Official STS Rear Mount Turbo Discussion Thread
#1721
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idk if this has been mentioned but...
i have aftermarket testpipe with resonators and the rest of the exhaust was stock so i just got back and had the big *** resonator cut out near the turbo and replaced with a straight pipe and heres the results
loud as ****(given) but im on a manual boost controller and only on 5psi right now till i get tuned so before i wasnt hitting any boost in 1st but now after this im hitting 1-2psi in first!
so next is getting un resonated test pipes then fiberglass rapping the whole exhaust i also have a ebc installed just not the solenoid so after thats installed im getting tuned and ill let you guys know those results
sorry for the run on sentences im excited and im also pooping =)
i have aftermarket testpipe with resonators and the rest of the exhaust was stock so i just got back and had the big *** resonator cut out near the turbo and replaced with a straight pipe and heres the results
loud as ****(given) but im on a manual boost controller and only on 5psi right now till i get tuned so before i wasnt hitting any boost in 1st but now after this im hitting 1-2psi in first!
so next is getting un resonated test pipes then fiberglass rapping the whole exhaust i also have a ebc installed just not the solenoid so after thats installed im getting tuned and ill let you guys know those results
sorry for the run on sentences im excited and im also pooping =)
#1722
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idk if this has been mentioned but...
i have aftermarket testpipe with resonators and the rest of the exhaust was stock so i just got back and had the big *** resonator cut out near the turbo and replaced with a straight pipe and heres the results
loud as ****(given) but im on a manual boost controller and only on 5psi right now till i get tuned so before i wasnt hitting any boost in 1st but now after this im hitting 1-2psi in first!
so next is getting un resonated test pipes then fiberglass rapping the whole exhaust i also have a ebc installed just not the solenoid so after thats installed im getting tuned and ill let you guys know those results
sorry for the run on sentences im excited and im also pooping =)
i have aftermarket testpipe with resonators and the rest of the exhaust was stock so i just got back and had the big *** resonator cut out near the turbo and replaced with a straight pipe and heres the results
loud as ****(given) but im on a manual boost controller and only on 5psi right now till i get tuned so before i wasnt hitting any boost in 1st but now after this im hitting 1-2psi in first!
so next is getting un resonated test pipes then fiberglass rapping the whole exhaust i also have a ebc installed just not the solenoid so after thats installed im getting tuned and ill let you guys know those results
sorry for the run on sentences im excited and im also pooping =)
So you removed the resonator from the mid-pipe? Otherwise, I don't know what resonator your talking about, unless it's a G?
What kind of resonated test pipes are they? I'm actually looking to buy some, and them I'm replacing the stock resonator on the mid-pipe with the Magnaflow one, since right now it's just too loud.
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lol
So you removed the resonator from the mid-pipe? Otherwise, I don't know what resonator your talking about, unless it's a G?
What kind of resonated test pipes are they? I'm actually looking to buy some, and them I'm replacing the stock resonator on the mid-pipe with the Magnaflow one, since right now it's just too loud.
So you removed the resonator from the mid-pipe? Otherwise, I don't know what resonator your talking about, unless it's a G?
What kind of resonated test pipes are they? I'm actually looking to buy some, and them I'm replacing the stock resonator on the mid-pipe with the Magnaflow one, since right now it's just too loud.
theyre kinetix test pipes so let me know and yes its a g
#1724
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post vids and dyno results please. I was going to go Built powerlab but i think instead im going STS bc of sound and price. Im gonna buy a house with the remainder 20K i was quoted by other shops. And def letting Bobby at CIN do it all. Only person i like touching my car. i remember a while back when a few local guys were getting this they said they were making better or same power level with stock parts like exhaust and cats compared to test pipes and aftermarket y pipe etc.
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The very first set up on my sts build was with the mid pipe resonator taken out, and when i went to pick up the car, we took it out on the road so boby could see how it was running and go over the car with me. I told him before the car was finished, i didn't care how loud it was, which is why the resonator was taken out. Well, as soon as we got back to the shop after that first drive, we were wutting the exhaust to put the resonator back it. The car sounded HORRIBLE. It literally sounded like a pack of angry honda civic's. It was obnoxious. I didn't care about how loud it was, but the sound was just bad. I don't know if its because i was running test pipes already, or if it was from the 3.8L motor, or what, but it did not sound good. If you car sounds like what mine did, i would say put the resonator back in. My car is stil plenty loud, enough to **** over every neighbor for like 2 blocks, but in my opinion, it still sounds good. Still has that Z sound, with a jet motor attached. You really aren't going to gain much power from removing that resonator, but you will pick up A LOT of rasp and cracking in the exhaust note. If your going to go with Test pipes, leave the resonator in, it cleans up the exhaust sound SOOOOO much. Just my opinion and recommendation, of course its your car. If you like the sound, go with it, just letting you know my thoughts of it from my experience. Defnitely post some video, and get a decent camera that can capture the true sound, its soo damn hard to find a camera that picks up the whine of the turbo.
