**OFFICIAL** STS C5 owners/installers thread
01-28-2006, 10:34 PM
#41
Melting Slicks
Thread Starter
Originally Posted by Tenderfoot
Does this mean they are smaller turbos such that they can spool up faster. Can someone explain what "The A/R is slightly tighter.." in the above quote means. I have drone at 2000-2200 RPMs, which gets a little quieter above that, so this might be the ticket for me. Did Rick say how high a boost level this housing will support on an LS1.
The exhaust and compressor housings on turbo chargers use a "scroll" design. For example, the exhaust housing's scroll is where the exhaust gasses enter the housing and are directed at the turbine. It's basically a smooth, tubular chamber that surrounds the turbine with a slot all the way around that acts as a nozzle to direct the exhaust gasses at the turbine. It's called a scroll because it slowly gets smaller in diameter as a goes around the turbine. This pressurizes the gasses, forcing them out of the slot/nozzle at a fast rate. In turbo-terms, the scroll is measured by the cross-sectional area of the scroll's "tube" (A) and the distance from the center of the "tube" to the turbine shaft (R). The values by themselves are not meaningful to the user and for the most part, R does not change much for different housings, but by dividing R into A, you get the A/R ratio. So, the A/R ratio of the exhaust housing refers to the size and shape of the scroll that is cast into the housing. It basically determines how restrictive the housing will be, versus how quickly the turbine will spin up. A lower A/R ratio (smaller scroll area, A) results in a more restrictive housing. This restriction speeds up the exhaust gasses and increases the amount that the gasses will expand. It's the speed and expansion of the gasses that causes the turbine to spin. So with a low A/R ratio, the turbine will spin up quicker, but as engine output and rpms increase, the restriction of the housing begins to build up too much back pressure on the engine, which reduces performance. A good rule of thumb for when there is too much back pressure is when the pressure in the exhaust manifold is more the half of the pressure in the cylinder. So basically, a larger A/R ratio will improve your engine's top end, while losing some mid range power and increasing turbo lag. A smaller A/R ratio will help the bottom and mid-range, but may effect the top end.
01-29-2006, 02:20 PM
#43
Pro
Member Since: Aug 2004
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Hey everyone,
I'm excited to say that I'm now an official STS TT owner, and installer in the near future. After quite alot of research and deliberation about what would be best for me from an FI package, I decided that the STS Twin Turbo system was what I wanted. I received the system Friday, and have been going over all that is included in the kit. I do admit that I am quite impressed with the quality and detail that went into designing and packaging the system.
With that said, I can only look forward to installing the system and seeing how well it performs on my car. I would like to thank everyone on the forum who has installed one of these kits and provide great feedback, which went along way in my decision to go with this kit. I look forward to much more support through this forum and the great members who offer their feedback and assistance.
I will have some time before I start the install, so I'm going to be watching how the development of some upgrades to the kit turn out. The top things I'll be watching are the following:
- Development of improved airbridge solution. Waiting to see what comes available besides the BBK unit.
- Addition of a second wastegate to the system. I would like to add a second wastegate along with a manual boost controller and set it to maybe 6.5-7 lbs of boost. I like this because I would be able to have a good max boost setting without the worry of any boost creep. I'm waiting to see if I can upgrade through STS for this, or if another alternative comes along.
- Upgrades to the standard oil return location in the oil filler cap. I like TaTommy888's solution, but I will have to see if it would work on an LS-1 engine like I have. Also, is there some kind of catchcan kit that I could get that would be a big enough upgrade to the stsndard STS unit, which would eliminate any concerns with the PCV system?
- Possibly the upgrade to the turbos that improves the spool responce. This is something I'm interested in, but we'll have to see if the improvement is that much better compared to what the cost will be.
Again, thank you to all who have been very supportive on this forum. I can't wait to see how some twin turbos feel.
Sincerely,
Chris
I'm excited to say that I'm now an official STS TT owner, and installer in the near future. After quite alot of research and deliberation about what would be best for me from an FI package, I decided that the STS Twin Turbo system was what I wanted. I received the system Friday, and have been going over all that is included in the kit. I do admit that I am quite impressed with the quality and detail that went into designing and packaging the system.
With that said, I can only look forward to installing the system and seeing how well it performs on my car. I would like to thank everyone on the forum who has installed one of these kits and provide great feedback, which went along way in my decision to go with this kit. I look forward to much more support through this forum and the great members who offer their feedback and assistance.
I will have some time before I start the install, so I'm going to be watching how the development of some upgrades to the kit turn out. The top things I'll be watching are the following:
- Development of improved airbridge solution. Waiting to see what comes available besides the BBK unit.
- Addition of a second wastegate to the system. I would like to add a second wastegate along with a manual boost controller and set it to maybe 6.5-7 lbs of boost. I like this because I would be able to have a good max boost setting without the worry of any boost creep. I'm waiting to see if I can upgrade through STS for this, or if another alternative comes along.
- Upgrades to the standard oil return location in the oil filler cap. I like TaTommy888's solution, but I will have to see if it would work on an LS-1 engine like I have. Also, is there some kind of catchcan kit that I could get that would be a big enough upgrade to the stsndard STS unit, which would eliminate any concerns with the PCV system?
