Harrop twin screw sc for s65

[Longboarder]

^ ^ ^ that HP/TQ curve looks awesome for an AWD Audi ! That thing must launch off the line like a rocket. And is just a beast at all points in the RPM range...don't even need to downshift to get going.

[Verify]

Originally Posted by saxonb

Are you sure that you're interpreting these results correctly Sicke?

If you look closely at the graphs below, you will see three lines.

1. Baseline: Stock Audi RS4 B7 4.2
2. Middle line: TVS 1320 Audi RS4 B7 4.2
3. Top line: TVS 1740 Audi RS4 B7 4.2

You will note:

The 1740 kit (3) delivers a minimum increase in torque of 150 lb/ft and a maximum of 250 lb/ft over stock (1).

The 1740 kit (3) also delivers a minimum increase of 40 horsepower and maximum of over 200 horsepower over stock (1).

What exactly is a "STG 3" package, what is changed from stock?
Cant debate points without more information, but what i will say, is look at the giant dip in TQ past 5k rpm. Earlier TQ would be nice, but thats a huge loss.That a PD s/c cant flow well up top for the rpm the cars have

[saxonb]

Originally Posted by SickeM3

What exactly is a "STG 3" package, what is changed from stock?
Cant debate points without more information, but what i will say, is look at the giant dip in TQ past 5k rpm. Earlier TQ would be nice, but thats a huge loss.That a PD s/c cant flow well up top for the rpm the cars have

Well, let's use the data points at hand:

120ft/lbs over stock at redline is not a "loss". That is patently a "gain".

The TVS1740 kit employs the same SC as the Harrop E92 M3 kit, and same integrated intercooler design.

[Verify]

Originally Posted by saxonb

Well, let's use the data points at hand:

120ft/lbs over stock at redline is not a "loss". That is patently a "gain".

The TVS1740 kit employs the same SC as the Harrop E92 M3 kit, and same integrated intercooler design.

Doesn't go well then, because current data shows a loss of 100 ft/lbs from 5k-8k rpm on that, saying that the PD supercharger cannot meet high rpm requirements.

Does it say how much boost the STG3 is using? If its over 9 psi, its also not a good argument considering OEM strength of the S65.

As I said before, i prefer not to talk about a completely different motor arguing for the actual supercharger because it doesnt translate well for the S65. Thats unfair to those of you still expecting big things from it.

[saxonb]

Originally Posted by SickeM3

Doesn't go well then, because current data shows a loss of 100 ft/lbs from 5k-8k rpm on that, saying that the PD supercharger cannot meet high rpm requirements.

Does it say how much boost the STG3 is using? If its over 9 psi, its also not a good argument considering OEM strength of the S65.

As I said before, i prefer not to talk about a completely different motor arguing for the actual supercharger because it doesnt translate well for the S65. Thats unfair to those of you still expecting big things from it.

Here's another audi 4.2 positive displacement kit with no loss of torque compared to stock:




I also read that the audi 4.2 is:

1. over square bore and stroke: 84.5 by 92.8 millimetres
2. compression ratio: 12.5

I understand that this impacts the mechanical efficiency of the engine and indeed creates different torque characteristics to the over square and lower compression s65.

[Verify]

Im not arguing a loss of Tq compared to stock, that would be ridiculous. Im talking about over the benefits of mating the centri s/c to a high revving motor.

Now bringing in a completely different built motor into the equation couldn't be further from an articulate debate

[pbonsalb]

If I was building a motor, I'd consider twin turbos. Audi does a pretty nice job with its 4.0L twin turbo in the RS models.

[kiln]

Stage 1 details

[SECOND2NONE]

Hopefully a stage 2 comes out soon after

[saxonb]

Originally Posted by SickeM3

Im not arguing a loss of Tq compared to stock, that would be ridiculous. Im talking about over the benefits of mating the centri s/c to a high revving motor.

Now bringing in a completely different built motor into the equation couldn't be further from an articulate debate

All engines have torque degradation due to mechanical efficiency falling off at higher piston velocities.

The substantial torque degradation you speak off is a characteristic of the audi 4.2 not positive displacement superchargers.

[saxonb]

Originally Posted by kiln

Stage 1 details

That's awesome.

500hp at the wheels and 400 ft lbs peak torque at 4000rpm.

Can't wait.

[e46m3to135i]

Originally Posted by saxonb

That's awesome.

500hp at the wheels and 400 ft lbs peak torque at 4000rpm.

Can't wait.

Ummm that's not at the wheels. If you reads the info at the bottom of the ad is says" Dynapack axle data WITHOUT powertrain correction"

15% drivetrain correction would be about 425rwhp and 340 rwtq at 4K RPM.

-Nick

[regular guy]

Originally Posted by e46m3to135i

Ummm that's not at the wheels. If you reads the info at the bottom of the ad is says" Dynapack axle data WITHOUT powertrain correction"

15% drivetrain correction would be about 425rwhp and 340 rwtq at 4K RPM.

