Comparing Turbocharge boost to Belt driven Supercharger boost, It appears that a specific Manifold pressure, let us say 12 PSI with a Belt drive supercharger would net MORE airflow through a reasonably free flowing exhaust than a Turbocharger set up at 12 PSI manifold pressure, due to the NET boost of a Turbocharger would have to take into account exhaust manifold PRE-Turbine back pressure .
Airflow through engine should be proportionate to the DIFFERENCE between Intake manifold pressure and Exhaust manifold backpressure.
Is this the case ?
To make equivalent horsepower from a given engine build, does one need substantially MORE BOOST from a Turbo charger than from a Belt drive supercharger ?

 

I’m a green as hell rookie on this but don’t forget the drag the supercharger puts on the engine and the power needed to spin it. In very generic terms, it may take 50hp to spin up a turbo to 12psi but it might take the supercharger 60hp to spin to 12psi (these are random numbers and have no scientific backing as I’m just speaking out loud here). Turbos have always been more efficient than superchargers as they are taking waste energy and converting it to something. In my experience, a turbo makes more power psi to psi than a supercharger.

 

All this depends on supercharger type and size. Same goes with a turbo. The compressor wheel size and shape (inducer/exducer) as well as the turbine size and shape (inducer/exducer). All that compared to the engine size and such.

Also something I noticed over the years, every supercharged engine I've taken apart had noticeable more wear on the front main bearing compared to N/A and turbo engines.

LIke mentioned, a supercharger takes power to make power.
a turbo uses engine "waste" to drive the turbine. So getting the drive pressure to a reasonable ratio compared to intake pressure will make a slight difference in power.

With all that being said. I like turbos

 

But turbos are pains in the *******

 

It's more about flow than pressure. Turbo's, when properly sized- are the better boost maker for peak power. Twin screws are hard to beat for torque. Prochargers are good for high RPM power (and keeping your 4L60 alive)

Think of the problem as if you're trying to fill a 5gal bucket with your garden hose. You can put your thumb over the hose, and increase the "pressure" immensely. Shoot water across the yard. This is "high boost, low flow" and it will take a long time to fill the bucket. Or, you can just let the hose flow "low boost, high flow" and the bucket will fill faster. The time it takes to fill the bucket is metaphor for creating horsepower

Boost as a measure of manifold pressure is simply an indication of the restriction the engine has. That is what is allowing the pressure to accumulate in the manifold and creating what you see on the gauge as "boost". Less restriction means less "boost" but more power is being produced

 

haha.
I've never had a issue in playing with turbo trucks and cars over the last 19-20 years. Besides broken 4l60s and that kinda fun stuff.

 

assuming both compressors are sized appropriately, the turbo setup will not only make higher HP - it'll also make much more average power because it produces torque a lot sooner than a centrifugal & is the more efficient compressor style due to the drive system differences described above. don't forget: horsepower is a mere calculation of how much torque is produced at a specific RPM. since the two flow about the same on the top end, you'd expect them to produce the same peak number (meaning the one using less power nets a better result).

i might have to use this hose pipe example later... some Jap-trap turbo tuner's been arguing with me for weeks on corvetteforum saying somebody's better off running higher procharger boost through the stock top end than doing a head/cam swap because he believes increasing engine VE a little will drop the centrifugal out of its map & consequently run hotter & make less power. he then continually backs all these claims up with doctoral dissertations on adiabatic efficiency for 20-30psi turbo maps

 

I need to avoid CF more than I do. My mental health would be happier for it

Lots of ijidts on there

 

it is entertaining, though

 

This wouldn't be a 'kingtalon' character would it...