Official STS Rear Mount Turbo Discussion Thread
I had popping at idle on a different boosted car, it was do to running rich.
On a side note, instead of all this PCV crap, wouldn't it be a good idea to run a hose from the turbo suction side to a catch can. This way you can route all your crankcase hoses to one place that is always in vacuum. Again, I did this on a different boosted car but it worked flawlesly.
I'm new to the 350 world and that may not work with this system, just a thought.
On a side note, instead of all this PCV crap, wouldn't it be a good idea to run a hose from the turbo suction side to a catch can. This way you can route all your crankcase hoses to one place that is always in vacuum. Again, I did this on a different boosted car but it worked flawlesly.
I'm new to the 350 world and that may not work with this system, just a thought.
I had popping at idle on a different boosted car, it was do to running rich.
On a side note, instead of all this PCV crap, wouldn't it be a good idea to run a hose from the turbo suction side to a catch can. This way you can route all your crankcase hoses to one place that is always in vacuum. Again, I did this on a different boosted car but it worked flawlesly.
I'm new to the 350 world and that may not work with this system, just a thought.
On a side note, instead of all this PCV crap, wouldn't it be a good idea to run a hose from the turbo suction side to a catch can. This way you can route all your crankcase hoses to one place that is always in vacuum. Again, I did this on a different boosted car but it worked flawlesly.
I'm new to the 350 world and that may not work with this system, just a thought.
You don't want to scrap the passenger PCV hose to the plenum, because it creates way more vacuum while cruising than a turbo inlet tube hookup would.
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From: NOVA
Damn it, now why do you have to take me from a high after just driving the car for the first time, to me being worried now 
Well, I'm pumped. I got the car done just in time for a Z car cruise tomorrow
It took me forever, but it's running. At first the dump pipe off of the turbine housing wasn't on quite straight. And the Napa exhaust gasket leaked like crazy. I went to get a different one, and that leaked. So I RTV'ed the crap out of it, but I think it still leaks. The STS flange is good, it's just that the stock mid-pipe flange bends on the edges so there isn't a good seal towards the middle. I'll have to figure out what I'm going to do about that. Might have to have an exhaust shop weld up a nice solid flat flange.
Actually, when I first started it up I was like "holy hell there's a huge exhaust leak" - but it's just the way it sounds, haha. It's louder than I thought it would be, but sounds amazing. However, driving around I think there are multiple exhaust leaks, along with a nice little rattle at times from one of the charge pipes maybe?
I don't have a drip of fluid anywhere, which surprised me. I'll top off my oil in the morning. After letting it idle for a bit to fill up the lines, I was about 1/2 quart low. I have an oil pan spacer for added security, so I'll be running 7 qrts now.
I took it out in the dark and was really worried that something would go wrong - I even brought a backup battery for my flashlight. I took it slow not going into boost to make sure everything was good. Ran it to 2 psi, changed the AFR a bit. Ran it again, did the same. Then I found an industrial area and did like 8 runs with it - about 4 of them all out. 3.5 psi on the wastegate!!
(reference line from compressor, no BCS action) It's actually really nice since I can flush out the AFR tuning down low while being able to go WOT. With the Vortech, I set the fuel cutoff low when tuning it for the first time when I wanted to start tuning the lower loads.
Here's an awesome graph from LogAnalyzer (this thing really needs to have more flexibility)...
So, it seems as though *so far* the only problems I'm having are with idle. I took a video, but it didn't capture the sounds good enough. It idles quite rough, as though it's starved for air. The exhaust seems to backfire as well after you let it sit for a bit - it just goes "pop....pop..........pop". It also backfires pretty good on decel, so I don't know if this is usual or not.
Anyone else have problems with their idle? I installed a check valve in my PCV hose to keep boost out of my ghetto catch can and PCV valve - and it doesn't seem to flow much air. Doubt that would be the issue though.
Well, I'm pumped. I got the car done just in time for a Z car cruise tomorrow
It took me forever, but it's running. At first the dump pipe off of the turbine housing wasn't on quite straight. And the Napa exhaust gasket leaked like crazy. I went to get a different one, and that leaked. So I RTV'ed the crap out of it, but I think it still leaks. The STS flange is good, it's just that the stock mid-pipe flange bends on the edges so there isn't a good seal towards the middle. I'll have to figure out what I'm going to do about that. Might have to have an exhaust shop weld up a nice solid flat flange.Actually, when I first started it up I was like "holy hell there's a huge exhaust leak" - but it's just the way it sounds, haha. It's louder than I thought it would be, but sounds amazing. However, driving around I think there are multiple exhaust leaks, along with a nice little rattle at times from one of the charge pipes maybe?
I don't have a drip of fluid anywhere, which surprised me. I'll top off my oil in the morning. After letting it idle for a bit to fill up the lines, I was about 1/2 quart low. I have an oil pan spacer for added security, so I'll be running 7 qrts now.
I took it out in the dark and was really worried that something would go wrong - I even brought a backup battery for my flashlight. I took it slow not going into boost to make sure everything was good. Ran it to 2 psi, changed the AFR a bit. Ran it again, did the same. Then I found an industrial area and did like 8 runs with it - about 4 of them all out. 3.5 psi on the wastegate!!
(reference line from compressor, no BCS action) It's actually really nice since I can flush out the AFR tuning down low while being able to go WOT. With the Vortech, I set the fuel cutoff low when tuning it for the first time when I wanted to start tuning the lower loads.Here's an awesome graph from LogAnalyzer (this thing really needs to have more flexibility)...