-Nick

I think you might have misunderstood what the post above says.

I've got a lot of experience with Dynapack and know them and Dynojets extremely well. I've even run 5-6 same cars on Dynapacks and Dynojets just to see how the dyno's compared.

For the most part, Dynapack and Dynojet give nearly identical results. In my tests, we had the results within 2-5 whp of each other. For crankshaft correction, I typically use 12% drivetrain loss for Dynapack. So just going by the numbers posted above, the translation from whp to chp would be: 500whp = 568chp, and 400wtq = 455ctq.

[MilehighM3]

Originally Posted by e46m3to135i

Ummm that's not at the wheels. If you reads the info at the bottom of the ad is says" Dynapack axle data WITHOUT powertrain correction"

15% drivetrain correction would be about 425rwhp and 340 rwtq at 4K RPM.

-Nick

Without correction means whp, not the other way around. With would add to the numbers, correct?

[Verify]

Without powertrain correction means its CHP not rwhp. Ie they did not correct for losses.

They could save themselves the trouble by at least posting the graphs.

[e46m3to135i]

Ok. I did a bit of researching between Kilowatt, Newton Meter and the numbers Harrop posted in the Stage 1 ad.

Seems Harrop did post the numbers in RWHP instead of crank as I was suspecting. Here's how I determined this:

- 3000 RPM delivers 460nm which equals 339rwtq. Harrop states 330nm stock, which is 243 rwtq. Most M3 put down round 250rwtq so this adds up

- 5000 RPM delivers 540nm which equals 398rwtq. Harrop states 340nm stock, which is 250 rwtq. Once again, the stock nm stated reflects what a M3 puts down in rwtq.

- 7000 RPM delivers 373kw which equals 500rwhp. Harrop states 255nm stock, which is 341 rwhp. The stock kw stated reflects what a M3 puts down in rwhp.

Convert those numbers to crank hp and you'll have:

3000 RPM- 400 Crank TQ
5000 RPM- 440 Crank TQ
7000 RPM- 614 Crank HP

What I don't understand. Is why they stated in the ad that the powertrain correction hadn't been corrected. I guess what they meant by saying that is that they haven't included the CHP numbers.

Either way like another guy said, a dynograph would have cleared up the confusion.

After finally confirming the numbers. This kit looks pretty damn good. If they come out with a Stage 2 kit by the end of this year or early next year, that will be the kit I jump on.

-Nick

[regular guy]

Originally Posted by e46m3to135i

Ok. I did a bit of researching between Kilowatt, Newton Meter and the numbers Harrop posted in the Stage 1 ad.

Seems Harrop did post the numbers in RWHP instead of crank as I was suspecting. Here's how I determined this:

- 3000 RPM delivers 460nm which equals 339rwtq. Harrop states 330nm stock, which is 243 rwtq. Most M3 put down round 250rwtq so this adds up

- 5000 RPM delivers 540nm which equals 398rwtq. Harrop states 340nm stock, which is 250 rwtq. Once again, the stock nm stated reflects what a M3 puts down in rwtq.

- 7000 RPM delivers 373kw which equals 500rwhp. Harrop states 255nm stock, which is 341 rwhp. The stock kw stated reflects what a M3 puts down in rwhp.

Convert those numbers to crank hp and you'll have:

3000 RPM- 400 Crank TQ
5000 RPM- 440 Crank TQ
7000 RPM- 614 Crank HP

What I don't understand. Is why they stated in the ad that the powertrain correction hadn't been corrected. I guess what they meant by saying that is that they haven't included the CHP numbers.

Either way like another guy said, a dynograph would have cleared up the confusion.

After finally confirming the numbers. This kit looks pretty damn good. If they come out with a Stage 2 kit by the end of this year or early next year, that will be the kit I jump on.

-Nick

It doesn't need to be this complicated. The Dynapack doesn't have CHP correction, so all Dynapack results will be WHP. The standard CHP correction for Dynapack will be 12%. Many marketing numbers will use 18%correction because frankly they look bigger than 12%. The best correlation you will find comes from www.rototest.com, which is essentially the same dyno as a Dynapack. Their results are just about 12% off CHP numbers with STD correction, and 15% off CHP numbers with SAE correction. Often times marketing numbers are reported in STD correction instead of SAE because STD is about 3% higher than SAE.

So let's see if I can reverse all of this and get closer to the real numbers.

