Roush charger in a auto?

Five Oh Brian

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with 4.6 liters, 281 cubic inches these motors are a bit smaller than the 5.7 Chrysler and the 6.2 chebbie and make less torque. Torque moves weight. Typically a roots type blower makes more torque lower in the rpm range where the butt dyno can feel it.

is it better ? For the broadest spectrum of drivers probably. Everybody talks about horsepower but really it's the torque you feel when accelerating from low rpms. But as this is a forum where most owners have specific goals in mind ie; drag racing, street racing, autocross or road racing 'better' is too broad a term. I used better for the general population I guess since most people who drive their cars day to day and do not race will benefit from more power down low.

I totally agree that torque is what gets a mass in motion, and that horsepower is simply torque applied over time. Basic physics. The old saying is that "horsepower sells cars & torque wins races."

However, my 07 GT with its paltry 281 cubic inches and non-intercooled standard Vortech V2 seems to defy physics. On a Mustang dyno, it put down 364 rwhp and only 303 rwtq. Yet, it runs 0-60 mph in 3.7 seconds (on par with many exotic cars). 60' times at the dragstrip are in the 1.7's consistently. My 1/8 mile is in the mid 7's @ 90 mph. 0-100 mph comes up in the mid 9's. My best 1/4 mile run was an 11.85 @ 112. So, I have less torque than most N/A S197's, yet I'm running ET's that are as good as (or better) than a stock GT500 which makes about 180 more rwtq than my car. So, a centrifugal blower can accelerate a heavy car like our S197's just as well as a roots blower.

Now on the flip side, my butt-o-meter says my car isn't fast. It is incredibly deceiving. A roots car "feels" quicker than my centri, but the timeslips don't lie - only my senses. That's mostly due to the roots blower packing a huge punch at low rpm, but plateauing after that; while a centri starts off mild, yet progressively & linearly builds boost as rpm's climb.

So, if you want to "feel" like you have a fast car, get the roots. If you don't mind feeling slower than you really are, the centri is a very cheap entry into the world of forced induction.

Ultimately, there are NO bad blowers for our cars. Just different good alternatives. All of which can be tuned and pullied to make more power than the stock bottom end can handle anyway.
 

Alter Ego Trip

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Ultimately, there are NO bad blowers for our cars. Just different good alternatives. All of which can be tuned and pullied to make more power than the stock bottom end can handle anyway.

Well said.

On a side note, your car is not defying physics. You ran on a very conservative dyno. Doesn't mean that's all she's got, just all the dyno showed. ;)
 
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Germeezy3

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I totally agree that torque is what gets a mass in motion, and that horsepower is simply torque applied over time. Basic physics. The old saying is that "horsepower sells cars & torque wins races."

However, my 07 GT with its paltry 281 cubic inches and non-intercooled standard Vortech V2 seems to defy physics. On a Mustang dyno, it put down 364 rwhp and only 303 rwtq. Yet, it runs 0-60 mph in 3.7 seconds (on par with many exotic cars). 60' times at the dragstrip are in the 1.7's consistently. My 1/8 mile is in the mid 7's @ 90 mph. 0-100 mph comes up in the mid 9's. My best 1/4 mile run was an 11.85 @ 112. So, I have less torque than most N/A S197's, yet I'm running ET's that are as good as (or better) than a stock GT500 which makes about 180 more rwtq than my car. So, a centrifugal blower can accelerate a heavy car like our S197's just as well as a roots blower.

Now on the flip side, my butt-o-meter says my car isn't fast. It is incredibly deceiving. A roots car "feels" quicker than my centri, but the timeslips don't lie - only my senses. That's mostly due to the roots blower packing a huge punch at low rpm, but plateauing after that; while a centri starts off mild, yet progressively & linearly builds boost as rpm's climb.

So, if you want to "feel" like you have a fast car, get the roots. If you don't mind feeling slower than you really are, the centri is a very cheap entry into the world of forced induction.

Ultimately, there are NO bad blowers for our cars. Just different good alternatives. All of which can be tuned and pullied to make more power than the stock bottom end can handle anyway.

You also have a big stall and an automatic transmission which eats up a lot of the " show " horsepower but as your numbers suggest you have plenty of " go " horsepower. The centri actually gives your tires the change to hook up and make the most of your trap speed. Your running almost a full second faster than the new 5.0's which trap close to the same as you do.
 

Germeezy3

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The M90 is perfect for a street driven car, that the owner never plans on pushing much past 450 rwhp and ocassionally drives fast. For a track car or drag car the heat soak, soaring IAT's and generally bad adiabatic efficiency of a roots blower is not such a good proposition. The TVS blower with their lobe design seem to be the best at some of the bad issues compared to their peers.

The best power adder out there for a smaller displacement engine is going turbo hands down, you can make within reason any powerband you want.
 

Ken04

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So, if you want to "feel" like you have a fast car, get the roots. If you don't mind feeling slower than you really are, the centri is a very cheap entry into the world of forced induction.

Ultimately, there are NO bad blowers for our cars. Just different good alternatives. All of which can be tuned and pullied to make more power than the stock bottom end can handle anyway.

racing aint street driving. Racing we're trying to keep the engine up in the mid/top of the hp/tq range, spinning wheels at the line, etc. Street cars are normally romped on at a lower rpm, which is where we'd feel the torque from a displacement blower.

If I was to buy a blower, it'd be a centri. I drive my car on the street more like when I race it. It's not a DD so I don't care if I 'feel' a huge torque surge from 1500 rpm.

Truth, no bad blowers.
 

rydon572

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Just ordered the M90, what would be a good price for the install? I can't do it myself I have major back problems. How much total, per hour, and how long for a shop install. I live in the KC, MO area if anyone knows anyone around here.
 

Boozshey

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Do it yourself if you can recruit the help of some buddies to do the lifting.
 

Swarzkopf

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I know the M90 is and was put on different applications, but meant for a V6 I think not.

It's most commonly associated with V6s- as someone else mentioned, Thunderbird Supercoupes and GM 3.8L's (GTP, Regal GS) both came with M90's from the factory and had quite a large following back in the day.

It looks like the M90 works great on our 3V, and maybe "meant" isn't the right word, but it has a long history with V6s (particularly 3.8Ls) and not much history with V8s.
 

808muscle

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Just ordered the M90, what would be a good price for the install? I can't do it myself I have major back problems. How much total, per hour, and how long for a shop install. I live in the KC, MO area if anyone knows anyone around here.

Its straightforward install not difficult like headers. A pro shop will prolly charge 10 hours or about $1000. You can't get your buddies to help you?
 

dagamore

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I know of two people over here in Germany with the M90 on 4.6L 3v, and both run fine, good quick cars, if you are looking for just a bit more power and or the SC whine the m90 will deliver, and often for quite a bit less then the larger SC.
 

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