Harrop twin screw sc for s65

[Pro-AM3]

Originally Posted by Sered

That 5 years of experience didn't teach you much if you can't glance at a timeslip and see something is up. 1.8 60', 11.2 ET and 121mph traps. Normally a 1.8 60' will net you low 11s at mid 120mph. There's about 3-4mph missing there. I'd believe a 1.6 60', 11.2 ET and 121mph traps.


I know this from 15+ years of experience as a performance enthusiast and hanging around a lot of people who are into serious drag racing plus having a lot of my own cars on tracks of various sorts (along with engine builds and other things in my own garage). This is just basic 60' vs ET vs trap stuff.


Owning an M3 is just bragging rights too. Is it worth the money you spend when I could go spend less than half as much and make a 335i blow your doors off?

See what I did there? It's worth the money if it makes you happy. Period. In the end this is a hobby for 99% of people out there. I have a favorite saying about hobbies: "Spending money on a hobby is an investment in your sanity."

Again, your entitled to your own flawed opinion. You can see the evidence in the dynos they posted. I believe EAS dynos are usually 20-30hp higher than anywhere else. So to only make 500 on that is very very underwhelming. Now, look at the graphs of the harrop kit, after 5k rpms thet very very sketchy. You can see the power is inconsistent and lacks pull after pull it gets less powerful and less constant.

That translates into the real world, exactly in what we see with that 1/4 mile slip. good low end Umph, dying topend power. You think its just a coincidence that everything the performance world has known about the pro/cons of these types of FI producers just showed itself there?
I dont. Its almost as if it played out EXACTLY like we knew it would.

BTW, your math is way way off on the 1/4 mile predictions, as a i said. They dont play in the real world, as we have seen from the E9x chassis. Its all basic stuff. if you know the chassis and how it affects THIS car, with THIS powerband and THIS gearing.

Once again, that slip proved what we all knew about the differences in FI delivery. Plain and simple, cant argue with facts, cant argue with history. You can construe "what-ifs", but in the end it is what it is, and right now, its lacking some serious performance

BTW hobbies are hobbies, but if your trying to spend money to keep your SANITY, it wont go well to drop $15k and still be slower than a $5k 550 kit..

[BPMSport]

I know it's not the case with everyone here, but my M3 is set up to be a daily driver with occasional track use. Having the fastest quarter mile means nothing to me. A daily driver that's very fast, with gobs of torque on tap at any moment is what I was looking for. Slightly easing into the throttle and having ample passing power without having to downshift or ring the car to high RPM is why I choose this kit for my car. If I wanted to be the fastest in the quarter, I'd probably opt for a centri kit and perhaps do a low comp build. This kit shifts the torque up through nearly the entire rev range, which the centri kits can not do because boost is a factor of RPM.

[Sered]

Originally Posted by BossManE90

Again, your entitled to your own flawed opinion. You can see the evidence in the dynos they posted. I believe EAS dynos are usually 20-30hp higher than anywhere else. So to only make 500 on that is very very underwhelming. Now, look at the graphs of the harrop kit, after 5k rpms thet very very sketchy. You can see the power is inconsistent and lacks pull after pull it gets less powerful and less constant.

The graph I saw of the Harrop kit showed a typical PD blower torque band. They are strong down low and usually begin to die off a bit up top. Considering its only 5-5.5psi of boost, I think 470-500whp is just fine on a PD blower considering it has 1000 more rpms of usable powerband. Low-end power doesn't translate into good ETs or good traps; it's average power; and on a E9X, it's generally all power made above 5000rpms.

That translates into the real world, exactly in what we see with that 1/4 mile slip. good low end Umph, dying topend power. You think its just a coincidence that everything the performance world has known about the pro/cons of these types of FI producers just showed itself there?
I dont. Its almost as if it played out EXACTLY like we knew it would.

I think you need to step outside and see other platforms. Trap speeds are a combination of two things: average power/weight and rolling traction. Just facts. You cannot dispute this.

BTW, your math is way way off on the 1/4 mile predictions, as a i said. They dont play in the real world, as we have seen from the E9x chassis. Its all basic stuff. if you know the chassis and how it affects THIS car, with THIS powerband and THIS gearing.

No its not considering most other ESS kits I've seen that trap 121-122 (there are a lot of them) are generally running 11.7-11.8 with 1.8 60's. And considering the countless other platforms I've had hands on experience with, the times look like something is up. We'll see when we get more info but my bet is they let off early. You don't run a sub 1.8 60' and trap only 121mph while still nearly running a 10 second ET. I bet this is quicker than any low-boost S/C kit thus far.