#1726
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Well, I still have my idle issues. I did the three reset procedures, resetting the acc pedal, throttle, and idle air volume. However, on the throttle reset, the manual says that you turn the ign ON, then turn it OFF for 10 secs, and you should hear the throttle cycle after that. I didn't hear anything though. I tried it twice. I went through the idle air volume reset successfully though.
I'm running the -9 psi spring on the BOV, but it seems to make the situation worse. It helps a ton with compressor surge, but it opens up at idle which seems to make the car idle worse.
I swapped back in the -11 psi spring, and it seemed to help. It stays completely closed at idle. However, there is definitely some compressor surge.
Now I'm back with the -9 psi spring. The BOV keeps fluctuating open and closed at idle. I can't figure out if it's sucking in air, or releasing air when it's open. I put a plastic bag around it and it wasn't sucking in, but it wasn't puffing up either. Ughh. According to my UTEC i'm pulling -10 psi - is that about average?
Here are a few videos. In both cases, the idle wasn't as bad as it usually is. It usually stumbles real hard, or stalls.
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So what do you guys think it could be?
1. Vacuum leak, although I used a hose to my ear and poked all around and didn't find anything
2. Just a low idle, and this will be resolved if I bump the idle to 1k rpms
3. Bad/dirty MAF?
Btw, my AFR is good at idle (14.5-15.5), but leans out at times (sometimes as high as 19 ??) when it starts stumbling.
I'm thinking of just giving up for now until I install bigger injectors and possibly a fuel return. Hopefully it's just a plenum vacuum leak, and it will fix itself when I re-install it.
I'm running the -9 psi spring on the BOV, but it seems to make the situation worse. It helps a ton with compressor surge, but it opens up at idle which seems to make the car idle worse.
I swapped back in the -11 psi spring, and it seemed to help. It stays completely closed at idle. However, there is definitely some compressor surge.
Now I'm back with the -9 psi spring. The BOV keeps fluctuating open and closed at idle. I can't figure out if it's sucking in air, or releasing air when it's open. I put a plastic bag around it and it wasn't sucking in, but it wasn't puffing up either. Ughh. According to my UTEC i'm pulling -10 psi - is that about average?
Here are a few videos. In both cases, the idle wasn't as bad as it usually is. It usually stumbles real hard, or stalls.
<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/OBhA4cnKsYg&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/OBhA4cnKsYg&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>
<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/8rGwvWaxcAk&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/8rGwvWaxcAk&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>
So what do you guys think it could be?
1. Vacuum leak, although I used a hose to my ear and poked all around and didn't find anything
2. Just a low idle, and this will be resolved if I bump the idle to 1k rpms
3. Bad/dirty MAF?
Btw, my AFR is good at idle (14.5-15.5), but leans out at times (sometimes as high as 19 ??) when it starts stumbling.
I'm thinking of just giving up for now until I install bigger injectors and possibly a fuel return. Hopefully it's just a plenum vacuum leak, and it will fix itself when I re-install it.
#1727
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The very first set up on my sts build was with the mid pipe resonator taken out, and when i went to pick up the car, we took it out on the road so boby could see how it was running and go over the car with me. I told him before the car was finished, i didn't care how loud it was, which is why the resonator was taken out. Well, as soon as we got back to the shop after that first drive, we were wutting the exhaust to put the resonator back it. The car sounded HORRIBLE. It literally sounded like a pack of angry honda civic's. It was obnoxious. I didn't care about how loud it was, but the sound was just bad. I don't know if its because i was running test pipes already, or if it was from the 3.8L motor, or what, but it did not sound good. If you car sounds like what mine did, i would say put the resonator back in. My car is stil plenty loud, enough to **** over every neighbor for like 2 blocks, but in my opinion, it still sounds good. Still has that Z sound, with a jet motor attached. You really aren't going to gain much power from removing that resonator, but you will pick up A LOT of rasp and cracking in the exhaust note. If your going to go with Test pipes, leave the resonator in, it cleans up the exhaust sound SOOOOO much. Just my opinion and recommendation, of course its your car. If you like the sound, go with it, just letting you know my thoughts of it from my experience. Defnitely post some video, and get a decent camera that can capture the true sound, its soo damn hard to find a camera that picks up the whine of the turbo.