- Possibly the upgrade to the turbos that improves the spool responce. This is something I'm interested in, but we'll have to see if the improvement is that much better compared to what the cost will be.
Again, thank you to all who have been very supportive on this forum. I can't wait to see how some twin turbos feel.
Sincerely,
Chris
01-29-2006, 02:51 PM
#44
Safety Car
Originally Posted by Hammer
Option information directly from STS"
"As far as sound levels go, the base TT kit is what I would call "Agressive". Not obnoxious enough to attract the attention of law officers by any means but she sounds like she's a runner. We have had some custom turbine housings cast up and now have them in stock. They are a direct replacement and install in about ½ hr. I would recommend these for all high-altitude Vette’s but they are a great addition to any system. The A/R is slightly tighter which gives you about 500 rpm quicker spool up which makes driving the car even more fun. There is no detectable high rpm power loss at base boost levels. Our prototype Z06 made 560rwhp at 6 psi w/ these housings. Obviously any car running high boost or running slightly larger displacement would run the standard turbine housings (The really big hp cars or big displacement engines will actually run a larger one). These housings completely get rid of the drone on the freeway between 2k and 3k rpm. The car sounds great and is very responsive in the lower-mid rpm range.
Talk to you all later, Rick @ STS"
"As far as sound levels go, the base TT kit is what I would call "Agressive". Not obnoxious enough to attract the attention of law officers by any means but she sounds like she's a runner. We have had some custom turbine housings cast up and now have them in stock. They are a direct replacement and install in about ½ hr. I would recommend these for all high-altitude Vette’s but they are a great addition to any system. The A/R is slightly tighter which gives you about 500 rpm quicker spool up which makes driving the car even more fun. There is no detectable high rpm power loss at base boost levels. Our prototype Z06 made 560rwhp at 6 psi w/ these housings. Obviously any car running high boost or running slightly larger displacement would run the standard turbine housings (The really big hp cars or big displacement engines will actually run a larger one). These housings completely get rid of the drone on the freeway between 2k and 3k rpm. The car sounds great and is very responsive in the lower-mid rpm range.
Talk to you all later, Rick @ STS"
So are you saying that the custom turbine housings are not applicable in high boost or larger displacement engines? And therefore no need for the upgrade because they already get rid of the drone?
Also how much is this upgrade.
Also if anyone knows, is STS the only TT kit that has the issue with the airbridge or is this common among high hp TT cars and boosted cars in general?
01-29-2006, 03:41 PM
#45
Drifting
Member Since: Nov 2002
Location: Sparta NJ
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Originally Posted by Jesse_Boyer
stole that from another sight as it sums it up nicely
.
Originally Posted by heavychevy
Also if anyone knows, is STS the only TT kit that has the issue with the airbridge or is this common among high hp TT cars and boosted cars in general?
ProtoVette -
on getting the kit. Some people have installed a 2nd wastegate to their kit, so this is certainly doable. I did not opt for this as minimum boost creep was reported by ECS on my install at 6 psi of boost. ECS installed a catch can on my install (I think its an AMW). They also tapped the pasenger side valve cover for the oil return for a cleaner install (I have an LS1). Honestly, on my A4 3600 stall TC coupe, I don't see any turbo lag. The base turbos in the kit spool up just fine. However, I do have resonance around 2K RPM. As such, I have interest in the possible solution mentioned by Doug (ECS) and Hammer in this thread.
01-29-2006, 03:48 PM
#46
Burning Brakes
Jesse-
Not sure if you have means to a truck/trailer or not, but I know that a fellow Corvette Club member just had an STS kit put on his car by the guy's that work in Karl Chevrolet's speed shop in Des Moines, IA. It's not too far from Omaha, I'm sure if you have any troubles that you could swing up up their way and it'd be done quick.
I think it took them an afternoon to put the kit on for the guy, sounds like he's enjoying it.
As far as I know, Carl Moyer's speed shop is a private deal for him, and his close buddies... I guess I'm not "in the loop" enough to know for sure. But I'm sure they'd be willing to lend a hand if needed!
Not sure if you have means to a truck/trailer or not, but I know that a fellow Corvette Club member just had an STS kit put on his car by the guy's that work in Karl Chevrolet's speed shop in Des Moines, IA. It's not too far from Omaha, I'm sure if you have any troubles that you could swing up up their way and it'd be done quick.
I think it took them an afternoon to put the kit on for the guy, sounds like he's enjoying it.
As far as I know, Carl Moyer's speed shop is a private deal for him, and his close buddies... I guess I'm not "in the loop" enough to know for sure. But I'm sure they'd be willing to lend a hand if needed!
12-30-2021, 09:16 AM
#51
Burning Brakes
I ordered a kit mid Nov. If it ever gets here I'll post up the pics you're looking for.
12-30-2021, 11:14 AM
#52
02-21-2022, 09:47 AM
#53
Melting Slicks
https://www.corvetteforum.com/forums...t-install.html