And your 'THIS car, with THIS powerband' statement doesn't hold much water considering ALL blower M3 cars up to this point have been centri-based. THIS blower is a positive displacement blower and I'd bet money that a 470whp Harrop kit will make more average power than a 500whp Centri-kit on either a DCT or a 6MT (even more so on a 6MT).

BTW hobbies are hobbies, but if your trying to spend money to keep your SANITY, it wont go well to drop $15k and still be slower than a $5k 550 kit..

The Harrop kit is like $12k and a 550 kit is about $6500. You really don't like the facts do you? My point was that someone else can always go faster for cheaper but that doesn't mean your purchases (and by extension, your hobby) is invalidated. Good way to come off like a dick though. Good job.

My point is hobbies are supposed to be fun. Justifying your purchases based on someone else's standards isn't the point of it.

[pbonsalb]

The PD blower car will be faster most of the time in daily driving. Wring it out and the centri will be faster. At the strip, you are in the rpm range at which the PD car has an advantage for about 10% of the run -- the first second. But on the street you are probably in that rpm range 90% of the time.

If I had the money, it would be a tough choice for me. I'd like to see a stage 2 PD kit. What I would like most is a twin turbo. The Audi RS7 does pretty nicely right off the show room floor with a twin turbo 4L V8.

[Pro-AM3]

Originally Posted by Sered

The graph I saw of the Harrop kit showed a typical PD blower torque band. They are strong down low and usually begin to die off a bit up top. Considering its only 5-5.5psi of boost, I think 470-500whp is just fine on a PD blower considering it has 1000 more rpms of usable powerband. Low-end power doesn't translate into good ETs or good traps; it's average power; and on a E9X, it's generally all power made above 5000rpms.

Same peak HP as ESS 550 kit, yet slower mph, more low rpm power, yet slower MPH. See what im getting at, if it were a case of equal topend, then the more low end would make the car faster. It isnt.

I think you need to step outside and see other platforms. Trap speeds are a combination of two things: average power/weight and rolling traction. Just facts. You cannot dispute this.

Your right, cannot dispute this, re-read what I wrote above. its not making the power up top where you need to make power to be "faster" Its just facts, you cannot dispute this

No its not considering most other ESS kits I've seen that trap 121-122 (there are a lot of them) are generally running 11.7-11.8 with 1.8 60's. And considering the countless other platforms I've had hands on experience with, the times look like something is up. We'll see when we get more info but my bet is they let off early. You don't run a sub 1.8 60' and trap only 121mph while still nearly running a 10 second ET. I bet this is quicker than any low-boost S/C kit thus far.

1.7 60', this car had a 1.7 60', so a 1.8 60' of a ESS 550 kit making less TQ is not a fair comparison. Your countless experiences are failing you, because you will not accept that there are multiple ESS 550 kits that have run just as quick, and faster MPH. This is fact, you can not argue this.In fact, You could look at hotrod magazine this week, and see what they called "drag Week" and see 50+ cars do low 11s at 113-120mph. SO there goes your "experience" with drag racing.


And your 'THIS car, with THIS powerband' statement doesn't hold much water considering ALL blower M3 cars up to this point have been centri-based. THIS blower is a positive displacement blower and I'd bet money that a 470whp Harrop kit will make more average power than a 500whp Centri-kit on either a DCT or a 6MT (even more so on a 6MT).

Average power? So get a 7.5 psi kit on the database and lets see. Id bet it doesnt, because it cant make the same peak power battling the heat. Id also say that average power is only a part of the equation. the biggest gain in power for this kit, is below 3k rpms, thats only 1st gear, after that, centri is GONE!



The Harrop kit is like $12k and a 550 kit is about $6500. You really don't like the facts do you? My point was that someone else can always go faster for cheaper but that doesn't mean your purchases (and by extension, your hobby) is invalidated. Good way to come off like a dick though. Good job.

So, 1/2 the price for the same performance is a good deal? Arent you the guys that bought a used kit to try and modify it and now angry that its not performing the way you thought it would? there are hobbies, and then there are wastes of money.

My point is hobbies are supposed to be fun. Justifying your purchases based on someone else's standards isn't the point of it.

BOLD

But again, this is just my opinion based on the facts at hand
History and technology tel us these types of S/C's have issues at high RPM
History shows us the S65 is heat tempermental
Present results show us that these types of s/c's have heat issues at high rpm
present results show us that a gear swap and centri blower would give a user the same feel and better performance for less investment.

