Aux port tuning for turbo
#29
Administrator
dont you also have the issue of timing the opening in the intake with the opening of the actual port as the rotor sweeps past? Mazda has timed them to open when the port actually opens. if you open them when the port is closed or closing that cant be good.
#35
Administrator
no seriously in NA form because of the helmholtz tuning the intake openings are timed with the actual port openings so you dont get bad resonance waves from the air "hitting" the closed port. but as i said im just tired- the FI makes it moot.
#40
![Thumbs up](https://www.rx8club.com/images/icons/icon14.gif)
check out the blue line - wow what a difference .....
![](https://i154.photobucket.com/albums/s255/brettus_rx8/porttuning.jpg)
bit of a bummer losing traction at 6000 rpm in 2nd gear but i'll get over it![Eyetwitch](https://www.rx8club.com/images/smilies/eyetwitch.gif)
EDIT: light blue line was in 2nd gear ...this wouldn't have happened like that if I'd done same test in 3rd !
![](https://i154.photobucket.com/albums/s255/brettus_rx8/porttuning.jpg)
bit of a bummer losing traction at 6000 rpm in 2nd gear but i'll get over it
![Eyetwitch](https://www.rx8club.com/images/smilies/eyetwitch.gif)
EDIT: light blue line was in 2nd gear ...this wouldn't have happened like that if I'd done same test in 3rd !
Last edited by Brettus; 01-16-2022 at 04:55 PM.
#41
13B-RE
iTrader: (1)
^
Is that light blue line is no APV opening at all or is it open completely the whole time? From your graph it almost seems like the right point to open the APV is at around 7000 and not 6100. Interesting.... did you try opening the APV latter than stock?
Thanks and good luck.
Chris
Is that light blue line is no APV opening at all or is it open completely the whole time? From your graph it almost seems like the right point to open the APV is at around 7000 and not 6100. Interesting.... did you try opening the APV latter than stock?
Thanks and good luck.
Chris
Last edited by ChrisRX8PR; 01-12-2009 at 01:29 PM.
#42
blue line is no apv or vdi at all .
This has made a huge difference to my setup and I think all Greddy turbo owners should run like this .
Opening the apv later will allow more flow but it will also take me well outside the efficiency curve .
This was at 9psi (UIM) 10psi (turbo) all the way to 7500 which also means i'm not far out of the efficiency curve for my turbo - evidenced by the steady IATs .
This has made a huge difference to my setup and I think all Greddy turbo owners should run like this .
Opening the apv later will allow more flow but it will also take me well outside the efficiency curve .
This was at 9psi (UIM) 10psi (turbo) all the way to 7500 which also means i'm not far out of the efficiency curve for my turbo - evidenced by the steady IATs .
Last edited by Brettus; 01-12-2009 at 01:36 PM.
#43
13B-RE
iTrader: (1)
blue line is no apv or vdi at all .
This has made a huge difference to my setup and I think all Greddy turbo owners should run like this .
Opening the apv later will allow more flow but it will also take me well outside the efficiency curve .
This was at 9psi (UIM) 10psi (turbo) all the way to 7500 which also means i'm not far out of the efficiency curve for my turbo - evidenced by the steady IATs .
This has made a huge difference to my setup and I think all Greddy turbo owners should run like this .
Opening the apv later will allow more flow but it will also take me well outside the efficiency curve .
This was at 9psi (UIM) 10psi (turbo) all the way to 7500 which also means i'm not far out of the efficiency curve for my turbo - evidenced by the steady IATs .
Great work by the way.
Chris
#45
13B-RE
iTrader: (1)
I'd keep it closed if I were you, that is probably the reason Greddy sold their kit with a block off plate. Interesting...
Best regards,
Chris
#46
yes mm commented earlier that he was opening the port later than stock - I can see why now .
Yes the blocking plate - seems like Greddy knew what they were doing with that . A lot of people who didn't fit it are not only losing power but also over extending their turbos ....
Yes the blocking plate - seems like Greddy knew what they were doing with that . A lot of people who didn't fit it are not only losing power but also over extending their turbos ....
#47
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The amount of boost being run on this forum is not enough to change the resonance in the runners more then a few percent... therefore only change the timing if your having tuning issues (and then solve those issues in other ways)
#48
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It seems your statement would indicate both, if you would care to elaborate that would be great...
And is the 'recalibration' snappier - quicker, or more gradual allowing boost to come smoother at WOT...
And what are your thoughts of why this is important for you, amount of sudden boost? traction? etc? etc?