STS vs Intercooled turbo and pressure drops.
05-13-2004, 01:29 AM
#11
I know you understand the concepts that you are talking about, but let me clarify this.
Air pressure and the velocity at which that air is traveling are two different things. I think if you just say "air" instead of "pressure velocity" it clears up what you are saying. Also, pressure cannot cool down. However, materials with fluid like characteristics, such as air or liquid, will have lower pressure with lower temperatures. And when air cools, the molecules get closer together=more dense. The closer the air molecules are to eachother the less pressure the air will have.
Here is why 9 intercooled psi of boost can make more power than 15psi of boost. In a combustion engine it is the Mass of intake air that makes power not the Volume. When air volume increases, the density of the air decreases. In the engine the compressed air must occupy a given amount of space. If you increase the volume of air in this given amount of space (boost) this creates a by-product of heat because of increased pressure. Heat effectively decreases the density of the air. This is when the equation of Mass = Density x Volume is handy.
The goal is to create more air Mass - not just volume. The higher the density, the lower the volume. You can see how this works by rearraging that simple equation. The mass of air forced into the engine only becomes beneficial when the volume of air is higher than the decrease in density. In order to counter the heat factor, you must find a way of cooling the air, which increases the density. This can be accomplished with the use of an intercooler.
Someone needs to look up some stuff by Corky Bell. He explains this stuff Really well.
Originally Posted by speedhoe04
"...but what it does mean the density of the pressure velocity drops the longer you go thru the piping. Now when you place an intercooler in the mix, the pressure cools down expanding the pressure therefore making the pressure denser; so now you got a cooler denser pressure velocity going to your engine vs a hotter less dense pressure velocity going to your engine."
Here is why 9 intercooled psi of boost can make more power than 15psi of boost. In a combustion engine it is the Mass of intake air that makes power not the Volume. When air volume increases, the density of the air decreases. In the engine the compressed air must occupy a given amount of space. If you increase the volume of air in this given amount of space (boost) this creates a by-product of heat because of increased pressure. Heat effectively decreases the density of the air. This is when the equation of Mass = Density x Volume is handy.
The goal is to create more air Mass - not just volume. The higher the density, the lower the volume. You can see how this works by rearraging that simple equation. The mass of air forced into the engine only becomes beneficial when the volume of air is higher than the decrease in density. In order to counter the heat factor, you must find a way of cooling the air, which increases the density. This can be accomplished with the use of an intercooler.
Someone needs to look up some stuff by Corky Bell. He explains this stuff Really well.
05-13-2004, 05:33 PM
#15
On The Tree
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i never said the sts kit is a waste, in fact its a great kit.
all i am saying is that the idea behind the sts kit has alotttttttt more pontential.
its an answer to a truck who wants a turbo, doesnt mean its the best or the worst.
think of it this way, the sts kit is the lower kit of the bunch that are available or going to be.
if you inspect the kit thoroughly, you will see certain things they could of done better, exhaust joints, coatings, scavenge pump to name a few.....my most important factor is the turbo sizing. i think its small for our engines. but thats my gander.
overall the kit has excellent merits, phenomenal idea and most of all it works! thats more then i can say for others who have tried to put a turbo on a measly s10.
all i am saying is that the idea behind the sts kit has alotttttttt more pontential.
its an answer to a truck who wants a turbo, doesnt mean its the best or the worst.
think of it this way, the sts kit is the lower kit of the bunch that are available or going to be.
if you inspect the kit thoroughly, you will see certain things they could of done better, exhaust joints, coatings, scavenge pump to name a few.....my most important factor is the turbo sizing. i think its small for our engines. but thats my gander.
overall the kit has excellent merits, phenomenal idea and most of all it works! thats more then i can say for others who have tried to put a turbo on a measly s10.
05-13-2004, 06:09 PM
#18
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Originally Posted by agreif
This is the kit that has the turbo back by the rear axle correct?
05-13-2004, 07:09 PM
#19
TECH Junkie
I think the alcohol injection is responsable for a lot of the STS turbo kit's ability to tolorate 15lbs of boost.An alcohol fueled motor will run much cooler combustion temps because the vapororization and flash points are much lower than gasoline,if you run straight alcohol you find that it takes twice fuel mixture to run your engine.Indy cars can run huge amounts of boost running straight methanol without fear of detonation or overheating.If your STS setup runs out of alcohol at 15psi of boost the stock internals in your 5.3 will melt down almost instantly,I hope you have a good way to monator your alcohol system if you are running it on the street.I'd love to see some track times on the setup.Hows the drivability?Does turbo lag get worse as the boost increases?Nice numbers,congrats.
05-14-2004, 02:34 PM
#20
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You might put an intercooler in place of one of the charge pipes that run along the outside of the frame. It wouldnt be very big, but could be done.
As far as running out of methanol. Some people are using the washer reservoir so that it says " low washer fluid " when getting low.
Driveability is great. My car drives completely stock until you get on it. It hits full boost at 3000. (6 speed Formula, completely stock). Gets better gas mileage.
As far as running out of methanol. Some people are using the washer reservoir so that it says " low washer fluid " when getting low.
Driveability is great. My car drives completely stock until you get on it. It hits full boost at 3000. (6 speed Formula, completely stock). Gets better gas mileage.