STS vs Intercooled turbo and pressure drops.
05-14-2004, 06:23 PM
#21
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Great info, folks! I agree with most all of it. As the saying goes, an internal combustion engine broken down to laymans terms means "air pump". More air in = more power. This is why the term "air density" explains more than "air pressure". Another way to look at it is your tires. Becha most people have to add air during the winter and bleed air during the summer. This is a good way to validate temperature vs density, at least to my sometimes groggy mind.
I have seen a STS kit mated to a Dodge hemi recently. They were boosting 5-6psi with no alcohol, 12-13psi of boost with methanol. This was in a big quad cab. No hint of detonation or glowing exhaust pieces. Made it move down the track in the high 12's on meth ( adjusted for altitude, not sure of the conversion factor with FI ).
My two cents, the location of the STS near the axle is scary to me, especially if there is water around. Not sure how the turbo would like ingesting some H20 but the reps say they have not run into any issues.
I have seen a STS kit mated to a Dodge hemi recently. They were boosting 5-6psi with no alcohol, 12-13psi of boost with methanol. This was in a big quad cab. No hint of detonation or glowing exhaust pieces. Made it move down the track in the high 12's on meth ( adjusted for altitude, not sure of the conversion factor with FI ).
My two cents, the location of the STS near the axle is scary to me, especially if there is water around. Not sure how the turbo would like ingesting some H20 but the reps say they have not run into any issues.
05-15-2004, 03:27 AM
#22
TECH Apprentice
you know i just had a thought, I bet if you ran through water for a sec it might actually help, thing about it, the turbo is still several hundred degrees not to mention a super fast spining turbine, if you did get water in there I bet between the turbo heat and getting choped to pieces by the turbine its self your gonna have nothing but vaper and probly cooler the IATs . hmmmm im much less worred about it now ( plus it has 20 feet of pipe to combine with the rest of the intake charge )
Originally Posted by ktmrider
Great info, folks! I agree with most all of it. As the saying goes, an internal combustion engine broken down to laymans terms means "air pump". More air in = more power. This is why the term "air density" explains more than "air pressure". Another way to look at it is your tires. Becha most people have to add air during the winter and bleed air during the summer. This is a good way to validate temperature vs density, at least to my sometimes groggy mind.
I have seen a STS kit mated to a Dodge hemi recently. They were boosting 5-6psi with no alcohol, 12-13psi of boost with methanol. This was in a big quad cab. No hint of detonation or glowing exhaust pieces. Made it move down the track in the high 12's on meth ( adjusted for altitude, not sure of the conversion factor with FI ).
My two cents, the location of the STS near the axle is scary to me, especially if there is water around. Not sure how the turbo would like ingesting some H20 but the reps say they have not run into any issues.
I have seen a STS kit mated to a Dodge hemi recently. They were boosting 5-6psi with no alcohol, 12-13psi of boost with methanol. This was in a big quad cab. No hint of detonation or glowing exhaust pieces. Made it move down the track in the high 12's on meth ( adjusted for altitude, not sure of the conversion factor with FI ).
My two cents, the location of the STS near the axle is scary to me, especially if there is water around. Not sure how the turbo would like ingesting some H20 but the reps say they have not run into any issues.
05-15-2004, 08:05 AM
#23
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I'm not so sure I would rely on water puddles to provide a cooling effect 
, however, I think that a K&N Filtercharger placed over the air filter would do wonders. If people can use open element air filters on fourwheelers, go-karts, and snowmobiles etc. then I bet it would work fine for trucks. I beleive they do offer the wraps for the large automotive filter sizes. Anyways, just a thought.
, however, I think that a K&N Filtercharger placed over the air filter would do wonders. If people can use open element air filters on fourwheelers, go-karts, and snowmobiles etc. then I bet it would work fine for trucks. I beleive they do offer the wraps for the large automotive filter sizes. Anyways, just a thought.
05-15-2004, 09:13 AM
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LOL
Seems like alot of talking in circles if you ask me.
