Turbo surge with my APT 3071???
Have you ever plotted your PR and airflow points on the compressor map for this turbo to definitely see where the problem is?
That should give a real good picture if/when the surge is occuring at least.
Eric
That should give a real good picture if/when the surge is occuring at least.
Eric
Originally Posted by EVOVII_SWE
Hi Chris,
No it doesn't seam to make any difference at all to the surge, that together with the fact that spool up didn’t change at all either, I’m still seeing full boost around 3,5k, makes me think that perhaps I got just another .63
I’ve really looked outside and inside and found no marking at all on the new housing. That’s why I called Paul just after receiving it and he then told me that there is no a/r marking on the .82 housing and the reason were that they only have .63 and .82 EVO housings and no marking then tells you that it’s .82, sounds kind of strange to me when thinking more about it though?
If I lower boost between 3,5k-4,5k the surge is drastically reduced though, this of course gives a possibility to map “around” the problem so to speak as I can control boost both on rpm and gear with the Motec but I’m still puzzled that not more people are getting this problem?
No it doesn't seam to make any difference at all to the surge, that together with the fact that spool up didn’t change at all either, I’m still seeing full boost around 3,5k, makes me think that perhaps I got just another .63
I’ve really looked outside and inside and found no marking at all on the new housing. That’s why I called Paul just after receiving it and he then told me that there is no a/r marking on the .82 housing and the reason were that they only have .63 and .82 EVO housings and no marking then tells you that it’s .82, sounds kind of strange to me when thinking more about it though?If I lower boost between 3,5k-4,5k the surge is drastically reduced though, this of course gives a possibility to map “around” the problem so to speak as I can control boost both on rpm and gear with the Motec but I’m still puzzled that not more people are getting this problem?
so I took the liberty of remembering those figures, I remeber you asked me before. Ohya I have yet to have any surging problems with my 3071r with .63 ar housing. Ohya one more thing are you running both springs in the Tial wastegate?
Originally Posted by l2r99gst
Have you ever plotted your PR and airflow points on the compressor map for this turbo to definitely see where the problem is?
That should give a real good picture if/when the surge is occuring at least.
Eric
That should give a real good picture if/when the surge is occuring at least.
Eric
Well, to be honest I'm not that familiar with those maps, I saw that ATP recently put up the 3071R compressor and turbine maps but I don't really know how to read them
http://www.atpturbo.com/root/maps/gt3071r.htm
http://www.atpturbo.com/root/maps/gt3071rturbine.htm
And I have absolutely no idea how to plot my values on those either?
Originally Posted by Quickshift
Seems like you are still making the same boost at the same rpms. Maybe you got the .63 a/r again !! Has anything changed since you swapped the exhaust hosing in terms of the surge you where getting cause it seemed to be pretty severe ? What boost are you runing again and octane? And do you have any type of device to monitor knock properly (ie. knocklink) ? In fifth gear at 2700rpms I am hitting 7lbs of boost and by 3200rpm I am at 21psi. 4th gear I have boost at 7psi at 3000rpm flat and full about 3400 rpm. I was doing some test runs on my way back from school so I took the liberty of remembering those figures, I remeber you asked me before. Ohya I have yet to have any surging problems with my 3071r with .63 ar housing. Ohya one more thing are you running both springs in the Tial wastegate?
so I took the liberty of remembering those figures, I remeber you asked me before. Ohya I have yet to have any surging problems with my 3071r with .63 ar housing. Ohya one more thing are you running both springs in the Tial wastegate?I would certainly describe my surge as severe but I tried to lower the boost some now and the surge is drastically reduced or more or less gone by going down from about 24psi to 20psi at those specific rpms i.e. 3,5k-4,5k depending some on which gear I’m in. As I have the possibility to control boost based both on rpm and also which gear with the Motec I will have them to tune “around” the surge by reducing boost on 3’rd gear and up and at those rpms.
I have no knock device so I just have to trust that they do the tuning properly.
I’ve been running around 24-25psi on 98 octane (RON) which should be around 92-93 octane in your standard if I’m not mistaking. And I’m running two springs in the waste gate, big red and small yellow. Used to have a small blue but changed to a yellow to be able to lower boost to avoid surge during the next tuning session.
I think I have very similar boost behaviour to your car, I also have around 21psi at 3,300rpm or there about in 5th gear.
24psi on 92 oct is kind of scary , but you got a great ecu to control it. The .82 a/r housing should have created more lag. I am thinking you have the wrong housing man. When does the surging occur rpm wise?
