I have no experience in supercharging LS engine and I wan't to know about differences between centrifugal and roots/lysholm-type superchargers when bolted to LS1.

1. My goal is to have instant power as low as <2000 rpm.

2. Brake hp should be around 500.

3. Low maintenance and a possibility to increase power later without changing every (expensive) part of the system.

4. Basic system must be emission legal at least in some states (I could change parts of the system after inspection.. We have odd laws here in Finland)

How about those KB and Magnachargers, are they up to this challenge? How about the boost pressure with those? I think 10 psi will be enough for stock LS1? Can you change the drive ratio with those "Eaton"-type superchargers without getting too high RPM for the unit?

How about those centrifugal units? How low RPM they generate boost and do they have a lag when opening the throttle suddenly (while cornering on track for example).

I need a system which is easy to control with your right foot during cornering on track on sundays. I don't have enough money for LS7..

 

KB is what you need they give crazy power /tq down low, it is instant...

 

Simple,

Go Maggie.

 

Well, I was going to say KB (your welcome Jeff) until you mentioned track days.

Since you also want a kit to grow into without upgrading, I would go with the ECS kit.

http://eastcoastsupercharging.com/SC600.html

 

If you want the power down low, Positive Displacement is the only way I know how to get it. While I don't yet own a supercharged car, I've been doing heavy research for a while now.
I would say most guys on this forum run a Centrifugal set-up, but I don't think it will give you the instant boost/power at the low RPM levels you desire.
I posted up a thread entitled "Forced induction at the track" a little while ago if you would like to read that. Most of the posts I got tried to shy me away from doing forced induction. Normaly aspirated is better on a road course mainly because of reliability and the high temps associated with supercharging. Therefore if you track a lot, maybe doing a heads and cam set-up might be better for you. This way you could get close to the power levels of an LS7 without spending all the money.
If you're stuck on Supercharging (like I am), then a positive displacement SC is the way to go for your power requirements. Go with a Magnacharger, or Kenne Bell, or Dragon Racing. The Kenne Bell has the highest potential for big numbers (600hp+), but you will probably pay a little more. With either the KB or Maggie, you will need to change your hood as well, so keep that in mind. I think there is also an Eaton or Whipple kit, can't remember which at the moment. Don't count out a Centrifugal all together, while it wont give you lots of boost/power down low, they are still good kits, and in my research I've some across a few guys running them on the track succesfully.
The biggest problem you will run into with Supercharging is heat. Putting an intercooler in front of your radiator will raise engine coolant temps significantly. If you go this route you will probably have to upgrade your radiator. With a PD SC the air charge is cooled via an air/water intercooler which I believe would give some flexibility with mounting location. Perhaps running multiple heat exchangers, or just packing ice around the reserviour when at the track. Which is about where I'm at with my research and decision making. Hope this helped at least a little. Good luck!

 

I don't know how many times I can say this...

It doesn't matter if the roots style superchargers give you more bottom end torque, it is NOT USEABLE. The guys, including me, with the centrifugal type can step on the gas pedal at idle and spin the tires until they blow up, what would more low end toques do for us, or you? You want more torque/hp at the top end where you can use it.
The real question is:
Do you want to go fast, or have your engine bay look pretty?

 

After reading your post again, I realized my very lengthy post didn't answer all your questions.
10#'s of boost is more than enough for a stock LS1. Most people run 7-9#'s on a stock bottom end. If you're tracking it, I would stay around 6-8#'s, because the engine will be working pretty hard. I'm sure you don't want to risk breaking it.
As for changing pulleys on a PD blower, you can adjust boost effectively that way. Check out the Kenne Bell website. They have some nice technical graphs that demonstrate how boost changes with pulley changes:

http://www.kennebell.net/supercharge...gmCorvette.htm

As per your term "brake horse power", I take that to mean "at the block". A stock LS1 should be safe to around 520hp at the TIRES (give or take 50hp LOL). You will want a fairly conservative tune, as you will be pushing her hard at the track. Any of the SC options I mentioned above will give you those power levels.
I believe the Magnacharger is 50 state legal (emmisions). I think the Kenne Bell is too, but I'm not sure.
There is no "lag" associated with a Centri. If you have the engine at higher RPM (about 3500+), you will be "in" the boost instantly.
Sorry my posts are so lengthy, I'm pretty long-winded when typing I guess.

 

Then why do PD guys leave Centri guys in the dust "light to light"?

Low end and mid is VERY USABLE on the street and road courses.

If you are looking for peak # bragging rights then go centri.

 

And the Internet at its best again!

People who have no experience with superchargers giving advice.

 

I realize I haven't run a SC on my car. I was just trying to convey some of what I've learned by doing my own research. I think what I have posted is helpful information, if my info is incorrect, please let me know. I would like to know if I'm under the wrong impression so I don't make any decisions based on false pretenses.

 

So they just produce peak numbers, no track times to back up the numbers?

 

See if you can find some local guys that are supercharged and go for a ride in the cars...

 

I'm just wishing there was someone that lived near me, so I could get a ride.

 

No lag, and easily modulated, but you'll probably only have about 2 pounds boost at 2000 rpm, if that matters. Not sure why your rpm would ever be that low at the track.

Where the low end grunt of the PDs excels is for "drifting".

 

you must be talking about street racing from stop light to stop light... I wouldn't know much about that, the only 'lights' I know of is the tree at the track, and the PD's are the ones left behind there.

best advice so far.

Because our bodies can measure changes in acceleration much better then PEAK acceleration, it will 'feel' like a PD blower is faster then a centri, but track times/lap times will tell a different story.

 

Ask if anyone has a blower setup near you in Mountain - Prairie section...

 

Thanks for these replies this far.

I have made a car with Eaton PD before. It was a Beamer E30 4wd 2500 cc and the result was like driving a standard car but with less effort. The power curve was a bit higher than stock all the way from idle to max RPM. That power was usable, like driving a N/A but with more power.

I wonder if there's major differences between KB and Maggie? Do they use same Eaton unit or do they make their own units? Cutting the hood is not a problem and water circulation with cooler for it is a piece of cake.

Proper heads, cam and intake would suite my purposes more than SC but after spending €'s to those the limit for max power is near and the step up would need the SC anyway.. I'm hoping to get N/A behaviour, with LS7 (or more) potential.

 

Thanks for making me laugh

 

Not being a SC guy but rather nitrous dude,these are my thoughts (facts) based on competition.

A Roots type supercharger has a great bling affect and provides a nice upgrade in power for street type applications. However,when it comes to actual performance I consider the Roots (PD) superchargers as being non competitive...no fear of being beaten...very limited potential for producing high out put numbers that can be relevant to track performance.

Now on the other hand the centrifugal supercharger doesn't have the great bling affect of the PD supercharger,but still looks good in my opinion. The centrifugal supercharger can and does have a great potential for producing high out put numbers that are performance (track) proven. So when lining up against a centrifugal supercharged car you know that the potential for a good race is always present.

So being a true gear head the only supercharger for me (if I were to change from nitrous)would be the centrifugal unit...I'm not really a bling guy...but cool for others if that's what you dig.

 

Because you didnt accelerate fast enough to get their attention