Official STS Rear Mount Turbo Discussion Thread
Well, it took me an hour or so, but I figured out how the STS electrical stuff works. I would be able to scrap the solenoid for the PCV system (still need the 1 psi switch hooked up to the intake to trigger the oil pump into high gear) and not affect anything electrical related.
Clearly, STS is using a hobbs 1 psi pressure switch. Why not swap a pressure swirch with a low vaccum switch. This way the selonoids will close before you ever hit boost. They are available and that is what I will be using on my project build. These switches stay open under vacuum and close as soon as they see anything other then vacuum. If the switch can't handle enough current for your oil pump then just get a 12 relay as they are good for 30A, and cost about $5.
On a side note, can't you guys use simple automotive checkvalves to eliminate crankcase boost? I used them on my old project and they work really well. I'm new to the Z so maybe there is a limitation of some sort, but then again it's just vacuum lines just like any car.
On a side note, can't you guys use simple automotive checkvalves to eliminate crankcase boost? I used them on my old project and they work really well. I'm new to the Z so maybe there is a limitation of some sort, but then again it's just vacuum lines just like any car.
I know I created another thread for questions, but I might as well just ask them in here. Sometime us STS guys will have to make a FAQ thread like the Vortech one.
How many of you guys have high-flow cats? Looking at the install directions, I noticed that they are using test pipes. My Berk HFC's have the catalyst part of the cat up close towards the exhaust manifold. If the charge pipe fits around it, it's going to be VERY tight. That charge pipe is going to be freakin' hot. Should I adhere some of that reflective heat wrap on the side of a charge pipe that's facing the cat? I don't think I'll be able to wrap the HFC due to its shape, and I won't get getting them jet-hotted until next spring.
How many of you guys have high-flow cats? Looking at the install directions, I noticed that they are using test pipes. My Berk HFC's have the catalyst part of the cat up close towards the exhaust manifold. If the charge pipe fits around it, it's going to be VERY tight. That charge pipe is going to be freakin' hot. Should I adhere some of that reflective heat wrap on the side of a charge pipe that's facing the cat? I don't think I'll be able to wrap the HFC due to its shape, and I won't get getting them jet-hotted until next spring.
I am running some cheap ebay test pipes(which are just fine and have never cracked) . My charge air pipe hit them at certain loads. So I took a hammer to it and made it go away. I ended having to bang out several places so the charge air pipe would clear my aftermarket sways.
This is with the side pipe. I am assuming you are running the center pipe?
I would highly suggest wrapping with some header wrap as much of your manifolds and down pipes/cats as possible. I made a thread one time asking for temperatures, anyway the highest are right around the cats.
The key with any turbocharger, steam turbine, gas turbine, water turbine or whatever is increasing the avalible energy for the turbine to do work. W=h1-h2. In a turbocharger system that is mounted close to the exhaust ports, the gases have little time to give up much heat before they get to the turbine.
W is work
h1 is enthalpy of the fluid into the turbine
h2 is enthalpy of the fluid exiting the turbine
So if h1 is increased and h2 is lowered, more energy is aviable to the turbine to do work. We can't do much about h1 so If we raise h1 then we will get more work out of our turbine for a given flow of exhaust gases. As STS owners we can insulate our headers, test pipes, and mid pipes. Many people have done this with jethot and header wrap. I think the next step is to insulate the whole exhaust system with a ceramic fiber blanket. When I have time, I am going to do it.
I am running the big nismo mid pipe. Running a larger diameter reduces exhaust gas velocities which reduces loses to friction in the piping. By reducing frictional loses before the turbine I increased h1. However, something I was not thinking about at all...the larger piping has more surface area. Larger surface area to lose heat to the atmosphere. So the gains I made by running a larger mid pipe and Y pipe were lost to the increased surface area of the mid pipe. This resulted in a decreased h1 as compared to people who are running the stock midpipe.
The major advantage to the STS kit is in the fact that underhood temperatures are down which puts less stress on engine internals. The kit will never be as efficient as a front mounted turbo kit but there are some things we can do to help.
W is work
h1 is enthalpy of the fluid into the turbine
h2 is enthalpy of the fluid exiting the turbine
So if h1 is increased and h2 is lowered, more energy is aviable to the turbine to do work. We can't do much about h1 so If we raise h1 then we will get more work out of our turbine for a given flow of exhaust gases. As STS owners we can insulate our headers, test pipes, and mid pipes. Many people have done this with jethot and header wrap. I think the next step is to insulate the whole exhaust system with a ceramic fiber blanket. When I have time, I am going to do it.
