skav said:
What makes the Whipple/screw more efficient than a roots straight lobe? Is it just a newer, better design? Both are available with intercoolers so heat shouldn't be an issue. Would it be correct to call a roots setup "old school"?
I get the whole efi computer deal. My Whipple and mefi is super mellow-if that's the right way to describe it.
It always fires right up and idles at 850 with no surge.
Click here to get more.
Click to expand...
Screw Superchargers are actually an air compressor which is more adiabatic efficient than a Roots Supercharger. A Roots supercharger, which most originated from a 2 stroke diesel engine, typically a Detroit ie; 8-71 (8 cylinder, 71 cubic inches per cylinder). Centrifugal superchargers are kind of a cross breed between turbos and Screw or Roots Superchargers. All of these are mechanically driven.
Turbo Chargers work primarily on the Radiant Heat/Expansion of exhaust gases not so much exhaust pressure or back pressure. In a Diesel engine they work perfectly. However with a gasoline engine they can cause a snowball effect once the engine fuel/air ratio goes lean as it will case more radiant exhaust heat which will spool the turbo to make more boost which will only further lean the engine, and so on.
All types of supercharging used to increase the volumetric efficiency of the engine which will raise the power output or Brake Means Effective Pressure.
Here are a couple of links that you should find interesting. All of them are pretty basic and short reads but will give you a better understanding of what you are asking about.
Hope this helps.
http://www.superchargersonline.com/index.php?main_page=page&id=12
https://en.wikipedia.org/wiki/Turbocharger
http://kennebell.net/KBWebsite/Common/pdfs/SC_efficiency.pdf
Screw Superchargers are actually an air compressor which is more adiabatic efficient than a Roots Supercharger. A Roots supercharger, which most originated from a 2 stroke diesel engine, typically a Detroit ie; 8-71 (8 cylinder, 71 cubic inches per cylinder). Centrifugal superchargers are kind of a cross breed between turbos and Screw or Roots Superchargers. All of these are mechanically driven.Turbo Chargers work primarily on the Radiant Heat/Expansion of exhaust gases not so much exhaust pressure or back pressure. In a Diesel engine they work perfectly. However with a gasoline engine they can cause a snowball effect once the engine fuel/air ratio goes lean as it will case more radiant exhaust heat which will spool the turbo to make more boost which will only further lean the engine, and so on.All types of supercharging used to increase the volumetric efficiency of the engine which will raise the power output or Brake Means Effective Pressure.Here are a couple of links that you should find interesting. All of them are pretty basic and short reads but will give you a better understanding of what you are asking about.Hope this helps.
If you want to learn more, please visit our website Benyuan.
Post
by BrazilianZ28Camaro » Fri Dec 23, 2011 1:33 pm
Since just about everyone here in Brazil is stuffing a GMC blower on their V8 engines, I'm trying to resist the temptation. This is why:
Based on the cost, the added weight and rotational mass of the blower, I'll go with a stroked SBC N/A. But I'll admit I luv the blower looks.
But the most important to me is make the Z28 go fast. So I figured that the majority of the USA build ups are N/A for power ranges from 500 to 700 hp.
These power ranges would be easier to achieve with a blower or nitrous, but the majority of V8s still are hot N/A setups, as I see.
We know the blower is a torque builder, so the question is, how can a 600hp SBC N/A compare to 700hp blower small block, keeping in mind the N/a Car might be 120lbs lighter, have about 30lbs less parasitic rotational mass on the engine and nothing to eat up hp to compress the air.
Then this topic is to you Speedtalkers comment why go for the blower and why not . "Scientific" or "learned over the years" opinions are very welcome.
Thanks for replies!
Hello friendsSince just about everyone here in Brazil is stuffing a GMC blower on their V8 engines, I'm trying to resist the temptation.This is why:Based on the cost, the added weight and rotational mass of the blower, I'll go with a stroked SBC N/A. But I'll admit I luv the blower looks.But the most important to me is make the Z28 go fast. So I figured that the majority of the USA build ups are N/A for power ranges from 500 to 700 hp.These power ranges would be easier to achieve with a blower or nitrous, but the majority of V8s still are hot N/A setups, as I see.We know the blower is a torque builder, so the question is, how can a 600hp SBC N/A compare to 700hp blower small block, keeping in mind the N/a Car might be 120lbs lighter, have about 30lbs less parasitic rotational mass on the engine and nothing to eat up hp to compress the air.Then this topic is to you Speedtalkers comment why go for the blower and why not . "Scientific" or "learned over the years" opinions are very welcome.Thanks for replies!