Originally Posted by EVOVII_SWE
Yes, as far as I can tell without any scientific testing, same boost at about the same rpms. I spoke to ATP yesterday and they are sure that I have the .82 housing now as those lack a/r markings and the .63 doesn’t and those are the only two turbine housings they have for the EVO.
I would certainly describe my surge as severe but I tried to lower the boost some now and the surge is drastically reduced or more or less gone by going down from about 24psi to 20psi at those specific rpms i.e. 3,5k-4,5k depending some on which gear I’m in. As I have the possibility to control boost based both on rpm and also which gear with the Motec I will have them to tune “around” the surge by reducing boost on 3’rd gear and up and at those rpms.
I have no knock device so I just have to trust that they do the tuning properly.
I’ve been running around 24-25psi on 98 octane (RON) which should be around 92-93 octane in your standard if I’m not mistaking. And I’m running two springs in the waste gate, big red and small yellow. Used to have a small blue but changed to a yellow to be able to lower boost to avoid surge during the next tuning session.
I think I have very similar boost behaviour to your car, I also have around 21psi at 3,300rpm or there about in 5th gear.
I would certainly describe my surge as severe but I tried to lower the boost some now and the surge is drastically reduced or more or less gone by going down from about 24psi to 20psi at those specific rpms i.e. 3,5k-4,5k depending some on which gear I’m in. As I have the possibility to control boost based both on rpm and also which gear with the Motec I will have them to tune “around” the surge by reducing boost on 3’rd gear and up and at those rpms.
I have no knock device so I just have to trust that they do the tuning properly.
I’ve been running around 24-25psi on 98 octane (RON) which should be around 92-93 octane in your standard if I’m not mistaking. And I’m running two springs in the waste gate, big red and small yellow. Used to have a small blue but changed to a yellow to be able to lower boost to avoid surge during the next tuning session.
I think I have very similar boost behaviour to your car, I also have around 21psi at 3,300rpm or there about in 5th gear.
Originally Posted by Quickshift
24psi on 92 oct is kind of scary , but you got a great ecu to control it. The .82 a/r housing should have created more lag. I am thinking you have the wrong housing man. When does the surging occur rpm wise?
The surging starts to be noticeable from 3rd gear and up and the higher the gear the worse it gets as the load increases. Surge is at its peak around 4k and spans between about 3,5k-4,5k rpms.
Originally Posted by EVOVII_SWE
Hi Eric,
Well, to be honest I'm not that familiar with those maps, I saw that ATP recently put up the 3071R compressor and turbine maps but I don't really know how to read them
http://www.atpturbo.com/root/maps/gt3071r.htm
http://www.atpturbo.com/root/maps/gt3071rturbine.htm
And I have absolutely no idea how to plot my values on those either?
Well, to be honest I'm not that familiar with those maps, I saw that ATP recently put up the 3071R compressor and turbine maps but I don't really know how to read them
http://www.atpturbo.com/root/maps/gt3071r.htm
http://www.atpturbo.com/root/maps/gt3071rturbine.htm
And I have absolutely no idea how to plot my values on those either?
If you have this data for a run, you just plot the points of the compressor map. This will tell you if you really are surging and where the problem is occurring.
I can do it for you, but I need some data from one of the runs that you were experiencing the problem. I need at least airflow (lb/min, g/s, or whatever) and either boost or airflow/rev and approximate temperature.
Eric
Originally Posted by altrix99
Here are approximate points on the map at a given rpm and boost level...
Chris
Newbie
Joined: Feb 2004
Posts: 61
Likes: 1
Originally Posted by 2k4EvoVIII
Thats a cool find. They got one on the GT35/40R? Also dont forget Thomas that you had another issue that could have been making your car run bad "CAS sensor" so after you fixed that and put this new housing on it could feel the same becouse you gained HP from the CAS being on right now and not 180 degrees off. I could be wrong but just a thought??
Chris
Chris
GT35R coming up shortly...
Last edited by altrix99; Oct 5, 2004 at 08:28 AM.
Evolving Member
Joined: May 2003
Posts: 300
Likes: 0
From: Arizona
http://www.mygen.com/users/dbruce/my...sor%20Maps.htm
First thing that popped up on google. Stuff like this may be worth a read to get a good grip on what may be going on and why.
First thing that popped up on google. Stuff like this may be worth a read to get a good grip on what may be going on and why.
Originally Posted by altrix99
Again, based on 85% VE
Don't believe the GT35/40R nomenclature. All of them are just GT35R's. GT35/40R is a marketing gimmick. Just sounds cooler...
Chris