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Discussion Starter · #1 · (Edited)
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Interesting @Rubber Duck need your analysis
I think it is absolutely the right way to go.

Since simple blowers such as our TVS Roots Blower
have problems filling the cylinder to 100%, then they
can't work in compressible flow as can turbo's or twin
screw superchargers.

To make big HP with a simple roots blower, one needs
to build a big engine, having a big valve, so one can run
a big runner and make big power.

With a turbo or twin screw, one can use a small engine,
valve size need not be as large, nor does the runner size.

The above simply relates to the fact that those compressors
can work in compressible flow, whereby the simple blower
cannot.

However, on the street with a heavy car, I still enjoy
my CTSV, as the simple DD / PD Blower provides
for immediate mass flow, which in turn provides for
immediate torque. :)

---------------------------------------------------------------


I posted the following info on this forum sometime back
regarding compressible flow and the value of 0.528.

But since we have so many new members I thought
I would post it once more.

----------------------------

0.528 What is Choked?
The parameter that becomes “choked” or
“limited” is the velocity of the air. It is more
accurate to use the term “choked velocity”
rather than “choked flow” when the absolute
pressure ratio of air through an orifice reaches
the value of 0.528.

In gas flow through an orifice there is an occasion
where the gas velocity reaches sonic
conditions.

This occurs for air flow when the
absolute pressure ratio is 0.528, or when the
downstream absolute pressure (P2) is 52.8%
of the upstream absolute pressure (P1).

Sonic velocity occurs for air flow when
P2 / P1 equals the value of 0.528.


For example, when P2 is 14.7 psia and P1 is 27.84
psia,
sonic velocity occurs through the orifice.

As P1 further increases there is no further
increase in the velocity of the air flowing
through the orifice.
***Here the compressor must be able to work in
compressible flow, or be able to 'Compress'
the air molecules into smaller size.

The above then serves to increase the 'Density' of the air.

In my opinion 'Velocity Choke' occurs at ~330 fps.
The Mach Number then would be. . . .0.59.

The above is not achievable in our engines, so
as I have indicated before; the issue with our
engines is that the simple roots blower won't
provide for a cylinder fill of more than 100%.


At that point, the pressure within the intake tract
tends to 'Bleed Back' through the case to blower
vane clearance, back into the intake manifold.

The above associates one with the first order problem.

Second order problem is that this air has been
preheated now and tends to cause 3rd and 4th
order issues, such as self detonation, tune
issues, etc.

Cheers
 

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I'm good with a simple blower, 900 wheel HP and 600+ foot-lbs at like 2000 RPM.

#driveslikestock

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I'm good with a simple blower, 900 wheel HP and 600+ foot-lbs at like 2000 RPM.

#driveslikestock

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Well yeah if you have E85 it’s a little easier, looks like the stang does. On pump 93!I’m sure I would only be slightly impressed too.


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Well yeah if you have E85 it’s a little easier, looks like the stang does. On pump 93!I’m sure I would only be slightly impressed too.


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To be fair, I'm only like 850 rwhp on 93 and minimal pulley. I will pulley up eventually.

Mustang was on a hub dyno, so subtract 10% for realistic numbers?

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Discussion Starter · #7 · (Edited)
To be fair, I'm only like 850 rwhp on 93 and minimal pulley. I will pulley up eventually.

Mustang was on a hub dyno, so subtract 10% for realistic numbers?

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Shit! I’ll be ecstatic if my car make 850whp on 93! Was the GT500 in that video on 93? I just assumed it was on E85. I guess I’m just impressed that much power was able to extracted without even opening the motor.
 

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The coyote motors do very well with more efficient heads and dual cams.

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Discussion Starter · #9 ·

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Shit! I’ll be ecstatic if my car make 850whp on 93! Was The GT500 on 93 in that video? I just assumed it was on E85. I guess I’m just impressed that much power was able to extracted without even opening the motor.
Yeah in the comments said it was some special E-something. Sounded canned like you have to order it like oil barrels? I always watch the big names posting up “..just had this Lt4 (or whatever) put down some serious power..on E” here in the northeast there’s virtually no E and so I’m not as impressed unless it’s a car running 93, then that could be me!


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some guys do buy e85 in drums, usually guaranteed 85% ethanol and nice and dry ( no water )

and some guys buy E98
 

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Yeah but a plaid is nearly as fast, takes zero skill set to build, tune or drive. Plus you can’t sit in the backseat of a mustang and have it drive for you.

Not to mention as bland and dated the plaid styling is……it’s straight


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Discussion Starter · #14 ·
Yeah but a plaid is nearly as fast, takes zero skill set to build, tune or drive. Plus you can’t sit in the backseat of a mustang and have it drive for you.

Not to mention as bland and dated the plaid styling is……it’s straight


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You forgot to mention that you can make the Plaid sound like any other car on the road too! :D
 
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