STS update?
Former Vendor
Joined: Dec 2006
Posts: 2,239
Likes: 1
The STS kits look like a good deal, here is a list of my opinion of them, and why I don't sell them anymore:
1. STS claims that heat is not required to help spool the turbo, that exhaust velocity does the job.
Major retailers of the STS kits sell the kits with exhaust wrap, to help spool the turbo. We have done this at our shop, and it helps quite a bit. It is obvious that the closer to the engine the turbo is mounted, the more efficient it is going to be.
I copied this from the STS website.
"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?
No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.
Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".
Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."
So I take it the exhaust wrap should not make a difference?
2. You don't want to run catalytic converters with a rear mount turbo. Years ago a guy brought in a Ferrari to us that had a rear mount turbo. One of the catalytic converters internals came apart, as they sometimes do, and parts of it lodged into the turbo, ruining it. I predict that this will be happening to the STS turbo customers.
3. The oil return line is routed into the passenger side oil cap on the STS kits. This line has a habit of coming loose, and spraying oil into the engine compartment. It happened to us, and I have read where it has happened to other people.
These engines already have enough oil returning down through the heads, they don't need more! This is a bad design, and many people are rerouting the oil return line to the oil pan, where it should be in the first place. The problem with running the line to the pan is now you have to drill or punch a hole into the oil pan to run the oil line, unless you remove the oil pan. We recently removed the oil pan on a customer's car, and welded a bung into the pan for the oil return line.
4. The turbo hangs without brackets supporting it, and will sag over time. We add a bracket when we install these kits, I don't link seeing the turbo dangling there.
5. The air filter is in a bad location, as is susceptible to dust, water, dirt, etc. STS offers a cover that goes over the filter, but we found the cover seriously hinders performance. We proved that on our chassis dyno.
6. On the F Body STS kit, a driver side subframe connector cannot be used. STS claims their plumbing that is routed down the driver side does the job of a subframe connector. We find that humorous, at best!
7. The plumbing underneath the car hangs too low in my opinion, and you don't want a lowered car with an STS kit on it.
8. The silicone couplers that are provided with an STS front mount intercooler are thin, and we had two of them blow apart. The intercooler plumbing that was provided with the front mount intercooler option that we ordered for a customer's car was poorly routed, we ended up using our tubing from our front mount kits that we sell.
9. The oil lines sure have a long way to run, from the front to the rear, and back up front. If a leak developed, it could be a quick way to ruin an engine.
10. It would be relatively easy for someone to slide underneath the rear of an STS equipped car, and steal someones turbo.
11. The boost line running back up to the engine from the turbo has silicone couplers at various points along the way, and can blow apart.
12. Any exhaust leaks will diminish the efficiency of a rear mount turbo.
1. STS claims that heat is not required to help spool the turbo, that exhaust velocity does the job.
Major retailers of the STS kits sell the kits with exhaust wrap, to help spool the turbo. We have done this at our shop, and it helps quite a bit. It is obvious that the closer to the engine the turbo is mounted, the more efficient it is going to be.
I copied this from the STS website.
"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?
No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.
Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".
Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."
So I take it the exhaust wrap should not make a difference?
2. You don't want to run catalytic converters with a rear mount turbo. Years ago a guy brought in a Ferrari to us that had a rear mount turbo. One of the catalytic converters internals came apart, as they sometimes do, and parts of it lodged into the turbo, ruining it. I predict that this will be happening to the STS turbo customers.
3. The oil return line is routed into the passenger side oil cap on the STS kits. This line has a habit of coming loose, and spraying oil into the engine compartment. It happened to us, and I have read where it has happened to other people.
These engines already have enough oil returning down through the heads, they don't need more! This is a bad design, and many people are rerouting the oil return line to the oil pan, where it should be in the first place. The problem with running the line to the pan is now you have to drill or punch a hole into the oil pan to run the oil line, unless you remove the oil pan. We recently removed the oil pan on a customer's car, and welded a bung into the pan for the oil return line.
4. The turbo hangs without brackets supporting it, and will sag over time. We add a bracket when we install these kits, I don't link seeing the turbo dangling there.
5. The air filter is in a bad location, as is susceptible to dust, water, dirt, etc. STS offers a cover that goes over the filter, but we found the cover seriously hinders performance. We proved that on our chassis dyno.
6. On the F Body STS kit, a driver side subframe connector cannot be used. STS claims their plumbing that is routed down the driver side does the job of a subframe connector. We find that humorous, at best!