3000 RPM: 460nm = 339wtq, 194whp = 145kW
5000 RPM: 540nm = 398wtq, 379whp = 283kW
7000 RPM: 509nm = 375wtq, 500whp = 373kW

Next let's convert STD correction to SAE correction with a 3% scalar:
3000 RPM: 447nm = 329wtq, 188whp = 141kW
5000 RPM: 524nm = 386wtq, 368whp = 275kW
7000 RPM: 494nm = 364wtq, 485whp = 362kW

Last let's convert STD correction to Crank TQ and HP using 12% correction factor:
3000 RPM: 523nm = 386ctq, 220chp = 164kW
5000 RPM: 614nm = 453ctq, 431chp = 321kW
7000 RPM: 578nm = 426ctq, 568chp = 424kW

I hope this helps.

[e46m3to135i]

Originally Posted by regular guy

It doesn't need to be this complicated. The Dynapack doesn't have CHP correction, so all Dynapack results will be WHP. The standard CHP correction for Dynapack will be 12%. Many marketing numbers will use 18%correction because frankly they look bigger than 12%. The best correlation you will find comes from www.rototest.com, which is essentially the same dyno as a Dynapack. Their results are just about 12% off CHP numbers with STD correction, and 15% off CHP numbers with SAE correction. Often times marketing numbers are reported in STD correction instead of SAE because STD is about 3% higher than SAE.

So let's see if I can reverse all of this and get closer to the real numbers.

3000 RPM: 460nm = 339wtq, 194whp = 145kW
5000 RPM: 540nm = 398wtq, 379whp = 283kW
7000 RPM: 509nm = 375wtq, 500whp = 373kW

Next let's convert STD correction to SAE correction with a 3% scalar:
3000 RPM: 447nm = 329wtq, 188whp = 141kW
5000 RPM: 524nm = 386wtq, 368whp = 275kW
7000 RPM: 494nm = 364wtq, 485whp = 362kW

Last let's convert STD correction to Crank TQ and HP using 12% correction factor:
3000 RPM: 523nm = 386ctq, 220chp = 164kW
5000 RPM: 614nm = 453ctq, 431chp = 321kW
7000 RPM: 578nm = 426ctq, 568chp = 424kW

I hope this helps.

Spot on!

[Verify]

Originally Posted by regular guy

It doesn't need to be this complicated. The Dynapack doesn't have CHP correction, so all Dynapack results will be WHP. The standard CHP correction for Dynapack will be 12%. Many marketing numbers will use 18%correction because frankly they look bigger than 12%. The best correlation you will find comes from www.rototest.com, which is essentially the same dyno as a Dynapack. Their results are just about 12% off CHP numbers with STD correction, and 15% off CHP numbers with SAE correction. Often times marketing numbers are reported in STD correction instead of SAE because STD is about 3% higher than SAE.

So let's see if I can reverse all of this and get closer to the real numbers.

3000 RPM: 460nm = 339wtq, 194whp = 145kW
5000 RPM: 540nm = 398wtq, 379whp = 283kW
7000 RPM: 509nm = 375wtq, 500whp = 373kW

Next let's convert STD correction to SAE correction with a 3% scalar:
3000 RPM: 447nm = 329wtq, 188whp = 141kW
5000 RPM: 524nm = 386wtq, 368whp = 275kW
7000 RPM: 494nm = 364wtq, 485whp = 362kW

Last let's convert STD correction to Crank TQ and HP using 12% correction factor:
3000 RPM: 523nm = 386ctq, 220chp = 164kW
5000 RPM: 614nm = 453ctq, 431chp = 321kW
7000 RPM: 578nm = 426ctq, 568chp = 424kW

I hope this helps.

Im confused now. How are you converting with no atmospheric data?

[regular guy]

Originally Posted by SickeM3

Im confused now. How are you converting with no atmospheric data?

You are technically correct that converting from STD to SAE will require atmospheric data -- which I do not have. But from experience, I know the difference will be between 2% - 3%, so I chose 3% just to approximate. The error will only be a few wtq/whp, so it should be close enough to give a ball park idea of what SAE correction would be like.

Converting to CHP doesn't require any atmospheric data because you're only factoring drivetrain loss.

[Verify]

Originally Posted by regular guy

You are technically correct that converting from STD to SAE will require atmospheric data -- which I do not have. But from experience, I know the difference will be between 2% - 3%, so I chose 3% just to approximate. The error will only be a few wtq/whp, so it should be close enough to give a ball park idea of what SAE correction would be like.

Converting to CHP doesn't require any atmospheric data because you're only factoring drivetrain loss.

If you don't know the conditions of CHP figures it really doesn't help either.

Maybe we should just pester them to get the graph up. I have a suspicion they didn't do that, because of higher RPM power, as 8000 rpm figures are not listed as well..

[regular guy]

Originally Posted by SickeM3

If you don't know the conditions of CHP figures it really doesn't help either.

Maybe we should just pester them to get the graph up. I have a suspicion they didn't do that, because of higher RPM power, as 8000 rpm figures are not listed as well..

Yes, I realize nobody asked for STD to SAE correction. But even my approximation will be within ~2-4 whp of accuracy. I'm sure to many that will be very helpful since SAE correction is the industry standard.