[regular guy]

Man, if I had time right now, I'd generate those area graphs you guys want from the Harrop vs. 500whp Centri kit. I'd even model the drag race in CarTest. But I'm leaving for NY/NJ tomorrow and won't be back for a week. If you guys are still arguing when I get back, I'll see if I can do it then.

[regular guy]

I found time to do it. Here's the area-under-curve graphs, and the CarTest estimates for ESS @ 511whp vs. Harrop TVS. The closest I had for ESS was 490 or 511. You guys wanted 500, so I shot over to 511 instead of down to 490. The CarTest results are using the actual WHP dyno charts input into CarTest for analysis.

[WayneM3]

Thank you for doing this - it really helps to see the advantage of the positive displacement blower. I know it isn't exactly a fair test but can you do the graph comparison for a "regular" ESS 625 kit? I am curious to see the performance comparison there. I would love to see the comparison with my Evolve kit but since I have no dyno files to offer right now I don't know how that could be done.

[pbonsalb]

What if we compared the power from a $10,999 ESS VT-2 650 centrifugal to the power from the $12,999 Harrop positive displacement blower and let the ESS spend the extra $2000 on an x-pipe?

[regular guy]

Originally Posted by WayneM3

Thank you for doing this - it really helps to see the advantage of the positive displacement blower. I know it isn't exactly a fair test but can you do the graph comparison for a "regular" ESS 625 kit? I am curious to see the performance comparison there. I would love to see the comparison with my Evolve kit but since I have no dyno files to offer right now I don't know how that could be done.

Here's the comparison with LM's Evolve car. I'm really up against a time wall getting the the airport, so I'll see if I can bang out the ESS 625 comparison as well.

[regular guy]

Here's the comparison with Drew's ESS 625 kit.

[BrewRifle]

6K RPM + = Rocket.

[kitw]

Originally Posted by regular guy

Here's the comparison with Drew's ESS 625 kit.

Thanks again for doing these... I wish the Harrop was cheaper, because the comparison between the VT1-550 kit and the Harrop makes me think Harrop all day... price ignored. :/ But, with the ESS VT2-625 kit coming in similarly priced, and making significantly more power 6000-8000rpm... it'd be hard to justify the Harrop kit without significant discounting involved.

That said, for a purely street car, I bet the Harrop feels faster in a lot of situations, unless you have the room to rev out. (I've owned a few cars that were faster than my e92 M3 - Z51 C7, tuned 997 turbo, tuned f80 and I always appreciated the large belt of midrange torque.)

[Ezio]

Originally Posted by kitw

Thanks again for doing these... I wish the Harrop was cheaper, because the comparison between the VT1-550 kit and the Harrop makes me think Harrop all day... price ignored. :/ But, with the ESS VT2-625 kit coming in similarly priced, and making significantly more power 6000-8000rpm... it'd be hard to justify the Harrop kit without significant discounting involved.

That said, for a purely street car, I bet the Harrop feels faster in a lot of situations, unless you have the room to rev out. (I've owned a few cars that were faster than my e92 M3 - Z51 C7, tuned 997 turbo, tuned f80 and I always appreciated the large belt of midrange torque.)

i think the torque feel is different on the harrop. but regardless the 625 kit is better value.

[81bear]

Originally Posted by BrewRifle

6K RPM + = Rocket.

QFT

[maloo]

Does the Harrop have a louder whine than the 625? Sound may be factor for some guys.

[81bear]

Originally Posted by kitw

Thanks again for doing these... I wish the Harrop was cheaper, because the comparison between the VT1-550 kit and the Harrop makes me think Harrop all day... price ignored. :/ But, with the ESS VT2-625 kit coming in similarly priced, and making significantly more power 6000-8000rpm... it'd be hard to justify the Harrop kit without significant discounting involved.

That said, for a purely street car, I bet the Harrop feels faster in a lot of situations, unless you have the room to rev out. (I've owned a few cars that were faster than my e92 M3 - Z51 C7, tuned 997 turbo, tuned f80 and I always appreciated the large belt of midrange torque.)

I can tell you I have trouble getting on the gas hard in 2nd, 3rd, and to a lesser extent 4th gear above 4500-5000 rpm so I can't image how difficult it would be with this harrop kit.

I am very familiar with the TVS kits as my old car (B8 S4) had one and it made great power down low and felt very linear with a tune that kept the bypass valve closed. It was an extremely fun car to drive around the street! It also showed well at the drag strip, knocking out a 11.7 @ 119mph, on race gas.

With that said however, I would figure it would get frustrating having so much torque down low and not having awd to get the power down... I find it frustrating modulating the throttle above 4500-5000 rpm to avoid going sideways I can only image how annoying it would be at 2500 rpm!