I drop off my truck tomorrow to install the kit. We'll see how it goes. If it sucks I'll let ya know with dyno and track #s. I wont try to discredit a system without actual knowledge of the system itself and bunch of theoretical #s. I'll do it with actual results or lackthereof.
Seems like alot of talking in circles if you ask me.
I drop off my truck tomorrow to install the kit. We'll see how it goes. If it sucks I'll let ya know with dyno and track #s. I wont try to discredit a system without actual knowledge of the system itself and bunch of theoretical #s. I'll do it with actual results or lackthereof.
05-15-2004, 09:38 AM
#25
Originally Posted by F8LPONY
LOL
Seems like alot of talking in circles if you ask me.
I drop off my truck tomorrow to install the kit. We'll see how it goes. If it sucks I'll let ya know with dyno and track #s. I wont try to discredit a system without actual knowledge of the system itself and bunch of theoretical #s. I'll do it with actual results or lackthereof.
Seems like alot of talking in circles if you ask me.
I drop off my truck tomorrow to install the kit. We'll see how it goes. If it sucks I'll let ya know with dyno and track #s. I wont try to discredit a system without actual knowledge of the system itself and bunch of theoretical #s. I'll do it with actual results or lackthereof.
05-15-2004, 09:59 AM
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Originally Posted by parish8
sweet!!, now hurry up!!
I had to wait till the kit came in and the shop had time. I don't have time to do it myself and I need their tuning skills so wait I did. I just hope I went big enough on the turbo. I am not sure what a GT35 comes out to but I am sure it is smaller than a T76. Then again it might be ok on my smaller motor.
05-15-2004, 06:15 PM
#28
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WHOA! I forgot to get email notifications to this thread. it got some good responces.
Guys; what a lot of you are missing is that the long pipe
a. hurts in spooling up turbo
b. hurts in getting air to the motor.
a: The exhuast gasses have further to travel so more friction with the walls and hence slow down. they also cool down and get slower so they will spool slower.
b. the piping will be very inefficent at cooling the air. The idea is to cool as much as possible while decreasing pressure as little as possible ( or have as little resistance as possible)
Heat loss wont really effect pressure that much, but resistance will. Longer tubes and turns in its path are the biggest forms of resistan ce so long as the tube shape and radius are the same.
So no, its not really intercooling the air.
The intercooler will have a much better heat removed:velocity lost ratio. Thats the point of it. This way you get denser air MOVING FAST. you want the air as dense as possible and moving as fast as possible.
like i said. imagine a bridge. X cars at V speed. now double the amount of cars (density) and you will have more cars make it across the brige. Now increase the speed that they travel at and you have even more cars. The STS will probobly have the "cars" move a bit faster but the intercooler will have a MUCH greater density.
Ceramic coating is something they should REALLY look into.
Guys; what a lot of you are missing is that the long pipe
a. hurts in spooling up turbo
b. hurts in getting air to the motor.
a: The exhuast gasses have further to travel so more friction with the walls and hence slow down. they also cool down and get slower so they will spool slower.
b. the piping will be very inefficent at cooling the air. The idea is to cool as much as possible while decreasing pressure as little as possible ( or have as little resistance as possible)
Heat loss wont really effect pressure that much, but resistance will. Longer tubes and turns in its path are the biggest forms of resistan ce so long as the tube shape and radius are the same.
So no, its not really intercooling the air.
The intercooler will have a much better heat removed:velocity lost ratio. Thats the point of it. This way you get denser air MOVING FAST. you want the air as dense as possible and moving as fast as possible.
like i said. imagine a bridge. X cars at V speed. now double the amount of cars (density) and you will have more cars make it across the brige. Now increase the speed that they travel at and you have even more cars. The STS will probobly have the "cars" move a bit faster but the intercooler will have a MUCH greater density.
Ceramic coating is something they should REALLY look into.
05-15-2004, 11:00 PM
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Here are my thoughts.
