What kind of supercharger do you all have? I'm very split on where i am going with my vette, but it defiantly needs to throw me in my seat.

if you guys could tell how much it cost you, or how much boost you recieved, or any problems you came across. basically, any information would be helpful

 

I am a big fan of roots blowers. They are simple to install, the visual image is second to none, blower response is instantanous and I get 12 pounds of boost from idle on up.
I also feel it is the simplest of them all to install.
The big downfall is the hole in the hood.
Cost me about $6500CDN for just the blower and carbs. I spend another $3000 on lower the compression and severe duty valves and guides.
It was not cheap but to me it is the best combination I ever had.

 

I'm going with an 8-71 "roots" type on my BB '73 (similar to Norval's). Blower and carbs around $5000.00, engine work $5500.00, plus fuel tank mods, fuel "system" another $1000.00, and on and on it goes.

However, if your motor is in good shape and your compression is not too high, you could just bolt one on and get after it. There are a lot of manufacturers/vendors so there's some good information out there. PLUS, you can't beat input from Norval.

 

Thanks 73 Vet. Honestly I couldn't be happier with the motor. It is brutal and yet very docile if ask. Good gas mileage, about 15 around town, doesn't overheat and gobs of torque from idle on up. Like running on nitrous all the time.
I figure I have no bugs left in the motor.
Now if I can just get the suspension dialed in.

 

I hate stuff sticking out of my hood, not because it doesn't look right but because you can't see the road in front of you, I would install a centrifugal charger before I'd think about a roots blower, also...boost doesn't say everything, if you have a very well flowing intake & healthy cam you can get great numbers w/ low boost, boost just refers to the restrictiveness of the intake tract when forcing a large volume through it in a given time (CFM), more boost for the same system translates to more air getting into the engine, however comparing 2 engines by boost figures is useless until you know the full details on the engine.

 

norval is that an surge tank mounted to your idler pully bracket? how did it work out. by the way i also decided to go with a Roots style 871 for my BBC in my 75. built it from scratch though, never the cheapest way. got aboput $14k invested from the scoop to the oil pan.

 

I've got a twin screw Whipple 3300 on mine (yet to be installed - but close...). Biggest problem at the current time is deciding what exhaust to run which has nothing to do with the S/C...

 

I know boost is not the only thing but if you have a good set of free flowing heads and a healthy boost you are getting more air into the engine.
I know the mustang guys and thier superchargers get almost no boost below 3000. They are rpm related. With my gearing I run in the 1500 to 2000 range all the time and just touch the throttle even at these rpms and you see the boost gage jump right up.
Why did GM go with blowers on the Bonneville?? My wife's car puts out 7 pounds all the time regardless of rpm. Try that with a supercharger.
A big set of heads will not work on the stree, I had them and below 5000 they are useless. A supercharger wouldn't help them at low rpm.
A blower does. It makes them work at 1200 rpm locked in 5th overdrive.
No to me a blower is the best for around town bottom end grunt. Nothing but nothing will beat it on street aplications.
Your turbo, your supercharger are not meant to work in the 1-2000 rpm range. The blower is quit happy down there putting out it's maximum boost even as low as that.
Marck I can pull away from a light , not really pushing the motor and see 10 pounds of boost on the gage.
No I don't like the hole in the hood either but it is the price you pay for a really good street engine with gobs of bottom end.

 

You will find that the blower intake is higher then the rad filler neck. This makes filling the motor a pain. With the surge tank mounted high like this and it won't fit in most applications I can just fill the tank with water and the whole motor is filled. I frequently check the tank and if it is showing water I know the rest of the motor is filled.
I still used the normal overflow from the rad with a 16 pound rad cap. For the surge tank I use a 26 pound cap to prevent water from blowing off from it.
Again this will not clear most hoods. I do not see it with the hood closed.

 

To me that is the BEST system and if not so pricey I would go that route.
Agian I feel nothing works as well as a roots type blower on the street, Nothing.

 

Marck this might not be right but it sticks in my mind.
A little 400 cubic inch normally aspirated engine things it is 400 cubic inches.
Take the same engine and put 14.7 psi boost through it and it thinks it is 800 cubic inches.
While this might not be true I am sure I read it at one time, it stuck in my mind all these years.
I would love to relate head flow taken from 28 inches of vacuum and compare them to pressure readings, in my case I know I have 348CFM at 28 inches with 600 lift. What do I have with 12 pounds of boost????