I am running the big nismo mid pipe. Running a larger diameter reduces exhaust gas velocities which reduces loses to friction in the piping. By reducing frictional loses before the turbine I increased h1. However, something I was not thinking about at all...the larger piping has more surface area. Larger surface area to lose heat to the atmosphere. So the gains I made by running a larger mid pipe and Y pipe were lost to the increased surface area of the mid pipe. This resulted in a decreased h1 as compared to people who are running the stock midpipe.
The major advantage to the STS kit is in the fact that underhood temperatures are down which puts less stress on engine internals. The kit will never be as efficient as a front mounted turbo kit but there are some things we can do to help.
Last edited by Ahsmo; Oct 5, 2008 at 09:00 AM.
Clearly, STS is using a hobbs 1 psi pressure switch. Why not swap a pressure swirch with a low vaccum switch. This way the selonoids will close before you ever hit boost. They are available and that is what I will be using on my project build. These switches stay open under vacuum and close as soon as they see anything other then vacuum. If the switch can't handle enough current for your oil pump then just get a 12 relay as they are good for 30A, and cost about $5.
On a side note, can't you guys use simple automotive checkvalves to eliminate crankcase boost? I used them on my old project and they work really well. I'm new to the Z so maybe there is a limitation of some sort, but then again it's just vacuum lines just like any car.
On a side note, can't you guys use simple automotive checkvalves to eliminate crankcase boost? I used them on my old project and they work really well. I'm new to the Z so maybe there is a limitation of some sort, but then again it's just vacuum lines just like any car.
As for the checkvalve - the STS solenoid actually has a vent port on it with a small filter. So when the pressure switch engages, it powers the solenoid which will prevent the boost from entering the crankcase, but will also allow the crankcase to vent. However, the driver's side breather port should vent enough on it's own, so a simple check valve should actually work just fine. Now...I have to find one of those.
Good idea on the switch. I'm trying to search online, but haven't found anything. The STS harness utilizes a relay already. When the pressure switch engages, it simply switches the relay to send power through a non-resisted wire to cause the oil pump to get more power.
As for the checkvalve - the STS solenoid actually has a vent port on it with a small filter. So when the pressure switch engages, it powers the solenoid which will prevent the boost from entering the crankcase, but will also allow the crankcase to vent. However, the driver's side breather port should vent enough on it's own, so a simple check valve should actually work just fine. Now...I have to find one of those.
As for the checkvalve - the STS solenoid actually has a vent port on it with a small filter. So when the pressure switch engages, it powers the solenoid which will prevent the boost from entering the crankcase, but will also allow the crankcase to vent. However, the driver's side breather port should vent enough on it's own, so a simple check valve should actually work just fine. Now...I have to find one of those.
Just google GM adjustable vacuum switch, or something like that. They use these on GM's as torque converter lock switches. I will use automotive check valves as any stock turbo car has them, they are mechanical and much less prone to failure than any selonoid. Not to mention that no wiring is needed.
Last edited by BoostedProbe; Oct 5, 2008 at 09:37 AM.
Just google GM adjustable vacuum switch, or something like that. They use these on GM's as torque converter lock switches. I will use automotive check valves as any stock turbo car has them, they are mechanical and much less prone to failure than any selonoid. Not to mention that no wiring is needed.
However, I did order a few of these, and will at least use one between the intake manifold and catch-can/PCV valve...
http://www.usplastic.com/catalog/var...riant_id=64175
Are you guys running a breather filter off the driver's side valve cover like the instructions say? If so, are you having any high-idle issues, much like a vacuum leak? I'm not sure if the PCV valve is closed under high vacuum (idle). If not, then I would think there would no doubt be a "vacuum leak" issue with this setup.
Alright guys, I decided to completely scrap the vacuum hose connecting from the intake/charge tube to one of the PCV crossover ports, along with the solenoid. It seems completely pointless. Obviously I'm still going to keep the hobbs switch hooked up to the intake tube.
Over winter, I may consider rigging up an electric vacuum pump that is kicked on when I'm in boost. You can get a GM LTI pump for about $100 new, or < $50 from a junk yard. Then you just need to hook it up to a relay, which gets its signal from the hobbs 1 psi switch. I'm just not sure if it will be able to handle being frequently kicked on and off going into and out of boost. It's also kind of big, so I don't know where it could be mounted.
