[QUOTE=parish8]nice numers whitt. do you happen to have a chart for that? i would love to see it.

Parish,I had a stack of charts when I picked up the truck.The guys were just using the charts to make tuning changes.I didn't even plan to post them at all.The horsepower figures kind of leaked out by word of mouth and found there way here,I was put in a position of confirming or denighing the numbers.The motor is probably good for 550 or more rwhp without the supercharger or about what your 408 would make NA.

 

[QUOTE=whitt1]Whitt I wanna hear more about your 402, did you stroke a 6.0, where did you get the kit or did you buy it allready built, heads, cam?

Would you rather have turbo or SC

 

Im going with a Master Power t-70 intercooled... running 9-10lbs of boost..

Parish Actually.... I just bought your old Manifold!!!

 

matt, here is alink to some pic's of what you might need to finish that project >> http://www.neufamily.org/03html/pics...pics/index.htm. you got the hardest part there but there is still a lot of fabing up to do.

 

Ive got about 5 month haha Bachelor of science mmmmmmmmmmmmmm bitches

Ok now back to turbos what is the correct size turbo for a 5.3 with a moderate cam and heads say you wanted max boost and power at 3500 looking for 600+ at the wheels.

 

A T76.

 

Radix:
A common, but perhaps more correct, term for a Roots supercharger is "blower". One defining characteristic of a Roots is that charge air compression occurs outside the supercharger, in the space between it and the intake valves. In effect, it blows air into the intake manifold where it becomes compressed due to the system's pushing more air in than can flow out.

The Roots blower was patented in 1860 by two brothers, Philander and Francis Roots, as a ventilating device for blast furnaces, grain elevators and coal mines. In the last half of the 19th century they were quite common in those applications and that ancestry is key to understanding that a Roots is a device which moves air rather than compresses it.

In the early part of the 20th Century, engineers perfected supercharging in motorsports and aircraft applications using primarily centrifugal superchargers. In the '30s, Roots blowers gained acceptance in Grand Prix and Indianapolis racing and on some expensive, high-performance sports cars of the period. Starting in the late-'30s, General Motors began using large Roots blowers on the diesels it built for its GMC heavy-duty trucks, its marine customers and its Electromotive Division locomotives. In the 1950s, drag racers and Bonneville Salt Flats competitors adapted GMC blowers to racing engines. Today, Roots blowers are still quite common in motorsports, especially drag racing.

The Magnuson "Radix". Magnuson makes both the intake manifold and the blower case. The drive and the guts of the blower are Eaton parts used in Eaton's model-M112 supercharger, the largest unit Eaton makes for O.E.s.

Later, the Roots idea transferred to the street high-performance aftermarket and the Eaton Corporation developed a small, compact Roots blower for original equipment use on some performance cars, luxury sedans. Buick, Pontiac, Ford, Lincoln, Jaguar and Mercedes Benz are just a few brands using the Eaton blower, the design of which is now in its fifth-generation.

The rotors from the fifth-generation Eaton supercharger have a frosty-looking, matte-black color, this is the APC with partially-abrades away during break-in leaving an enhanced lobe-to-lobe seal. The lobes mesh as they turn and that pulls the air through the supercharger.

There are some concerns with blowers and one is cost. A properly developed, aftermarket supercharger kit runs several thousand dollars. Add installation labor and you're past five large pretty quick. Because a supercharger increases both the engine's cylinder pressure and charge air temperature, two causes of detonation or "knock", blowers mandate use of at least 91-octane fuel which may increase operating cost. A "boosted" engine produces a higher volume of exhaust gases, so engines equipped with superchargers usually need a low-restriction exhaust system.
With aftermarket superchargers on computer-controlled engines, the "calibration" in the computer, software which tells the computer how to set the fuel curve, spark curve, emissions controls operation and a host of other operational parameters, can be a significant development issue. In fact, proper engine controls calibration of a aftermarket supercharger system requires almost as much work as developing the supercharger hardware, itself, so a key factor in the difference between a good aftermarket blower kit and a bad one is, often, calibration. Lastly, don't be surprised if there is a reduction in fuel economy. How much depends on how the engine is driven. If boosted operation is infrequent and the blower has a bypass (which we'll discuss momentarily), fuel mileage will be close to stock. If you're "on boost" regularly, expect a noticeable decrease in mileage.

The word "Radix" is Latin for "root" or "origin," an appropriate name, indeed. Radix are based upon Eaton, fifth-generation, M112 superchargers but they're not simply "rebadged" Eatons. Magnuson uses many of Eaton's internal pieces but manufactures its own supercharger case, intake manifold, charge air cooler and drive system.

What actually moves the air through a Roots blower is a pair of contrarotating, tri-lobe rotors which mesh as they turn. The tighter the fit of the lobes, the more efficient the blower is, however, there must be some clearance or the rotors won't turn. If the clearance is too great, the supercharger is inefficient because of leakage past the lobe edges. If the clearance is too tight, there is a high level of resistance to rotation. To both tighten rotor clearance and reduce friction, one trick Eaton began using with its fifth-generation Roots is to coat each rotor with an abradable powder coating or (APC). During the break-in period, in the first few hundred miles of operation, a small portion of this coating abrades away, leaving the contact areas at the tips of the rotor lobes perfectly matched to each other and able to run extremely close.