7. The plumbing underneath the car hangs too low in my opinion, and you don't want a lowered car with an STS kit on it.
8. The silicone couplers that are provided with an STS front mount intercooler are thin, and we had two of them blow apart. The intercooler plumbing that was provided with the front mount intercooler option that we ordered for a customer's car was poorly routed, we ended up using our tubing from our front mount kits that we sell.
9. The oil lines sure have a long way to run, from the front to the rear, and back up front. If a leak developed, it could be a quick way to ruin an engine.
10. It would be relatively easy for someone to slide underneath the rear of an STS equipped car, and steal someones turbo.
11. The boost line running back up to the engine from the turbo has silicone couplers at various points along the way, and can blow apart.
12. Any exhaust leaks will diminish the efficiency of a rear mount turbo.
Racer
Joined: Oct 2007
Posts: 311
Likes: 0
From: mammoth lakes ca
from what i have seen dealing with a friends 99 ss camero . the idea is a decent one . the bad thing is that they short cut in many areas like the post above . if one wanted to take the time to redo the plumbing they could be a good thing for a vet with the tight engine compartment that makes a standard turbo set up a bitch .
Le Mans Master
Joined: Jan 1999
Posts: 5,134
Likes: 23
From: Long Island NY
I'm not very technical about the STS solution, so forgive my lack of details.
I have an STS setup on my otherwise stock 2004 Z06. The only adjustment made was to plastic intake, which blew open at the seam when I went to 10 lbs of boost.
The car has run without a problem <knocking on wood>.
The coolant and oil temps stay normal even in the heat of summer.
Is it the BEST solution, probably not. But it was the right one for me at this time.
Jim
I have an STS setup on my otherwise stock 2004 Z06. The only adjustment made was to plastic intake, which blew open at the seam when I went to 10 lbs of boost.
The car has run without a problem <knocking on wood>.
The coolant and oil temps stay normal even in the heat of summer.
Is it the BEST solution, probably not. But it was the right one for me at this time.
Jim
Drifting
Joined: May 2002
Posts: 1,592
Likes: 6
From: Cresson TX
Just to clarify:
1) STS is the patent holder
2) Raptor LLC is developing the system independent from STS with sole rights to the C4 Corvette
3) System will be advertised by STS and Raptor
4) STS will provide basic parts (Turbo, oil return pump, etc...)
5) Raptor will supply all piping, brackets, IC and parts specific to our system
6) Raptor will be the only entity to sell the C4 system. STS will refer all sales to Raptor
7) Right now were are finishing up development and are providing progress reports only
Cheers,
Ron H
Drifting
Joined: May 2002
Posts: 1,592
Likes: 6
From: Cresson TX
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Drifting
Joined: May 2002
Posts: 1,592
Likes: 6
From: Cresson TX
Please see above for the clarification on who is producing and going to sell the C4 rear mount turbo system.
We are not STS...
I won't take sides on this one. Our single bushing turbo spools just fine and is comparable to the spool of a Pro Charger. Wrapping the exhaust may help but we are happy with our results.
Not so much. The newer style high flow metallic substrate CATS stay together just fine. The Raptor system comes standard with the replacements.
We do not like the design either but it is cheap, easy and efficient. We've not experienced the problems you've described on our test vehicle but that doesn't mean we don't believe you.
If you disconnect the coupling, you must carefully check the re-installation. The connector design is sound however if you don't let the collar return to its seat you could have the problem described.
Raptor thinks the design is jut too ugly and awkward for Corvettes. We have a new design that is both easy and hidden. Details will follow after testing is complete.
Oil returning to the head should not be a problem.
The C4 system has a bracket for the Turbo and also utilizes the stock exhaust hangers. No sag for the C4 System...
Yes the sock will rob some HP but you have to balance safety with HP. The C4 systems air filter is well protected. You have as much chance of swallowing water from a front cone filter as you do a well protected rear.
I'm not familiar with the F Body kit. We started from scratch.
The C4 system hangs no lower than the stock system. We take advantage of the large spare tire area under the car. Yes you do loose the spare tire.
We provide our own IC and parts which were independently designed.
This was a major concern when we began our design. We use aircraft style AN fittings and SS hoses. There is also a warning buzzer installed under the dash that will alert the driver of any low oil pressure situation. The system is way more robust than what is required and way more robust than you would find on your standard external engine oil cooler.