 

Of course, this ignores friction losses in the intake and the extra hp it takes to run the blower to arrive at a net figure.
This would be a neat test to do sometime. Or perhaps the data is already there and we could get the answers just by analyzing hundreds of different setups and graphing them...

 

No offense...but your reply is so wrong in so many ways.

1. I have a SC'd Buick Regal that is the same setup as your wife's Bonneville...they do not put out 7lbs continuously...if yours does...I would replace the gauge.

2. A supercharger and a blower are the same thing...so I am assuming you are talking about Roots vs. Centrifugal.

3. A turbo is so superior to a blower in EVERY sense. Anyone that says otherwise doesn't have a whole lot of experience with turbos. The biggest advantage a SC has to a turbo is simplicity. The plumbing on a turbo can get hairy...but if you can fit it...then the turbo absolutely will blow doors on a SC'd or a Nitrous car.

 

A normal intake even the good ones loose between 15-25% , that includes flow through the carb. So someone with heads that flow say 300CFM could be down 80 cfm or down to 220 very easily.
With blower the flow goes up, the intake is very short and just plain big runners, that is a dedicated intake for a blower. Mine is just short wide open passages with little flow loss. They are not interested in keeping flow up. The blower does that.

 

No you are right, it doesn't put it out continuously but merging on the expressway, pulling off a light the gage jumps right over and if pushed boarders on the red zone. No blower puts out boost at all throttle positions or the engine would run away with itself.
No boost is instantly there is called upon.

I know superchargers can be anything and the name on my wifes car is superchargered . I refer to blowers as positive displacement and superchargers as belt drive turbo's and turbo's as turbo's.

As for turbo's being superior at everything that might be but I had 2 turbo factory cars and they were not that hot, my friend drives a 2002 turbo Volvo, not that hot and I know what my blower can do at 1200 rpm in 5th lugged right down.
I don't want a turbo because of the plumbing nightmare and under hood temperatures.
I now about all the insulation I could add but it just cluters up the mess of plumbing.

 

It all depends on the car and engine combo. All three power adders you talk about have advantages and disadvantages.roots are instant,turbos are getting quicker and centrifugal are exponential.NOS is tempermental.Power is the easiest to make,getting it to the ground is where all the work is.The prochargers have proven them selves to be very strong power adders,same with turbos and NOS, but nothing looks as sexy as a big roots supercharger on a BB and set up right you can make brutal power and huge instant torque.Add NOS to the roots and you have the efficiency of the best turbos.Properly set up turbos are wicked but as you say the plumbing is a nightmare sometimes.

 

Blown, turbos dont have the instantaneous low end grunt like norval's blower. That is one thing norval has stressed as being important to him several times. I frequently read the ls1tech and see what the crazy fbody people are doing. The turbo guys put out unimaginable power, 700rwhp and up. Yet the nitrous guys are running better times with less power. I am not saying nitrous is better for the 1/4 or anything, but it has me wondering; are the nitrous guys just more dedicated on learning how to drive their cars and setting up their suspension?

Dang you big632, you beat me!

 

Well - you just gave us the main reason turbos aren't superior in EVERY sense. The plumbing is a nightmare (and expen$ive) especially if you are working in small spaces such as Vettes and where heat in the engine compartment is a pain.

Another area where they aren't superior is at lower engine speeds - the positive displacement types are boosting right off idle. While the turbo guy is waiting for the boost to cut in, the roots guy has already found a parking place at the drive-in a couple of miles down the road, and is talking to chicks.

Let's check another area...hey! Look at all the turbo setups...
http://www.nhra.com/2005/events/race...iday/index.htm

 

turbos are nice, but between the plumbing, the heat and the looks i decided on a jimmy.

 

Why did GM go with blowers on the Bonneville?? My wife's car puts out 7 pounds all the time regardless of rpm. Try that with a supercharger

Guys I didn't mean this like it sounds, No car can run on boost all the time regardless of rpm. What I mean is weather you are reving 1000 rpm or 4000 or 5000 rpm the available 7 pounds boost is right there. Rpm means nothing. Throttle position is everything. If the throttle is open the blower is getting the air needed and on the very next turn of the engine full boost is rammed in. There is absolutely no lag , no lack of boost because of rpm and no complicated hookup.
I'm never sorry about my choice of power adder. Streetability means everything as does street friendly gearing, gass mileage, maners and bottom end. Most of my driving is under 2000 with my 308 gearing and .68 overdrive. 411's slow the car down because of too much torque and no street traction.
The 308's allow the car to finally start hooking in 3rd gear.