Roots vs screw? And blower vs turbo questions
skav said:
What makes the Whipple/screw more efficient than a roots straight lobe? Is it just a newer, better design? Both are available with intercoolers so heat shouldn't be an issue. Would it be correct to call a roots setup "old school"?
I get the whole efi computer deal. My Whipple and mefi is super mellow-if that's the right way to describe it.
It always fires right up and idles at 850 with no surge.
Click to expand...
Screw Superchargers are actually an air compressor which is more adiabatic efficient than a Roots Supercharger. A Roots supercharger, which most originated from a 2 stroke diesel engine, typically a Detroit ie; 8-71 (8 cylinder, 71 cubic inches per cylinder). Centrifugal superchargers are kind of a cross breed between turbos and Screw or Roots Superchargers. All of these are mechanically driven.
Turbo Chargers work primarily on the Radiant Heat/Expansion of exhaust gases not so much exhaust pressure or back pressure. In a Diesel engine they work perfectly. However with a gasoline engine they can cause a snowball effect once the engine fuel/air ratio goes lean as it will case more radiant exhaust heat which will spool the turbo to make more boost which will only further lean the engine, and so on.
All types of supercharging used to increase the volumetric efficiency of the engine which will raise the power output or Brake Means Effective Pressure.
Here are a couple of links that you should find interesting. All of them are pretty basic and short reads but will give you a better understanding of what you are asking about.
Hope this helps.
http://www.superchargersonline.com/index.php?main_page=page&id=12
https://en.wikipedia.org/wiki/Turbocharger
http://kennebell.net/KBWebsite/Common/pdfs/SC_efficiency.pdf
Screw Superchargers are actually an air compressor which is more adiabatic efficient than a Roots Supercharger. A Roots supercharger, which most originated from a 2 stroke diesel engine, typically a Detroit ie; 8-71 (8 cylinder, 71 cubic inches per cylinder). Centrifugal superchargers are kind of a cross breed between turbos and Screw or Roots Superchargers. All of these are mechanically driven.Turbo Chargers work primarily on the Radiant Heat/Expansion of exhaust gases not so much exhaust pressure or back pressure. In a Diesel engine they work perfectly. However with a gasoline engine they can cause a snowball effect once the engine fuel/air ratio goes lean as it will case more radiant exhaust heat which will spool the turbo to make more boost which will only further lean the engine, and so on.All types of supercharging used to increase the volumetric efficiency of the engine which will raise the power output or Brake Means Effective Pressure.Here are a couple of links that you should find interesting. All of them are pretty basic and short reads but will give you a better understanding of what you are asking about.Hope this helps.
The truth about roots blowerroots blower? - Don Terrill's Speed-Talk
Post
by BrazilianZ28Camaro » Fri Dec 23, 2011 1:33 pm
Since just about everyone here in Brazil is stuffing a GMC blower on their V8 engines, I'm trying to resist the temptation. This is why:
Based on the cost, the added weight and rotational mass of the blower, I'll go with a stroked SBC N/A. But I'll admit I luv the blower looks.
But the most important to me is make the Z28 go fast. So I figured that the majority of the USA build ups are N/A for power ranges from 500 to 700 hp.
These power ranges would be easier to achieve with a blower or nitrous, but the majority of V8s still are hot N/A setups, as I see.
We know the blower is a torque builder, so the question is, how can a 600hp SBC N/A compare to 700hp blower small block, keeping in mind the N/a Car might be 120lbs lighter, have about 30lbs less parasitic rotational mass on the engine and nothing to eat up hp to compress the air.
Then this topic is to you Speedtalkers comment why go for the blower and why not . "Scientific" or "learned over the years" opinions are very welcome.
Thanks for replies!
Hello friendsSince just about everyone here in Brazil is stuffing a GMC blower on their V8 engines, I'm trying to resist the temptation.This is why:Based on the cost, the added weight and rotational mass of the blower, I'll go with a stroked SBC N/A. But I'll admit I luv the blower looks.But the most important to me is make the Z28 go fast. So I figured that the majority of the USA build ups are N/A for power ranges from 500 to 700 hp.These power ranges would be easier to achieve with a blower or nitrous, but the majority of V8s still are hot N/A setups, as I see.We know the blower is a torque builder, so the question is, how can a 600hp SBC N/A compare to 700hp blower small block, keeping in mind the N/a Car might be 120lbs lighter, have about 30lbs less parasitic rotational mass on the engine and nothing to eat up hp to compress the air.Then this topic is to you Speedtalkers comment why go for the blower and why not . "Scientific" or "learned over the years" opinions are very welcome.Thanks for replies!