If you leave any car outside you have a chance of something getting stolen. To date STS claims that no one has complained of stolen turbo's. Yes it can happen,,, but...
Yes - But not a common event. All pipes have nipples which help secure the couplers. Proper length of hose, proper nipple size, proper clamping and occasional visual inspections will make this a very rare occurrence. This has not happened in any of our test Corvettes which have pushed up to 20psi.
Yes - even a header leak will reduce the efficiency of a conventional mount turbo. Unlike the STS system, the Raptor system is complete from manifold to exhaust and is made from SS not carbon. This should minimize the posibility...
We are not STS...
The STS kits look like a good deal, here is a list of my opinion of them, and why I don't sell them anymore:
1. STS claims that heat is not required to help spool the turbo, that exhaust velocity does the job.
Major retailers of the STS kits sell the kits with exhaust wrap, to help spool the turbo. We have done this at our shop, and it helps quite a bit. It is obvious that the closer to the engine the turbo is mounted, the more efficient it is going to be.
I copied this from the STS website.
"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?
No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.
Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".
Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."
So I take it the exhaust wrap should not make a difference?
1. STS claims that heat is not required to help spool the turbo, that exhaust velocity does the job.
Major retailers of the STS kits sell the kits with exhaust wrap, to help spool the turbo. We have done this at our shop, and it helps quite a bit. It is obvious that the closer to the engine the turbo is mounted, the more efficient it is going to be.
I copied this from the STS website.
"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?
No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.
Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".
Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."
So I take it the exhaust wrap should not make a difference?
2. You don't want to run catalytic converters with a rear mount turbo. Years ago a guy brought in a Ferrari to us that had a rear mount turbo. One of the catalytic converters internals came apart, as they sometimes do, and parts of it lodged into the turbo, ruining it. I predict that this will be happening to the STS turbo customers..
3. The oil return line is routed into the passenger side oil cap on the STS kits. This line has a habit of coming loose, and spraying oil into the engine compartment. It happened to us, and I have read where it has happened to other people. These engines already have enough oil returning down through the heads, they don't need more! This is a bad design, and many people are rerouting the oil return line to the oil pan, where it should be in the first place. The problem with running the line to the pan is now you have to drill or punch a hole into the oil pan to run the oil line, unless you remove the oil pan. We recently removed the oil pan on a customer's car, and welded a bung into the pan for the oil return line..
If you disconnect the coupling, you must carefully check the re-installation. The connector design is sound however if you don't let the collar return to its seat you could have the problem described.
Raptor thinks the design is jut too ugly and awkward for Corvettes. We have a new design that is both easy and hidden. Details will follow after testing is complete.
Oil returning to the head should not be a problem.
4. The turbo hangs without brackets supporting it, and will sag over time. We add a bracket when we install these kits, I don't link seeing the turbo dangling there..
5. The air filter is in a bad location, as is susceptible to dust, water, dirt, etc. STS offers a cover that goes over the filter, but we found the cover seriously hinders performance. We proved that on our chassis dyno..
6. On the F Body STS kit, a driver side subframe connector cannot be used. STS claims their plumbing that is routed down the driver side does the job of a subframe connector. We find that humorous, at best!.
7. The plumbing underneath the car hangs too low in my opinion, and you don't want a lowered car with an STS kit on it..
8. The silicone couplers that are provided with an STS front mount intercooler are thin, and we had two of them blow apart. The intercooler plumbing that was provided with the front mount intercooler option that we ordered for a customer's car was poorly routed, we ended up using our tubing from our front mount kits that we sell..
9. The oil lines sure have a long way to run, from the front to the rear, and back up front. If a leak developed, it could be a quick way to ruin an engine..
10. It would be relatively easy for someone to slide underneath the rear of an STS equipped car, and steal someones turbo..
11. The boost line running back up to the engine from the turbo has silicone couplers at various points along the way, and can blow apart..
12. Any exhaust leaks will diminish the efficiency of a rear mount turbo.
Last edited by rhanselman; Feb 10, 2008 at 01:52 PM.
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
I just installed a STS C5 TT kit
1. STS claims that heat is not required to help spool the turbo, that exhaust velocity does the job.
Major retailers of the STS kits sell the kits with exhaust wrap, to help spool the turbo. We have done this at our shop, and it helps quite a bit. It is obvious that the closer to the engine the turbo is mounted, the more efficient it is going to be.
I copied this from the STS website.
"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?
No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.
Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".
Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."
So I take it the exhaust wrap should not make a difference?
