Bullet Performance supercharger by Mercury Performance

[BRAWL]

Originally Posted by tjoy

http://www.sprintex.com.au/sprintex/superchargers/

can't tell what model they used from cross-referencing the pic w/ the product pages

Sprintex S5-210 is what they are using. Sounds awesome!

[WTF]

Car is presently at mercury motorsport, supercharger kit was made by Bullet (using a Sprintex SC). Car has a ECUTEK flash tune, which is yet to be tuned. The guys at Mercury will be tuning it prior to the car's departure for WTAC.

I will see if I can get some more pics tomorrow, however it was generally 'requested' that the official unveiling be at WTAC this coming week, so to respect their wishes, I was asked to hold onto the majority of the pics until later..

[civicdrivr]

Nice! Can't wait to see results.

I noticed that the hood is missing the insulation. Does it no longer fit?

[mechaghost]

Can't wait to see the dyno results

[serialk11r]

mmm not liking the twin screw compressor, the parasitic power loss is going to be quite high but props to them for getting it working!

[rusty959]

Originally Posted by serialk11r

mmm not liking the twin screw compressor, the parasitic power loss is going to be quite high but props to them for getting it working!

[Flat Black VW]

looking forward to this one....

[serialk11r]

Originally Posted by rusty959

:P Eaton TVS is superior IMO, higher efficiency, volumetric efficiency, low parasitic power consumption. Admittedly they're hard to find.

Just look at the Sprintex page, at 1.4 bar discharge pressure (close to max efficiency point) the power consumption is something like 7-8kW at 7000rpm. At 0.94L displacement, and 0.4 bar boost pressure, that corresponds to about 5000rpm engine speed. Recall that at 60mph the engine is already turning 2600rpm. The supercharger is turning about 3700rpm. Admittedly the manifold pressure will be very low at cruise, but the majority of the power consumed by the rotary twin screw compressor is through internal compression, and so the power consumption you'll see at cruising speeds is not going to be that far below the 1.4 bar discharge power consumption.

It's a bit hard to see since the resolution of those charts sucks, but you can see that the power consumption at 3-4k rpm supercharger speed is in the neighborhood of ~2-3kW or about 4hp going down the drain. When the supercharger is not working against positive manifold pressure this is admittedly lower, but it will be on the same order of magnitude. It only takes something on the order of 15hp average to roll down the highway at 60mph, and you can definitely expect the supercharger to be consuming at least 2hp extra.

Eaton TVS superchargers will drain perhaps half a horsepower or less by comparison, under the same conditions, and give you boost at similar levels of efficiency, probably better in fact.

[Tomzilla]

Originally Posted by serialk11r

:P Eaton TVS is superior IMO, higher efficiency, volumetric efficiency, low parasitic power consumption. Admittedly they're hard to find.

Just look at the Sprintex page, at 1.4 bar discharge pressure (close to max efficiency point) the power consumption is something like 7-8kW at 7000rpm. At 0.94L displacement, and 0.4 bar boost pressure, that corresponds to about 5000rpm engine speed. Recall that at 60mph the engine is already turning 2600rpm. The supercharger is turning about 3700rpm. Admittedly the manifold pressure will be very low at cruise, but the majority of the power consumed by the rotary twin screw compressor is through internal compression, and so the power consumption you'll see at cruising speeds is not going to be that far below the 1.4 bar discharge power consumption.

It's a bit hard to see since the resolution of those charts sucks, but you can see that the power consumption at 3-4k rpm supercharger speed is in the neighborhood of ~2-3kW or about 4hp going down the drain. When the supercharger is not working against positive manifold pressure this is admittedly lower, but it will be on the same order of magnitude. It only takes something on the order of 15hp average to roll down the highway at 60mph, and you can definitely expect the supercharger to be consuming at least 2hp extra.

Eaton TVS superchargers will drain perhaps half a horsepower or less by comparison, under the same conditions, and give you boost at similar levels of efficiency, probably better in fact.

TL;DR

Go with Eaton if they produce and release an SC for our cars.

[Dimman]

Originally Posted by serialk11r

:P Eaton TVS is superior IMO, higher efficiency, volumetric efficiency, low parasitic power consumption. Admittedly they're hard to find.