A: The cooling effect of the exhaust pipe before it gets to the turbo is basically non issue since the turbo is sized with these cooler gasses in mind by changing the A/R. Also the EGT readings of the STS kit are inline with most turbo diesel setups and there is no doubt that those work well. The key to it is changing to a smaller A/R turbine housing. So the cooler gas temp thing doesn't seem to fly. The only thing I couyld even remotely consider is the pressure difference because of the long pipe but once again, as long as the car is running then there is already pressure on the system (pipe).
B. How can you say it is not intercooling the air? If you read 200deg turbo outlet temps and then read 100deg IATs is that not intercooling? CFM is CFM. If the turbo is putting out a certain volume of air then the only way to change the density is by cooling or heating up the air. How can you say that an intercooler is doing this more efficiently then their intake pipe coupled with Alk injection? IMO it's actually less efficient than Alk injection because with any decent amount of boost you will have pressure drop which generally requires you to up the boost which exponentially increases heat.
If I may quote them (STS) with this it will explain it better than I could. It also goes along with stuff that i have read on the GN boards as well.
I am not trying to flame or anything just trying to posts valid arguments.
A: The cooling effect of the exhaust pipe before it gets to the turbo is basically non issue since the turbo is sized with these cooler gasses in mind by changing the A/R. Also the EGT readings of the STS kit are inline with most turbo diesel setups and there is no doubt that those work well. The key to it is changing to a smaller A/R turbine housing. So the cooler gas temp thing doesn't seem to fly. The only thing I couyld even remotely consider is the pressure difference because of the long pipe but once again, as long as the car is running then there is already pressure on the system (pipe).
B. How can you say it is not intercooling the air? If you read 200deg turbo outlet temps and then read 100deg IATs is that not intercooling? CFM is CFM. If the turbo is putting out a certain volume of air then the only way to change the density is by cooling or heating up the air. How can you say that an intercooler is doing this more efficiently then their intake pipe coupled with Alk injection? IMO it's actually less efficient than Alk injection because with any decent amount of boost you will have pressure drop which generally requires you to up the boost which exponentially increases heat.
If I may quote them (STS) with this it will explain it better than I could. It also goes along with stuff that i have read on the GN boards as well.
Testing on our LS1 prototype produced the following results:
Turbo outlet temps at 5 psi boost were 175F and intake temps were 115F which is about 52% efficient.
Turbo outlet temps at 8 psi boost were 225F. This is a 50F increase with only 3 psi added to turbocharger boost. Even most large, expensive intercoolers have a pressure drop of at least 2+ psi. This causes the turbocharger to have to work harder to create 2-3 or even more psi to force the air through the restriction of the intercooler to get that much less boost into the manifold.
So in comparison, with our intercooler efficiency of 50%, combined with virtually no pressure drop, yields in all actuality, a better intercooler efficiency number than the 50% because with a standard pressure drop the temperature difference would be 225F at the turbo and 115F at the intake manifold which would require nearly 70% intercooler efficiency to produce.
And
At 5 psi without methanol, the turbo outlet temps were 175F and intake temps were 115F which is about 50% efficient.
At 8 psi with the Methanol Injection System running, turbo outlet temps were 225F and intake temps were 70F. This is 94% intercooling efficiency.
Turbo outlet temps at 5 psi boost were 175F and intake temps were 115F which is about 52% efficient.
Turbo outlet temps at 8 psi boost were 225F. This is a 50F increase with only 3 psi added to turbocharger boost. Even most large, expensive intercoolers have a pressure drop of at least 2+ psi. This causes the turbocharger to have to work harder to create 2-3 or even more psi to force the air through the restriction of the intercooler to get that much less boost into the manifold.
So in comparison, with our intercooler efficiency of 50%, combined with virtually no pressure drop, yields in all actuality, a better intercooler efficiency number than the 50% because with a standard pressure drop the temperature difference would be 225F at the turbo and 115F at the intake manifold which would require nearly 70% intercooler efficiency to produce.
And
At 5 psi without methanol, the turbo outlet temps were 175F and intake temps were 115F which is about 50% efficient.