Over winter, I may consider rigging up an electric vacuum pump that is kicked on when I'm in boost. You can get a GM LTI pump for about $100 new, or < $50 from a junk yard. Then you just need to hook it up to a relay, which gets its signal from the hobbs 1 psi switch. I'm just not sure if it will be able to handle being frequently kicked on and off going into and out of boost. It's also kind of big, so I don't know where it could be mounted.
Yeah, I've been talking about why for a past few posts (I think). It's just that with the crankcase breather filter, STS's hose from the intake through their solenoid to the PCV crossover tube seems useless. Air can already come in through the breather filter at idle, and blow-by can exit under boost.
Well, I got the rest of my stuff today from STS. I believe it's now been 5 weeks since I first placed my order and was told it would ship out in 2-3 weeks :-/
I'm glad that they now ship the kit with exhaust tips
Wow, they go to great lengths to re-brand almost everything, including the Tial BOV and WG
I gotta say the piping is very heavy, and looks like crap. I need to bust out the polish and hopefully bring some shine out. There's also some surface rust on the inside of some of the pipes, especially where it has been welded
CIN Motorsports' website says the piping is HPC coated inside and out, but they don't coat the inside. Plus, in my MAF pipe there some nice crystallized coating in there that almost looks as though you can rub it off - it's very rough in there (hard to tell from the picture)
I mounted up the oil pump and fed the return line into my Vortech fitting tapped into the upper oil pan. Should work out nice. I'll get a pic of it later.
I should have everything done and attempt to get things running on Wednesday *fingers crossed*.
Oh, also since I got goosegoose's used turbo, I blasted the turbine housing, painted it with VHT, and baked it in the oven to cure it.
I'm glad that they now ship the kit with exhaust tips
Wow, they go to great lengths to re-brand almost everything, including the Tial BOV and WG
I gotta say the piping is very heavy, and looks like crap. I need to bust out the polish and hopefully bring some shine out. There's also some surface rust on the inside of some of the pipes, especially where it has been welded
CIN Motorsports' website says the piping is HPC coated inside and out, but they don't coat the inside. Plus, in my MAF pipe there some nice crystallized coating in there that almost looks as though you can rub it off - it's very rough in there (hard to tell from the picture)
I mounted up the oil pump and fed the return line into my Vortech fitting tapped into the upper oil pan. Should work out nice. I'll get a pic of it later.
I should have everything done and attempt to get things running on Wednesday *fingers crossed*.
Oh, also since I got goosegoose's used turbo, I blasted the turbine housing, painted it with VHT, and baked it in the oven to cure it.
Arn't those pipes suposed to be stainless? Stainless does not rust, and if the welds are rusty they used the wrong filler rod when they tig welded. Probably a 309 rod.
I looked at this kit a while ago and decided to do my own instead. It won't be a rear mount turbo, I'll mount it just under the gear shifter. I'll save about $3k this way and it will all be stainless.
Good luck on your install.
Oh, forgot to mention. My high speed savenge pump will be triggered through the oil pressure. That to me seems the most logical way. The switch will be adjustable and probably set to switch the oil pump in to high gear when oil pressure hits 40-45psi.
I looked at this kit a while ago and decided to do my own instead. It won't be a rear mount turbo, I'll mount it just under the gear shifter. I'll save about $3k this way and it will all be stainless.
Good luck on your install.
Oh, forgot to mention. My high speed savenge pump will be triggered through the oil pressure. That to me seems the most logical way. The switch will be adjustable and probably set to switch the oil pump in to high gear when oil pressure hits 40-45psi.
Last edited by BoostedProbe; Oct 7, 2008 at 06:30 AM.
When Jet-Hot coated my exhaust pipes "inside and out" it looked the same way - perfect on the outside and somewhat crude on the inside. Perhaps this is just an industry standard with coatings. However, that surface rust doesn't seem right. My pipes were not like that when I received them. Hopefully it's easily polished out. Lastly, I didn't know STS re-branded everything. I know my kit was the first G35 kit made, but the only item with the STS logo was the oil pump.
Keep us updated on how things go.
Good luck!
Keep us updated on how things go.
Good luck!
Thats par for the course with them. Tell you one thing and get another.
I have a fuel pump for a tacoma that I have been waiting to send back to STS. It has been nearly a year since I was sent the wrong pump. I send them an email to harass them every month or so.
I have a fuel pump for a tacoma that I have been waiting to send back to STS. It has been nearly a year since I was sent the wrong pump. I send them an email to harass them every month or so.
Customer service at its finest.