Eaton rotors are twisted 60 degrees. Helical rotors, along with specially designed inlet and outlet port geometry in the blower case, help to reduce pressure variations resulting in a smooth discharge of air and a lower level of noise during operation. This arrangement, also, improves efficiency. With helical rotors, the supercharger can run at up to 14,000 rpm ( current spec ), making for a small blower for a given boost and air flow output. The Eaton's axial intake further reduces package size.

Another "secret of the Radix" its bypass valve. This small valve, between the the throttle body and the intake manifold, increases fuel economy and reduces parasitic power loss. The bypass is operated by a vacuum actuator and is normally closed. When manifold pressure is low (high vacuum typical of light throttle operation) the actuator opens the valve, allowing charge air to flow from the throttle body directly into the intake manifold, bypassing the blower and equalizing pressure in the system. The bypass valve open at low manifold pressure eliminates parasitic loss in a practical sense. Magnuson superchargers running with an open bypass consume only about one horsepower. When the supercharger begins to make boost, the bypass valve snaps closed, allowing pressure to build in the intake ports.

All Radix have a "charge air cooler" (until recently) which some call an intercooler. During compression, charge air temperature rises. Because a temperature increase reduces air density, negating some of the effect of compression, and makes the engine more prone to detonation; there is an advantage in cooling the air after it exits the blower but before it goes into the cylinders. The Radix charge air cooler is built into the intake manifold.

 

furthermore IMO:

The current modified roots type is the best type of supercharger to use until the boost pressure exceeds 13-15 PSI. At that point the pressure in the manifold starts to exceed the pressure in the supercharger housing and it starts to backflow into the supercharger and decreases its output and the heat generated really goes up. Above 13-15 PSI the better supercharger would be the Lysholm type. It is known that the compression of air occurs in the plenum after it leaves the supercharger in the modified roots type supercharger unlike the Lysholm where the air is compressed inside the blower and then decompresses as it leaves the blower and enters the plenum. The advantage with the modified roots type is that it has less parasitic drag on the engine when boost is not needed. The Eaton superchargers also use a bypass valve that equalizes the pressure on both sides of the impellers when the engine is operating in vacuum. This takes more load off the engine and reduces the heat generated in non-boost conditions. The Lysholm is still compressing air internally even during non-boost conditions and this generates heat and has more parasitic drag on the engine during any non-boost condition, even with a bypass valve. Mercedes Benz does use some Lysholm superchargers on their super cars and they employ a clutch to disengage the supercharger from the crank shaft during non-boost conditions to counter the negatives of the Lysholm superchargers.

Overall the modified roots type supercharger is the much better choice if you are staying under 13-15 PSI of boost. This is why most of the OEM's choose the Eaton modified roots type superchargers for their production cars.

 

OK, We always hear about the Radix/Roots supercharger's main weak point right? "Heat". Specifically, heat at higher boost levels. You will see the HEAT issue come up in almost every case of FI, unfortunetly it is the nature of the beast, so to speak. I just want to be clear though, heat is not just a Radix issue, it is universal. So what about the Twin Screws main weak point? "Off Boost Conditions". Specifically, The Twin Screw is compressing air internally even during non-boost conditions and this generates heat and has more parasitic drag on the engine during these non-boost times(i.e. daily driving), even with a bypass valve. Now, thinking about this logically, do you really think when sitting at idle (i.e. off boost) that the Twin Screw supercharger is able to overcome its biggest disadvantage fast enough to build boost quicker than a modified roots/radix supercharger does in its most ideal condition? Meaning, off idle, a modified roots, only has productive boost to build, while a Twin Screw, has to overcome its biggest drawback before producing productive boost.
Hence, the reason Mercedes Benz does use some Twin Screw (Lysholm) superchargers on their super cars and they employ a clutch to disengage the supercharger from the crank shaft during non-boost conditions to counter the negatives of the Lysholm superchargers.
Lastly, on daily driven vehicles, how often are we at an "Off Boost Condition"? 90% of the time, like when we come to a stop light, idle, or have to slow down for traffic, cruising on the highway.

thats it for now, more to follow

 

yep, t76.

if you have a hp goal then it is prety easy to work backwards from there and pick a turbo.

a t76 is rated at 950fwhp, then hit it with the 25% driveline losses and you are at about 700rwhp. if you are sure you would be happy at exactly 600rwhp then you could go smaller to try and get it to spool quicker, a t70 is rated at 840fwhp - 25% and you are a little over 600rwhp. i would just get the t76.

i dont have a lot of experience with diferent size motors and diferent size turbos. i wish i had more. my t76 on the 6.0 was just a little laggy. on the 408 it was just silly with no lag at all. then it was on the 4.8 for a little while and there was some definate lag but you could build a lot of brake boost with the little motor where the truck would pull itslf off the line with the bigger motors if i tried that.