To me, the Harrop kit seems to better resemble the power band of the F80 M3/M4 and I've seen them struggle with traction issues, hopping curbs and such...

[81bear]

Originally Posted by maloo

Does the Harrop have a louder whine than the 625? Sound may be factor for some guys.

Without a doubt... I can't hear any whine to be honest. The only whine I hear is from the Derlin diff bushings. So if you'd like some whine but rather get the ess 625 kit, get the diff bushings as well..

[BobS]

Serious question - Doesn't the difference in dyno's play a huge role in those comparisons? Without base numbers, we are just going with peak numbers from different dyno's on different days, conditions, fuel, etc. Find a high reading dyno and you win. Doesn't seem accurate to me...even though I see the SAE corrections and temp/humidity is noted..

Also, I understand the area under the curve plays a role, but using the first comparison, the Harrop has 29 more peak wtq than the ESS car. I wouldn't call that "gobs of tq" lol.

I also question whether that tq makes sense in a car engineered to rev to 8400 rpms, with a engine designed to have a power band in the high rpms, gearing for that high rpm car, and a DCT engineered with shifts and gear ratio's for high rpms.

[regular guy]

Originally Posted by BobS

Serious question - Doesn't the difference in dyno's play a huge role in those comparisons? Without base numbers, we are just going with peak numbers from different dyno's on different days, conditions, fuel, etc. Find a high reading dyno and you win. Doesn't seem accurate to me...even though I see the SAE corrections and temp/humidity is noted..

Also, I understand the area under the curve plays a role, but using the first comparison, the Harrop has 29 more peak wtq than the ESS car. I wouldn't call that "gobs of tq" lol.

I also question whether that tq makes sense in a car engineered to rev to 8400 rpms, with a engine designed to have a power band in the high rpms, gearing for that high rpm car, and a DCT engineered with shifts and gear ratio's for high rpms.

You've bought into a bunch of propaganda about hi/lo reading dynos and different day, different results. These are SAE corrected dyno's, which normalizes the results weather conditions. A very detailed study was done on this and found it very accurate when operated within the parameters specified by the SAE J1349 horsepower correction specification. So for the most part, SAE correction works.

But these graphs aren't really meant for a horsepower comparison anyways. People wanted to see area under the curve. If it the correction was off by 0.5% does that even matter to this comparison? Take each one in opposite directions, and AUC 2011 becomes 2001, and AUC 1967 becomes 1976. Making the final comparison 2001 to 1976 instead of 2011 to 1967. Does that really matter? Not to me it doesn't.

BTW, and just to add more fuel to what I just said: the propaganda I'm referring to is what vendors say to their customers to explain lackluster results. I've proven this propaganda wrong many times already, and it's landed me in trouble because the vendors pay to complain and get their way. So show me a vendor who's said it, and I'll almost guarantee that I'll show you a vendor who is trying to sell a product with lackluster results.

[BobS]

Fair enough....

I will say though you can't deny there are some real heart breaker dyno's out there and also some that read real high, not to mention different kinds. Good comparison's though, its interesting to see the differences in tq/hp area under the curve.

With ESS pricing their 625 kit at $8995, its almost impossible to beat for the $$

[regular guy]

Originally Posted by BobS

Fair enough....

I will say though you can't deny there are some real heart breaker dyno's out there and also some that read real high, not to mention different kinds. Good comparison's though, its interesting to see the differences in tq/hp area under the curve.

With ESS pricing their 625 kit at $8995, its almost impossible to beat for the $$

The heartbreaker is by brand, not necessarily by model within the brand. Nobody should compare across brands, but comparing against correctly run dyno's within the same brand, even on different days and different weather conditions should be OK. Although there are ways to manipulate dyno's and intentionally depress a baseline just so you can make the finished results (the delta) look bigger. How many people you see talking about "the delta" too?

That's a general rule, but not always the case. On load bearing dyno's like Dynapack, the ramp rate and gear ratio plays a role. So you will see a lot of variance on Dynapack because people don't all follow the same procedure. Much, MUCH less so on a Dynojet.

Early in the S65 supercharger days, one vendor tried to explain his lackluster results by saying the Dynojet in his neighborhood "read" 80whp low compared to the Dynojet at Specialty-Z a few blocks away. So I took my 600whp car to both dyno's on the same day and the results were within 5whp of each other. You don't even want to know the shit storm that created. I suspect some people still aren't over that because I see some of them still going out of their way to attack everything I post. (Can't wait to see if they respond to this...then you'll know who they are. :-) )