In my opinion heat wrap would make a slight difference just because the exhaust gases at the manifold is much hotter than they are if measured at the rear, there will be a considerable amount of heat loss, but not as much as you may think given engine RPM above 3500 RPM and under WOT. This kit I just installed started making boost at 3000 RPM and its rate increased very fast as engine speed increased until it peaked or until the wastegates opened at the boost controller setpoint.
2. You don't want to run catalytic converters with a rear mount turbo. Years ago a guy brought in a Ferrari to us that had a rear mount turbo. One of the catalytic converters internals came apart, as they sometimes do, and parts of it lodged into the turbo, ruining it. I predict that this will be happening to the STS turbo customers.
This is a potential issue, while it would be technically illegal to remove the CATs, in this situation where I would have a $3k worth of turbos after the CATs, I would definitely remove them.
3. The oil return line is routed into the passenger side oil cap on the STS kits. This line has a habit of coming loose, and spraying oil into the engine compartment. It happened to us, and I have read where it has happened to other people.
These engines already have enough oil returning down through the heads, they don't need more! This is a bad design, and many people are rerouting the oil return line to the oil pan, where it should be in the first place. The problem with running the line to the pan is now you have to drill or punch a hole into the oil pan to run the oil line, unless you remove the oil pan. We recently removed the oil pan on a customer's car, and welded a bung into the pan for the oil return line.
This is a non issue, the situation with the oil returning via the fill cap is gone. The return lines can be routed directly to the oil pan or via two separate lines to the valve covers. In this case, the lines were routed to both valve covers, and it works fine.
4. The turbo hangs without brackets supporting it, and will sag over time. We add a bracket when we install these kits, I don't link seeing the turbo dangling there.
I have never seen one break the hangers are high quality and will easily support the turbos in a C5/6, not to mention that the associated tubing also shares the load, even if the hanger breaks, the turbo wouldn’t come down because of the associated tubing is also suspending it.
5. The air filter is in a bad location, as is susceptible to dust, water, dirt, etc. STS offers a cover that goes over the filter, but we found the cover seriously hinders performance. We proved that on our chassis dyno.
In a C5 or C6 the air filters are behind the tail lamps. They are shielded quite well and are NOT subject to water as in a F body or a truck. Any filter if clogged with dirt regardless of where its located will hinder performance, the KN filters used in these kits are large and have 150% more filter area than is required per side.
6. On the F Body STS kit, a driver side subframe connector cannot be used. STS claims their plumbing that is routed down the driver side does the job of a subframe connector. We find that humorous, at best!
That is probably a true statement.
7. The plumbing underneath the car hangs too low in my opinion, and you don't want a lowered car with an STS kit on it.
This car was lowered and there is still ample room, but it is low, and I advised the customer to raise the car at least 1 inch. But this car was lowered at least 2 inches.
8. The silicone couplers that are provided with an STS front mount intercooler are thin, and we had two of them blow apart. The intercooler plumbing that was provided with the front mount intercooler option that we ordered for a customer's car was poorly routed, we ended up using our tubing from our front mount kits that we sell.
I can’t see how any of their couplings would blow apart, they are made of 4 ply silicone, not unless they boosted the **** out of it and I mean well over 15 PSI which is going to be high for most street applications anyway.
9. The oil lines sure have a long way to run, from the front to the rear, and back up front. If a leak developed, it could be a quick way to ruin an engine.
Yes, in reality that could happen, but unlikely if
A: the installer took enough time to route the hose properly so that there is no mechanical interference.
B: If the installer also upgraded the hose to Aeroquipe FC332 hose which is extra tough and is temperature rated to over 350 Deg F, and also heat shielded the hose where its exposed to radiant header heat and also added mechanical protection to the hose there would be no issues in this matter. I not only did the above but also upgraded all the fittings to AN type fittings.
10. It would be relatively easy for someone to slide underneath the rear of an STS equipped car, and steal someones turbo.
That is probably true, but most people with Corvettes or cars like this are going to keep the car in a locked garage. Christ people are stealing converters from under trucks across town, if someone wants it bad enough they are going to get it, this isn’t an issue of the kit being good or bad.
11. The boost line running back up to the engine from the turbo has silicone couplers at various points along the way, and can blow apart.
I call BS, if the installer does his job right they won’t come apart, especially if they are retorqued afterwards.