So, it seems as though *so far* the only problems I'm having are with idle. I took a video, but it didn't capture the sounds good enough. It idles quite rough, as though it's starved for air. The exhaust seems to backfire as well after you let it sit for a bit - it just goes "pop....pop..........pop". It also backfires pretty good on decel, so I don't know if this is usual or not.
Anyone else have problems with their idle? I installed a check valve in my PCV hose to keep boost out of my ghetto catch can and PCV valve - and it doesn't seem to flow much air. Doubt that would be the issue though.
The backfire issue is normal (at least for me). When I am decelerating towards the lower RPM's I tend to get this.
I picked up some furniture padding (soft felt on one side and adhesive on the other) and applied to all areas that the charge pipe came in contact w/ other metal. No more noises.
Here are pics (I have a different Y-pipe now).
I need to wrap mine also... Not sure if it is my brand of testpipe but mine is loud and does smell
No wonder I'm the 3rd owner of this TestPipe (Not sure what brand I have but I think it's UTR)... lol I think Teg and Daniel both have/had the Invidia and both are happy with them.
Washwiz,
Did you noticed any difference after heatwraping the exhaust?
No wonder I'm the 3rd owner of this TestPipe (Not sure what brand I have but I think it's UTR)... lol I think Teg and Daniel both have/had the Invidia and both are happy with them. Washwiz,
Did you noticed any difference after heatwraping the exhaust?
Have any of you guys switched out the spring in the TiAL BOV? I'm getting some flutter at low load, and think maybe some compressor surge? I don't really know how to check for it, although my friend said it sounded like it.
Also, should the BOV be open a little bit at idle? Mine isn't - not sure if it should be or not.
Also, should the BOV be open a little bit at idle? Mine isn't - not sure if it should be or not.
Man...I have a pretty big exhaust leak somewhere. It's noticeable when rolling on it from low RPMs as the system gets pressurized. However, rolling underneath it tonight I don't see any signs anywhere of an exhaust leak (no carbon buildup). My rusty *** 40,000 mile y-pipe might just be leaking in a bunch of different places.
Any suggestions on a cheap alternative to the stock y-pipe? A friend gave me his almost new '08 exhaust, but the y-pipe doesn't fit with the STS piping.
Any suggestions on a cheap alternative to the stock y-pipe? A friend gave me his almost new '08 exhaust, but the y-pipe doesn't fit with the STS piping.
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I would stick with a stock y pipe or at least stock diameter (I don't know of anyone that makes a stock diameter aftermarket pipe). But that being said I did have to replace mine because I was getting a leak from the flex joints. I would also check your test pipes/cats. I also had a crack in one of the 02 sensor bungs on one of my test pipes, so you might want to check that.
when my y pipe failed it wasn't really audible, but when the test pipe cracked it was louder and sounded like ****
when my y pipe failed it wasn't really audible, but when the test pipe cracked it was louder and sounded like ****
Have any of you guys switched out the spring in the TiAL BOV? I'm getting some flutter at low load, and think maybe some compressor surge? I don't really know how to check for it, although my friend said it sounded like it.
Also, should the BOV be open a little bit at idle? Mine isn't - not sure if it should be or not.
Also, should the BOV be open a little bit at idle? Mine isn't - not sure if it should be or not.
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From: NOVA
As far as spool time, not much. Going w/ test pipes and Y-pipe negated that anyway. It dose seem to pull harder. I have not had a new tune since I put on the test pipes. I also just purchased an HKS EBC (not installed yet).
There's always the new Motordyne XYZ Pipe.
Isn't this a bit of compressor surge?
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I'm actually going to order some of the softer BOV springs when I order a .5 bar wastegate spring from Tial. I know SnyperZ (I think that's his SN) bumped his on the PL kit down two springs until he got it right.
Side note: when rolling at low rpm and you punch it, does the exhaust kind of sound like an exhaust leak until it spools up? I swore I had an exhaust leak, but driving today it almost sounds like it's just the air exiting the turbo at low rpm WOT. Maybe it sill is, but I have yet to pinpoint it. It's just quite embarrassing because the car sounds like it has a rusted out exhaust sometimes.
Hopefully I won't have too many more questions
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I'm actually going to order some of the softer BOV springs when I order a .5 bar wastegate spring from Tial. I know SnyperZ (I think that's his SN) bumped his on the PL kit down two springs until he got it right.
Side note: when rolling at low rpm and you punch it, does the exhaust kind of sound like an exhaust leak until it spools up? I swore I had an exhaust leak, but driving today it almost sounds like it's just the air exiting the turbo at low rpm WOT. Maybe it sill is, but I have yet to pinpoint it. It's just quite embarrassing because the car sounds like it has a rusted out exhaust sometimes.
Hopefully I won't have too many more questions
yeah, that sound is normal. Also when you rev the engine just before you launch that sound is normal. It is the Turbo spinning lightly that created that sound. Rear-Mount sound different from your regular Front-Mount Turbo. Compressor surge only happen when the TB is close and the BOV dont open. You dont normally hear compressor surge when WOT. Also are you sure you dont already have the .5 bar WG spring? Maybe you can open the WG and see what color is the spring.. I think green is .5 bar...
Last edited by athenG; Oct 14, 2008 at 06:01 AM.
Your BOV is opening at 1-3psi when the TB close right? If your BOV is not opening then going to a lighter spring might help. You still want to have some pressure left even after the BOV and I doubt you'll get that much of a compressor surge coz the turbo is all the way in the back.. You really have to be boosting high for the pressure to build up.. just my .02