At 8 psi with the Methanol Injection System running, turbo outlet temps were 225F and intake temps were 70F. This is 94% intercooling efficiency.
05-15-2004, 11:43 PM
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Originally Posted by F8LPONY
Here are my thoughts.
A: The cooling effect of the exhaust pipe before it gets to the turbo is basically non issue since the turbo is sized with these cooler gasses in mind by changing the A/R. Also the EGT readings of the STS kit are inline with most turbo diesel setups and there is no doubt that those work well. The key to it is changing to a smaller A/R turbine housing. So the cooler gas temp thing doesn't seem to fly. The only thing I couyld even remotely consider is the pressure difference because of the long pipe but once again, as long as the car is running then there is already pressure on the system (pipe).
B. How can you say it is not intercooling the air? If you read 200deg turbo outlet temps and then read 100deg IATs is that not intercooling? CFM is CFM. If the turbo is putting out a certain volume of air then the only way to change the density is by cooling or heating up the air. How can you say that an intercooler is doing this more efficiently then their intake pipe coupled with Alk injection? IMO it's actually less efficient than Alk injection because with any decent amount of boost you will have pressure drop which generally requires you to up the boost which exponentially increases heat.
If I may quote them (STS) with this it will explain it better than I could. It also goes along with stuff that i have read on the GN boards as well.
I am not trying to flame or anything just trying to posts valid arguments.
A: The cooling effect of the exhaust pipe before it gets to the turbo is basically non issue since the turbo is sized with these cooler gasses in mind by changing the A/R. Also the EGT readings of the STS kit are inline with most turbo diesel setups and there is no doubt that those work well. The key to it is changing to a smaller A/R turbine housing. So the cooler gas temp thing doesn't seem to fly. The only thing I couyld even remotely consider is the pressure difference because of the long pipe but once again, as long as the car is running then there is already pressure on the system (pipe).
B. How can you say it is not intercooling the air? If you read 200deg turbo outlet temps and then read 100deg IATs is that not intercooling? CFM is CFM. If the turbo is putting out a certain volume of air then the only way to change the density is by cooling or heating up the air. How can you say that an intercooler is doing this more efficiently then their intake pipe coupled with Alk injection? IMO it's actually less efficient than Alk injection because with any decent amount of boost you will have pressure drop which generally requires you to up the boost which exponentially increases heat.
If I may quote them (STS) with this it will explain it better than I could. It also goes along with stuff that i have read on the GN boards as well.
I am not trying to flame or anything just trying to posts valid arguments.
Turbos ideally are placed very close to the exhuast ports as to try to catch the hottest fastest moving exhuast gasses as possible. Too close can be an issue but it rarely is since you need some sort of routing and some packaging concerns. Close is very important. Diesels also run about 200*(is that the number?) cooler EGT so comparing the two isn't valid.
You dont seem to have a firm grasp on the pressure vs. resistance thing. A longer pipe/tube will create more resistance than a short one of equal cross sectional area/shape. Resistance = loss in pressure/velocity. You are confusing "lag" and "pressure differential."
How can I say it is more efficent?
Heat removed/pressure drop. Like I said; high heat removal: pressure drop is thee goal of any heat exchanger. Also, that pipe is going to be really PO'ed when it has to cool off air at high boost levels whereas an intercooler ill have no problems. And when boost levels get high, you would MUCH rather sacrifice some velocity for cooling which is what the intercooler does and does well. Add water or alcohol injection to an intercooled setup and you are flying.
bottom line: low boost levels and an STS sounds ok. When you really start boosting; its time for a 'real' setup. The STS simply is incapable of cooling the superheated air running through there efficiently. When boost comes to high pressures, the intercooler will shine. I know guys that DAILY DRIVE with 16 psi on an intercooled/water injected setup.
The injection is what is doing the majority of the "saving" in that setup.
I am still waiting to see whos car is going to catch fire and whos turbo is going to crack in the rain/snow.