12. Any exhaust leaks will diminish the efficiency of a rear mount turbo.
A exhaust leak would diminish performance of a NA car if its near the o2 sensor, once again, if the installer does his job right and if the owner follows up on a retorque, it is a non issue. After all most people would or should retorque your new headers after a few heat cycles
In this particular car, it made 180+ hp over stock, the customer was ecstatic with the results, to me that is all that matters.
Major retailers of the STS kits sell the kits with exhaust wrap, to help spool the turbo. We have done this at our shop, and it helps quite a bit. It is obvious that the closer to the engine the turbo is mounted, the more efficient it is going to be.
I copied this from the STS website.
"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?
No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.
Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".
Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."
So I take it the exhaust wrap should not make a difference?
In my opinion heat wrap would make a slight difference just because the exhaust gases at the manifold is much hotter than they are if measured at the rear, there will be a considerable amount of heat loss, but not as much as you may think given engine RPM above 3500 RPM and under WOT. This kit I just installed started making boost at 3000 RPM and its rate increased very fast as engine speed increased until it peaked or until the wastegates opened at the boost controller setpoint.
2. You don't want to run catalytic converters with a rear mount turbo. Years ago a guy brought in a Ferrari to us that had a rear mount turbo. One of the catalytic converters internals came apart, as they sometimes do, and parts of it lodged into the turbo, ruining it. I predict that this will be happening to the STS turbo customers.
This is a potential issue, while it would be technically illegal to remove the CATs, in this situation where I would have a $3k worth of turbos after the CATs, I would definitely remove them.
3. The oil return line is routed into the passenger side oil cap on the STS kits. This line has a habit of coming loose, and spraying oil into the engine compartment. It happened to us, and I have read where it has happened to other people.
These engines already have enough oil returning down through the heads, they don't need more! This is a bad design, and many people are rerouting the oil return line to the oil pan, where it should be in the first place. The problem with running the line to the pan is now you have to drill or punch a hole into the oil pan to run the oil line, unless you remove the oil pan. We recently removed the oil pan on a customer's car, and welded a bung into the pan for the oil return line.
This is a non issue, the situation with the oil returning via the fill cap is gone. The return lines can be routed directly to the oil pan or via two separate lines to the valve covers. In this case, the lines were routed to both valve covers, and it works fine.
4. The turbo hangs without brackets supporting it, and will sag over time. We add a bracket when we install these kits, I don't link seeing the turbo dangling there.
I have never seen one break the hangers are high quality and will easily support the turbos in a C5/6, not to mention that the associated tubing also shares the load, even if the hanger breaks, the turbo wouldn’t come down because of the associated tubing is also suspending it.
5. The air filter is in a bad location, as is susceptible to dust, water, dirt, etc. STS offers a cover that goes over the filter, but we found the cover seriously hinders performance. We proved that on our chassis dyno.
In a C5 or C6 the air filters are behind the tail lamps. They are shielded quite well and are NOT subject to water as in a F body or a truck. Any filter if clogged with dirt regardless of where its located will hinder performance, the KN filters used in these kits are large and have 150% more filter area than is required per side.
6. On the F Body STS kit, a driver side subframe connector cannot be used. STS claims their plumbing that is routed down the driver side does the job of a subframe connector. We find that humorous, at best!
That is probably a true statement.
7. The plumbing underneath the car hangs too low in my opinion, and you don't want a lowered car with an STS kit on it.
This car was lowered and there is still ample room, but it is low, and I advised the customer to raise the car at least 1 inch. But this car was lowered at least 2 inches.
8. The silicone couplers that are provided with an STS front mount intercooler are thin, and we had two of them blow apart. The intercooler plumbing that was provided with the front mount intercooler option that we ordered for a customer's car was poorly routed, we ended up using our tubing from our front mount kits that we sell.
I can’t see how any of their couplings would blow apart, they are made of 4 ply silicone, not unless they boosted the **** out of it and I mean well over 15 PSI which is going to be high for most street applications anyway.
9. The oil lines sure have a long way to run, from the front to the rear, and back up front. If a leak developed, it could be a quick way to ruin an engine.
Yes, in reality that could happen, but unlikely if
A: the installer took enough time to route the hose properly so that there is no mechanical interference.
B: If the installer also upgraded the hose to Aeroquipe FC332 hose which is extra tough and is temperature rated to over 350 Deg F, and also heat shielded the hose where its exposed to radiant header heat and also added mechanical protection to the hose there would be no issues in this matter. I not only did the above but also upgraded all the fittings to AN type fittings.
