics.
The engine is out of my car right now and coincidentally an IDP plenum was installed. The first thing I thought when I seen the inside of my intake piping was (Yup, gonna sand blast the inside of this stuff when I get home"
If you want to see a good example of boundary layer separation in practise look at an Olympic bobsleigh and its occupants. They put that sandy grip tape on the outside of the sled in certain spots and on top of their helmets; why, all to decrease boundary layer drag.
Also it was flowed with the 74 TB on it and so was a IPD PLENUM, non modified, with the same TB on a Superflow bench..OUR Findings,, Modified one flowed more on our test.
I BELIEVE the 74TB is the major difference in performance.
I HAVE built , tuned, designed parts and been around for many years BUT not in this Porsche area BUT as we all know real world is the truth Not theory as I HAVE proven in my past testing in my area.
ITS ALL GOOD, SHARING AND LEARNING.
#29
Also, I did back to back tests on the Dyno which I still have the sheets on a stock 68 TB one compared to the stock Porsche plenum..
On my combo lets just say again, theory is not real world..I put the stock one back on AND got a refund on the IPD.
ALSO, we are talking on these results WOT AND TOTAL flow, not part throttle comparisons.
As I used and kept IPD plenums on all my past non turbo cars.
On my combo lets just say again, theory is not real world..I put the stock one back on AND got a refund on the IPD.
ALSO, we are talking on these results WOT AND TOTAL flow, not part throttle comparisons.
As I used and kept IPD plenums on all my past non turbo cars.
#30
Sorry to continue this but I thought I would add one more tid bit here..
On our flow bench test...The air didnt like it when the throttle blade was wide open with the splitter being that close to it...It caused tubulance,as compared to no splitter, making the far side air bend into one of the opposite leg of the plenum..
You could say ,will it is under pressure anyways,then you can say the same about not needing a splitter??..
If I had the time and wanted to buy that other IPD plenum,,I would have welded the backside of it where the V was and ground down some of that center splitter to have a better turning radius fo the TB..
Would all of this mattered?? Who knows ?..I believe the TB size did matter..
I do feel a more sensitive gas pedal and better throttle response and it hitting harder in the higher RPMS..The resaon bigger TB??
That front short side radius of the IPD is alot nicer then any other plenum I ever saw.
I am done here...Just sharing what I learned and I did...
Also,Thanks again Tim NYC..And Turbo Mike does make a good product and he is also a good guy >>
As they say ,,Results may vary, especially due to mods ..LOL..
On our flow bench test...The air didnt like it when the throttle blade was wide open with the splitter being that close to it...It caused tubulance,as compared to no splitter, making the far side air bend into one of the opposite leg of the plenum..
You could say ,will it is under pressure anyways,then you can say the same about not needing a splitter??..
If I had the time and wanted to buy that other IPD plenum,,I would have welded the backside of it where the V was and ground down some of that center splitter to have a better turning radius fo the TB..
Would all of this mattered?? Who knows ?..I believe the TB size did matter..
I do feel a more sensitive gas pedal and better throttle response and it hitting harder in the higher RPMS..The resaon bigger TB??
That front short side radius of the IPD is alot nicer then any other plenum I ever saw.
I am done here...Just sharing what I learned and I did...
Also,Thanks again Tim NYC..And Turbo Mike does make a good product and he is also a good guy >>
As they say ,,Results may vary, especially due to mods ..LOL..
Last edited by johnspeed; 08-18-2012 at 01:11 PM.