Twin turbo vs Supercharging LS motors? What's the vibe nowadays?

[IJ.]

years ago, we dynoed my then vortech blown 5.7 vy ute. just running the belt on the blower cost over 40rwhp on a dyno run.

i.e ran the car with no boost without blower belt on and then with.

if the belt is still spinning the ****ing pulley it's taking power.

This was the point I was trying to make earlier, NOTHING is "Free Spinning" the overall ratio is something like 7.4:1 so it's going to take power to turn, as I posted earlier I'd be impressed by Magnusson's claim of 1/3hp/100 Kmh as an old school 6/71 took about 100hp to turn at 5000 rpm!

[JezzaB]

This was the point I was trying to make earlier, NOTHING is "Free Spinning" the overall ratio is something like 7.4:1 so it's going to take power to turn, as I posted earlier I'd be impressed by Magnusson's claim of 1/3hp/100 Kmh as an old school 6/71 took about 100hp to turn at 5000 rpm!

1/3 of a hp?? What's it disengage the gears from the transmission and just run the pulley on the bearing??

[feistl]

Just because there is a valve dont mean the blower isnt making heat and costing power. The engine is still driving the blower at full tilt but the benfits are being blown out the back door. So the PD blower with a valve will have a heavy cost of power but not making any power. Also its just recirculating engine heat if not on boost. If its a top mount blower it has to be heatsoaked as the heat from the engine rises straight into it. If its a twin screw blower then its always generating heat whether its valve is open or not as its internally compressing air. The eaton type by design generates so much heat when its on boost and when not on boost it recirculating engine heat.

The centifugal by design isnt costing much power as its not spinning hard down low and it free spins. Doesnt exchange heat with the motor, only up in rpm is it costing power to make power. The PD system is heavily taxing the motor of power but for most of the driving its being vented out the back door?

Correct me if im wrong here, but the eaton twin screw pd charger (EG HTV1900 or HTV2300) only has partial compression between the lobes, the compression actually occurs in the manifold itself. So when the value is open, the charger is only making a small amount of boost and only using a small amount of power to be driven. You seem to be implying that its using FULL power while making no boost pressure? If thats what your saying, then your technically incorrect.

There is some air which is recirculated and yes it will suffer some heat soak, but the amount is still relatively low. In that video with the heat soak comparison they shown a 22hp drop (On 450hp) when heat soaked... Thats a ~5% drop in power when heat soaked....

Considering most HTV2300 setups are making 400rwkw or more, dropping a few hp here or there doesnt really seem that big a deal? Or maybe thats just me...

[IJ.]

1/3 of a hp?? What's it disengage the gears from the transmission and just run the pulley on the bearing??

It's powered by Unicorns

Correct me if im wrong here, but the eaton twin screw pd charger (EG HTV1900 or HTV2300) only has partial compression between the lobes, the compression actually occurs in the manifold itself. So when the value is open, the charger is only making a small amount of boost and only using a small amount of power to be driven. You seem to be implying that its using FULL power while making no boost pressure? If thats what your saying, then your technically incorrect.

There is some air which is recirculated and yes it will suffer some heat soak, but the amount is still relatively low. In that video with the heat soak comparison they shown a 22hp drop (On 450hp) when heat soaked... Thats a ~5% drop in power when heat soaked....

Considering most HTV2300 setups are making 400rwkw or more, dropping a few hp here or there doesnt really seem that big a deal? Or maybe thats just me...

Agreed even the best calibrated Butt Dyno would have trouble picking that drop in the real world...

Also looked like they were rolling into the throttle so the Dyno Graph Traces would be comparable....

[1HDT 05]

I think most of the discussion is out of context. On the street both applications are great I wouldn't say no to either if they rolled up on my door step. At the drags the same thing, they are even in their negatives and positives. At gymkhana they are both good. Here's the controversial part, they both suck at a true racetrack, because both of them fail with heat issues. Before you say nay etc etc I have been on GTR forums, 350 and 370z forums and M3 forums and all the forced induction setups have heat issues at the racetrack. Unless of course they are dedicated racecars. You want to track your car? Then steer clear of forced induction, period. If you want to be a dyno queen or straightline (boring) drag specialist, then either will suit. For on road my turbo under 3k is a dream to drive, over 3k all hell breaks loose. And for street thats the way I reckon you want it, pussy at low revs, monster after.

[vessloveit]

Do you not agree?

Not agreeing or disagreeing I just like to know if information given on any internet site is good or not, as we all know there is a lot of misinformation on the net.

[Solone]

Not agreeing or disagreeing I just like to know if information given on any internet site is good or not, as we all know there is a lot of misinformation on the net.

Research those points. . Pretty sure you will come to same conclusions