10. It would be relatively easy for someone to slide underneath the rear of an STS equipped car, and steal someones turbo.
That is probably true, but most people with Corvettes or cars like this are going to keep the car in a locked garage. Christ people are stealing converters from under trucks across town, if someone wants it bad enough they are going to get it, this isn’t an issue of the kit being good or bad.
11. The boost line running back up to the engine from the turbo has silicone couplers at various points along the way, and can blow apart.
I call BS, if the installer does his job right they won’t come apart, especially if they are retorqued afterwards.
12. Any exhaust leaks will diminish the efficiency of a rear mount turbo.
A exhaust leak would diminish performance of a NA car if its near the o2 sensor, once again, if the installer does his job right and if the owner follows up on a retorque, it is a non issue. After all most people would or should retorque your new headers after a few heat cycles
In this particular car, it made 180+ hp over stock, the customer was ecstatic with the results, to me that is all that matters.
Thread Starter
Le Mans Master
Joined: Dec 2005
Posts: 6,994
Likes: 1,677
From: Southeast TX
[QUOTE=rhanselman;1564032618]We do care.
We will work the CARB# but as we said, first things first. We need to get the system out and see how much demand we have.
Cheers,
Ron[/QUOTE
Daaaammmm,
My patience is about out. I'm actively looking for an LT4 to mod the old fashioned way. Heads, cam, intake, exhaust. I'd rather be blown, but you boys keep pushing things back. My '95 coupe with auto tranny and 3.07 rear would be perfect for a rear mount. Have my eye on a sweet '96 LT4 coupe though. If I thought there would actually be a kit available in April, I'd wait. Been teased before. Good luck with your efforts. Deal on the LT4 might not happen. If it doesn't, and I don't find another one, I'll be on your list, but I'm not waiting. Need for speed needs to be satisfied!
We will work the CARB# but as we said, first things first. We need to get the system out and see how much demand we have.
Cheers,
Ron[/QUOTE
Daaaammmm,
My patience is about out. I'm actively looking for an LT4 to mod the old fashioned way. Heads, cam, intake, exhaust. I'd rather be blown, but you boys keep pushing things back. My '95 coupe with auto tranny and 3.07 rear would be perfect for a rear mount. Have my eye on a sweet '96 LT4 coupe though. If I thought there would actually be a kit available in April, I'd wait. Been teased before. Good luck with your efforts. Deal on the LT4 might not happen. If it doesn't, and I don't find another one, I'll be on your list, but I'm not waiting. Need for speed needs to be satisfied!
Drifting
Joined: May 2002
Posts: 1,592
Likes: 6
From: Cresson TX
Understand but development takes time. I don't believe we ever set a date to the public but we are close. If you go to our website you can sign up for the beta testing. If you are selected we will pay for your install at Henderson Performance there in SAN.
You could be blown away sooner than you think...
Cheers,
Ron
[QUOTE=old motorhead;1564068771]
You could be blown away sooner than you think...
Cheers,
Ron
[QUOTE=old motorhead;1564068771]
We do care.
We will work the CARB# but as we said, first things first. We need to get the system out and see how much demand we have.
Cheers,
Ron[/QUOTE
Daaaammmm,
My patience is about out. I'm actively looking for an LT4 to mod the old fashioned way. Heads, cam, intake, exhaust. I'd rather be blown, but you boys keep pushing things back. My '95 coupe with auto tranny and 3.07 rear would be perfect for a rear mount. Have my eye on a sweet '96 LT4 coupe though. If I thought there would actually be a kit available in April, I'd wait. Been teased before. Good luck with your efforts. Deal on the LT4 might not happen. If it doesn't, and I don't find another one, I'll be on your list, but I'm not waiting. Need for speed needs to be satisfied!
We will work the CARB# but as we said, first things first. We need to get the system out and see how much demand we have.
Cheers,
Ron[/QUOTE
Daaaammmm,
My patience is about out. I'm actively looking for an LT4 to mod the old fashioned way. Heads, cam, intake, exhaust. I'd rather be blown, but you boys keep pushing things back. My '95 coupe with auto tranny and 3.07 rear would be perfect for a rear mount. Have my eye on a sweet '96 LT4 coupe though. If I thought there would actually be a kit available in April, I'd wait. Been teased before. Good luck with your efforts. Deal on the LT4 might not happen. If it doesn't, and I don't find another one, I'll be on your list, but I'm not waiting. Need for speed needs to be satisfied!
