Harrop twin screw sc for s65

[regular guy]

Here's the dyno chart for the rest of the world.

514 whp, 390 wtq.

[regular guy]

Originally Posted by leigh

This car has a stock x-pipe, akra rear muffler, 98RON, 6MT and I think it's even a stock air filter.

I think this is an old dyno and they have done a little more tuning and the numbers are a little better but I'm not 100% on that

Boost level?

[OM VT3]

Originally Posted by regular guy

Boost level?

5.5psi

[regular guy]

Here's the Dyno Database entries:

Semi-Stock: http://www.s65dynos.com/showDyno.php?recID=687
Harrop TVS: http://www.s65dynos.com/showDyno.php?recID=688

[Meff]

Originally Posted by regular guy

Here's the Dyno Database entries:

Semi-Stock: http://www.s65dynos.com/showDyno.php?recID=687
Harrop TVS: http://www.s65dynos.com/showDyno.php?recID=688

you are a good human

[kitw]

Originally Posted by SECOND2NONE

Only thing that concerns me is boost control. Hoping there are some fail safes.

wait, boost control on a belt driven supercharger? It's called pulley sizing

[OM VT3]

Originally Posted by kitw

wait, boost control on a belt driven supercharger? It's called pulley sizing

Lol no it has an electronic valve to control boost

[regular guy]

And since I know this is inevitable, I might as well beat everybody to it. This was the closest entry I could find in the Dyno Database to compare.

Harrop TVS vs. ESS VT2-575.

[Someone?]

Nice!^ gobs more Tq everywhere, and a much better HP curve then Centri blower.

[regular guy]

And I know this is inevitable too. Comparing equal torque. Like the one above that tried to compare equal WHP, this was the closest I could find in the Dyno Database. It's not perfect, it doesn't start until 3000 RPMs. The next closest I could find was more than 10wtq higher; so I kept this one for the comparison.

Harrop TVS vs. ESS VT2-625

[regular guy]

Let me explain something about these comparisons. They are Dynapack vs. Dynojet. They are also Dynapack SAE-Adapted vs. SAE-J1349 corrections. So it's not intended to be an apples to apples comparison. These comparisons are meant to compare HP and TQ curves, not results.

There's only one Dynapack supercharged entry in the Dyno Database for an ESS kit where I can actually export the data and make an apples to apples comparison. The next graph I post will be by that method, Dynapack vs. Dynapack, and SAE-Adapted vs. SAE-Adapted.

[regular guy]

Here's my final graph.

This graph is generated from Dynapack vs. Dynapack, SAE-Adapted vs. SAE-Adapted. This graph compares the Harrop TVS vs. ESS VT2-625. If I had other ESS (or other Centrifugal) superchargers in the Dyno Database using Dynapack, then I would have been happy to compare those. But there just isn't anything else to compare on the same type dyno with same correction factors.

I've also added the Harrop dyno files spreadsheet to the Dyno Database. This is the spreadsheet containing all of the data, and used to compare against the other results. Feel free to download the spreadsheet and other files from the database and make your own comparisons.

Harrop TVS vs. ESS VT2-625 on Dynapack using same correction factors

[OM VT3]

Originally Posted by regular guy

Here's my final graph.

This graph is generated from Dynapack vs. Dynapack, SAE-Adapted vs. SAE-Adapted. This graph compares the Harrop TVS vs. ESS VT2-625. If I had other ESS (or other Centrifugal) superchargers in the Dyno Database using Dynapack, then I would have been happy to compare those. But there just isn't anything else to compare on the same type dyno with same correction factors.

I've also added the Harrop dyno files spreadsheet to the Dyno Database. This is the spreadsheet containing all of the data, and used to compare against the other results. Feel free to download the spreadsheet and other files from the database and make your own comparisons.

Harrop TVS vs. ESS VT2-625 on Dynapack using same correction factors

Harrop have one of a ess 650 on there dyno there's still beats it still 6500rpm

[regular guy]

Originally Posted by leigh

Harrop have one of a ess 650 on there dyno there's still beats it still 6500rpm

See if you can get them to send me the Dynapack run files from the Harrop and ESS kit. PM/EMail me if that sounds possible.

[OM VT3]

Originally Posted by regular guy

See if you can get them to send me the Dynapack run files from the Harrop and ESS kit. PM/EMail me if that sounds possible.

I'll speak to them

[BPMSport]

I think using an unreleased, unofficial dyno chart for comparison is premature to say the least.

[kitw]

Originally Posted by leigh

Lol no it has an electronic valve to control boost

Is it bleeding off boost at the top end, Audi style and is unnecessarily spinning the blower? this seems like a stupid design.

I doubt they would do that, although with the wide rpm of the s65, maybe, to produce more low end? Thermodynamics of the justification make my brain hurt

[Soorena]

Originally Posted by kitw

Is it bleeding off boost at the top end, Audi style and is unnecessarily spinning the blower? this seems like a stupid design.

I doubt they would do that, although with the wide rpm of the s65, maybe, to produce more low end? Thermodynamics of the justification make my brain hurt

It only "bleeds" boost when you go off throttle.
With a single or twin throttle bodies, a positive displacement application is like this: Throttle body(s)=> Supercharger=> Intake ports
In our cars with ITBs it's like this: Supercharger=> Velocity stacks => Intake ports

The wastegate-like valvetronic system in Harrop's design (similar to Audi's) is what that enables us to run a positive supercharger, it releases boost off throttle. Otherwise we would blow the manifold or velocity stacks.

[BobS]

Looks very promising! I guess this is their "base kit"? The hp/tq curves are very nice.

[saxonb]

Originally Posted by kitw

Is it bleeding off boost at the top end, Audi style and is unnecessarily spinning the blower? this seems like a stupid design.

I doubt they would do that, although with the wide rpm of the s65, maybe, to produce more low end? Thermodynamics of the justification make my brain hurt

My understanding is that there is a blow off valve operating in the Harrop kit:

One throttle = closed
Off throttle = open

[Hujan]

Originally Posted by regular guy

Here's my final graph.

This graph is generated from Dynapack vs. Dynapack, SAE-Adapted vs. SAE-Adapted. This graph compares the Harrop TVS vs. ESS VT2-625. If I had other ESS (or other Centrifugal) superchargers in the Dyno Database using Dynapack, then I would have been happy to compare those. But there just isn't anything else to compare on the same type dyno with same correction factors.

I've also added the Harrop dyno files spreadsheet to the Dyno Database. This is the spreadsheet containing all of the data, and used to compare against the other results. Feel free to download the spreadsheet and other files from the database and make your own comparisons.

Harrop TVS vs. ESS VT2-625 on Dynapack using same correction factors

625 kit making 660 whp? Hmmmm.

[Jonjt]

Originally Posted by Hujan

625 kit making 660 whp? Hmmmm.

+1

I do believe the VT2 graphs are of crank hp, whereas the Harrop graphs are of wheel HP. I think the VT2 650 kit makes around 570whp, peak.