i have test pipes already just resonated. the sound is def ridiculously loud but it still sounded good a little raspy in the car but when i was out of the car and heard it it sounded so different but in a good way
#1728
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The very first set up on my sts build was with the mid pipe resonator taken out, and when i went to pick up the car, we took it out on the road so boby could see how it was running and go over the car with me. I told him before the car was finished, i didn't care how loud it was, which is why the resonator was taken out. Well, as soon as we got back to the shop after that first drive, we were wutting the exhaust to put the resonator back it. The car sounded HORRIBLE. It literally sounded like a pack of angry honda civic's. It was obnoxious. I didn't care about how loud it was, but the sound was just bad. I don't know if its because i was running test pipes already, or if it was from the 3.8L motor, or what, but it did not sound good. If you car sounds like what mine did, i would say put the resonator back in. My car is stil plenty loud, enough to **** over every neighbor for like 2 blocks, but in my opinion, it still sounds good. Still has that Z sound, with a jet motor attached. You really aren't going to gain much power from removing that resonator, but you will pick up A LOT of rasp and cracking in the exhaust note. If your going to go with Test pipes, leave the resonator in, it cleans up the exhaust sound SOOOOO much. Just my opinion and recommendation, of course its your car. If you like the sound, go with it, just letting you know my thoughts of it from my experience. Defnitely post some video, and get a decent camera that can capture the true sound, its soo damn hard to find a camera that picks up the whine of the turbo.
#1729
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Unless you are upgrading the turbo, you'll want to stick with 2.5" or smaller. Anything bigger will increase the spool time, at least according to people on here. I think I'm going with 2.25" TPs. Actually, goosegoose is pushing something like 600hp and he's only going with 2.5".
#1730
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So what do you guys think it could be?
1. Vacuum leak, although I used a hose to my ear and poked all around and didn't find anything
2. Just a low idle, and this will be resolved if I bump the idle to 1k rpms
3. Bad/dirty MAF?
Btw, my AFR is good at idle (14.5-15.5), but leans out at times (sometimes as high as 19 ??) when it starts stumbling.
I'm thinking of just giving up for now until I install bigger injectors and possibly a fuel return. Hopefully it's just a plenum vacuum leak, and it will fix itself when I re-install it.
My conclusion on the MAF sensor was that the way that STS put the MAF bung into the intake pipe from the intercooler outlet is different from the stock MAF housing. The MAF sensor is set up to read a certain flow rate with the sensor enclosed in the stock MAF housing. So the stock computer thinks it is getting one flow rate and adjusts the pulse width signal to the injectors or whatever accordingly. Then when the AFR's go nuts because the mixture is wrong, the stock computer tries to correct and it starts the cycle all over.
So the only way to test this theory is to somehow put the stock MAF housing back into the system. I think this is why the Greddy kit still uses the stock MAF housing.
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^ Well that's not good news. It does seem to be very cyclical, as if it keeps over-correcting each way. I guess it would be good for me to watch the log of the MAF voltage to see if it's fluctuating. I wonder if you can see the actual % throttle as well (not the throttle of the driver)? Maybe only with the Cipher scan tool.
My friend has a Consult II, so I'm going to try bumping the idle to see what happens.
I have to say though, with the BOV open at idle, I'm a little worried about unfiltered air getting in there. I still can't determine if it's sucking it in though. Oooo, I need to get a flashlight and some type of smoke (cigarettes maybe?). No one else seems to have their BOV open partially at idle though, but not many people are running lower than the -11 psi spring.
EDIT: Maybe I should just stick with the -11 psi spring and not worry so much. With my vacuum reading at idle, the -11 psi spring is the right one according to TiAL.
My friend has a Consult II, so I'm going to try bumping the idle to see what happens.
I have to say though, with the BOV open at idle, I'm a little worried about unfiltered air getting in there. I still can't determine if it's sucking it in though. Oooo, I need to get a flashlight and some type of smoke (cigarettes maybe?). No one else seems to have their BOV open partially at idle though, but not many people are running lower than the -11 psi spring.
EDIT: Maybe I should just stick with the -11 psi spring and not worry so much. With my vacuum reading at idle, the -11 psi spring is the right one according to TiAL.
Last edited by JonnyC; 03-16-2009 at 07:28 PM.
#1733
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^ Well that's not good news. It does seem to be very cyclical, as if it keeps over-correcting each way. I guess it would be good for me to watch the log of the MAF voltage to see if it's fluctuating. I wonder if you can see the actual % throttle as well (not the throttle of the driver)? Maybe only with the Cipher scan tool.
My friend has a Consult II, so I'm going to try bumping the idle to see what happens.
I have to say though, with the BOV open at idle, I'm a little worried about unfiltered air getting in there. I still can't determine if it's sucking it in though. Oooo, I need to get a flashlight and some type of smoke (cigarettes maybe?). No one else seems to have their BOV open partially at idle though, but not many people are running lower than the -11 psi spring.
My friend has a Consult II, so I'm going to try bumping the idle to see what happens.
I have to say though, with the BOV open at idle, I'm a little worried about unfiltered air getting in there. I still can't determine if it's sucking it in though. Oooo, I need to get a flashlight and some type of smoke (cigarettes maybe?). No one else seems to have their BOV open partially at idle though, but not many people are running lower than the -11 psi spring.