Just look at the Sprintex page, at 1.4 bar discharge pressure (close to max efficiency point) the power consumption is something like 7-8kW at 7000rpm. At 0.94L displacement, and 0.4 bar boost pressure, that corresponds to about 5000rpm engine speed. Recall that at 60mph the engine is already turning 2600rpm. The supercharger is turning about 3700rpm. Admittedly the manifold pressure will be very low at cruise, but the majority of the power consumed by the rotary twin screw compressor is through internal compression, and so the power consumption you'll see at cruising speeds is not going to be that far below the 1.4 bar discharge power consumption.

It's a bit hard to see since the resolution of those charts sucks, but you can see that the power consumption at 3-4k rpm supercharger speed is in the neighborhood of ~2-3kW or about 4hp going down the drain. When the supercharger is not working against positive manifold pressure this is admittedly lower, but it will be on the same order of magnitude. It only takes something on the order of 15hp average to roll down the highway at 60mph, and you can definitely expect the supercharger to be consuming at least 2hp extra.

Eaton TVS superchargers will drain perhaps half a horsepower or less by comparison, under the same conditions, and give you boost at similar levels of efficiency, probably better in fact.

Didn't we figure out that Lysholm maps are complete and include hp to spin and Eaton maps need more math and stuff?

[serialk11r]

Originally Posted by Dimman

Didn't we figure out that Lysholm maps are complete and include hp to spin and Eaton maps need more math and stuff?

Yea, but Eaton's powerpoint presentation on downsizing and downspeeding has a map that describes the no load power requirements. It takes nothing to spin a bypassed Eaton compared to your typical twin screw, the lowest marked line was 0.5kW and the cruising load point fell far below that line, so much that they didn't even bother to figure out how much power it was consuming, they just said "below 500W". Just eyeballing it, it looks to be probably 200W or less. Lemme dig up the chart.

Anyhow, I doubt mechanical efficiency is that big of a deal. The centrifugal supercharger folk claim well over 90% mechanical drive efficiency.

EDIT: Okay nevermind maybe not 200, this looks kinda like 300W to me, but still, the twin screw rotary compressor is consuming probably 5-10 times that.
http://www.engine-expo.com/forum_200...rt_walling.pdf
page 19
The example used is a 2.0L engine with 0.9L compressor, so very comparable.

[GirlyScions]

Originally Posted by serialk11r

:P Eaton TVS is superior IMO, higher efficiency, volumetric efficiency, low parasitic power consumption. Admittedly they're hard to find.

Just look at the Sprintex page, at 1.4 bar discharge pressure (close to max efficiency point) the power consumption is something like 7-8kW at 7000rpm. At 0.94L displacement, and 0.4 bar boost pressure, that corresponds to about 5000rpm engine speed. Recall that at 60mph the engine is already turning 2600rpm. The supercharger is turning about 3700rpm. Admittedly the manifold pressure will be very low at cruise, but the majority of the power consumed by the rotary twin screw compressor is through internal compression, and so the power consumption you'll see at cruising speeds is not going to be that far below the 1.4 bar discharge power consumption.

It's a bit hard to see since the resolution of those charts sucks, but you can see that the power consumption at 3-4k rpm supercharger speed is in the neighborhood of ~2-3kW or about 4hp going down the drain. When the supercharger is not working against positive manifold pressure this is admittedly lower, but it will be on the same order of magnitude. It only takes something on the order of 15hp average to roll down the highway at 60mph, and you can definitely expect the supercharger to be consuming at least 2hp extra.

Eaton TVS superchargers will drain perhaps half a horsepower or less by comparison, under the same conditions, and give you boost at similar levels of efficiency, probably better in fact.

Maybe we will see better displacement charges someday but if its only 4 hp loss im still excited to see it finished.

[serialk11r]

Originally Posted by GirlyScions

Maybe we will see better displacement charges someday but if its only 4 hp loss im still excited to see it finished.

4hp loss at cruising is like losing 20% fuel economy

Like I said in reality it might be more like 2 or 3hp, but again that's losing 10-20% fuel economy.

[rusty959]

Even with a 20% fuel economy drop the car will still get good mileage by my standards.
No matter what, I am excited to see what they can do because every new piece like this is just further driving the aftermarket. Plus a roots type just looks/sounds sexy.
Ill probably still go turblo though.