What about trimming the spring to stiffen it up? Or putting spacers on the stock spring to increase compression a bit? I can't remember if we talked about this before...
The MAF housing could easily be rigged into place by a semi competent fabricator. I understand that the hunting is annoying but I do not think it is really "problem" in the sense that it is hurting something.
Perhaps UpRev has a solution for you? I would yap at them if you do not want to try putting the stock MAF housing back in the system.
Perhaps if we compare the stock MAF housing inside diameter to that of the STS intake pipe we could see if there was difference. However, I bet if that bung is slightly skewed, the readings would be off as well.
#1735
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When I had my car tuned, Mark bumped my idle and it seemed to help a little bit. Other than that, I just lived with it. Maybe because the diameter is only slightly different that at very low loads the difference is an issue but at partial throttle it goes away?
#1736
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I think a slight difference may be a enough to make a difference. I would ask uprev if they had a solution.
When I had my car tuned, Mark bumped my idle and it seemed to help a little bit. Other than that, I just lived with it. Maybe because the diameter is only slightly different that at very low loads the difference is an issue but at partial throttle it goes away?
When I had my car tuned, Mark bumped my idle and it seemed to help a little bit. Other than that, I just lived with it. Maybe because the diameter is only slightly different that at very low loads the difference is an issue but at partial throttle it goes away?
I would ask UpRev, but I don't feel like shelling out $500 for a flash. I'm debating spending $500 on a stage 0 fuel return just so I can have my fuel setup solid before heading to get a tune.
I also haven't messed with my TurboXS BCS yet. On the current WG spring it started to flutter with settings at 50% duty cycle. I have a stronger spring waiting to go in. But who knows, I'll probably have to drop some money on an EBC as well :-/ Hehe.
#1737
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Unless you are upgrading the turbo, you'll want to stick with 2.5" or smaller. Anything bigger will increase the spool time, at least according to people on here. I think I'm going with 2.25" TPs. Actually, goosegoose is pushing something like 600hp and he's only going with 2.5".
I however am/was running AAM 2.5 non resonated test pipes, and i made over 600rwhp. I am also running a larger turbo than the stock kit. My exhaust is HPC coated from the headers to the test pipes, and then heat wrapped all the way back to the turbo. Also, my exhaust tappers down slightly towards the turbo. I think you could run 3" test pipes with out effecting your spool time, as long as you tapered the exhaust at some point like mine is. However, one thing that might effect that is whether or not your turbo is a Ball bearing or not, mine is, because i wanted faster spool times.
#1738
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My car had idle issues, and that was even with a Haltech and a great tune done by performance factory. I talk to Bobby at CIN, and he decided to drill a small hole in the throttle body butterfly. He started with a very small hole and then we tested the idle, then moved up in bit sizes until it was good. Was an easy and cheap fix. After that I had no more idle fluctuations or stalls from the idle dropping out. Not something you should try though unless your confident in your skills, and will ing to by a new throttle body if you F*$k is up
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Sorry, but this caught my attention, goosegoose isn't pushing anything close to 600, atleast not from when i last heard from him. And i'm not talking trash or starting anything, i just know that he was having major issues with his build when my was being completed. He and I were building our cars at the same time, but he had major issues, and although he completed the build first, didn't post any numbers, and after talking to him, i know why. Last I heard he was going a completely different direction with his build, did that change?
I however am/was running AAM 2.5 non resonated test pipes, and i made over 600rwhp. I am also running a larger turbo than the stock kit. My exhaust is HPC coated from the headers to the test pipes, and then heat wrapped all the way back to the turbo. Also, my exhaust tappers down slightly towards the turbo. I think you could run 3" test pipes with out effecting your spool time, as long as you tapered the exhaust at some point like mine is. However, one thing that might effect that is whether or not your turbo is a Ball bearing or not, mine is, because i wanted faster spool times.
I however am/was running AAM 2.5 non resonated test pipes, and i made over 600rwhp. I am also running a larger turbo than the stock kit. My exhaust is HPC coated from the headers to the test pipes, and then heat wrapped all the way back to the turbo. Also, my exhaust tappers down slightly towards the turbo. I think you could run 3" test pipes with out effecting your spool time, as long as you tapered the exhaust at some point like mine is. However, one thing that might effect that is whether or not your turbo is a Ball bearing or not, mine is, because i wanted faster spool times.
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On the Idle issue, My idle is pretty stable between 770-850rpm, but I will see it drop to 750rpm every now and then and that is when my car will bog but that is only for 2-3 seconds. When my idle drop to to 750rpm, I noticed that one of my bank will go real lean (17:1-19:1) or some times both. I dont know if I have a leak or something coz I dont remember this happening before.