Sweet, I wasn't aware of this. I meant for general purpose consumer motorsport usage like the GT/GTX lineup.

I've seen these in the Fords and they have had a few teething issues with the dual compressor wheel design, but I'm still pretty excited to have 67mm power in a 58mm package (or 88mm in a 76mm package)

 

Driven Fab offered to make one for me, so they are an option as well


In other news, the wheels are starting to turn on getting my **** together, hopefully this will be on the car today with charge piping being fabbed next week

Untitled by Alex Whitacre, on Flickr

 

Which EFRs have you tried? What's the setup?

 

Like any product, some will love it, some won't. Warranty issues aside, I think the consensus is the EFR line performs very well. Perrin has tested them extensively and seems impressed http://blog.perrinperformance.com/bo...test-and-tune/

 

The EFR does what it is supposed to do and that is have best on/off throttle response and time to torque from low engine speeds due to the low inertia turbine wheel.

All these dyno plots showing the EFR spooling quickly, that's a function of turbine A/R, not wheel inertia. Put a small A/R on any turbo and it'll change the spool up on a dyno.

Perrin does some weird testing sometimes... Like he compared the EFR 7163 in small A/R to the old GT3076R. Then GTX3076R which is a much larger on the compressor side. He should have compared the 7163 to the GTX3071R as those are the closest two in compressor wheel (both 71mm) and turbine wheel sizes (63mm vs GT30 60mm). And he should have tested the GTX3576R, not the 3076, because it has been proven time and again the 3576 spools nearly identically to the 3076 but makes a lot more power.

In summary, don't buy an EFR if you are looking for peak power numbers because other turbos will make more power wheel size for wheel size; buy it for best on/off throttle response. I've seen compressor and turbine maps for the EFRs (except for the 7163 which I suspect the unique 'mixed flow' (which is really not all that mixed but mostly just an angled inducer blade, but marketing ya know?) has better efficiency than the standard EFR turbine wheel and their efficiency are lower than competition which is why you will not see the same peak power wheel size for wheel size.

Again, EFRs will excel in street driving where you want that on/off transient response benefit from the low inertia TiAl turbine wheel.

 

Mrfred

6758, 7670, 8374, 9174, 9180



spdracerut, you're correct, the AR and wheel geometry plays a big role, my biggest problem is that nobody is posting real data. I wanted to try the EFR series myself first hand and get real data because it seems that nobody else on the market is willing to. I have plenty of datalogs and can show what the transient response is between shifts to show exactly what time to torque is. What I want to see is people stop posting these dank spool memes and start posting real data so we can really see if these EFRs are anything more than a marketing exercise backed up by deep deep vendor discounts to push a product.


To everyone else:
Seriously? Has Perrin posted a datalog showing boost recovery? No. Have they shown what their ramp rate is to show they aren't screwing with the load rate of the car? No. Have they shown road pulls for an apples to apples comparison? No.
Have any of these other companies that try and sell you stuff been able to show you an actual chart or graph of this "amazing transient response?" Nope. They just tell you "oh it feels amazing, it's not something that can be seen on a dyno chart". They aren't lying there, this has to be from a datalog from the ECU.

Stop trying to push this vendor marketing crap as gospel. I've literally just said that you can manipulate spool times by adjusting the ramp rate on the dyno and choosing what RPM they're pulling at. Even on the Perrin tests they are doing more than just swapping the turbo in some cases and have issues with their TGVs for example which throws out the whole test, not to mention it's on a dyno with no information on what the ramp rate is. They're trying to sell you something because Borg Warner gives them turbos to test, just like any other big name vendor.

So here's real data, not regurgitated marketing nonsense. I'm not trying to sell you anything. I don't give a damn what turbo you buy and I don't get free stuff from any vendor. Please don't fall into the trap of being a fanboy for a product for a company that literally could not care less about you.


Here's a 2-3-4 hit.



Time breakdown

First 100% throttle 6:50.629
Hitting boost target 6:51.876
Elapsed time: 1.246 seconds to reach boost target (18psi)

Application of throttle after the shift from 2nd
6:53.714
Reaching boost target in 3rd gear
6:54.162
Elapsed time to reach target (22psi): .447 seconds

Application of throttle after the shift from 3rd:
6:56.2586872
Reaching boost target in 4th gear
6:56.8883128
Elapsed time to reach target (26psi): .629 seconds

My impressions? It recovers boost pretty quick. Not amazing quick, but reasonably quick. Stay tuned for my follow up update on the 6870 gen2, which is supposed to be "laggy". For reference, this turbo on a dynapack with a usual ramp rate of 500rpm/sec (what most operators would run) makes boost target in 4th gear at 4900rpm with the pull started from 2000rpm.

 

So how about you post some side by side apples to apples data for us? The info you have posted so far is hard to understand and gives us nothing to compare it against. You say precision turbos are better but then don't show why.

 

I think his final sentences said he was going to post gen2 6870 data (after he installs it and presumably other new hot parts) for direct comparison. I'm pretty interested to see this.

 

Thanks for the info. Very interesting. What was the rpm at the moment the next gear was engaged?

 

What turbo are those graphs and time breakdown for? What rpm range does it hold boost through?

 

I don't say precision turbos are better at all anywhere in any text I have ever posted. As a matter of fact, they have a bad reputation of lasting for only 20000 miles, making amazing peak power and then falling apart and laying down smokescreens, just as the EFRs have a reputation of puking out turbine wheels.




You are correct, I will post new data but not hot parts have to be changed. The only addition (which I don't REALLY have to add) is a Turbosmart raceport BOV. Technically I could do the recirc valve and vent it back into the inlet, but it's not really necessary and I have a turbosmart bov lying around. I'm super curious as to what the data will show as well, because the marketing about the ti-al wheels certainly struck a cord with me thus the reason I've spent so much time and money testing them out. I'm also going to test a comp 6471 or 6671. This will be with a 94mm exducer compressor wheel as well.

The moment of shifting from 2nd to 3rd was at 8563rpm and re-engaged at 6041rpm. In 3rd going to 4th, 8463 re-engaging at 6476. I had 150rpm of "lug" in 2->3 and 100rpm in 3->4 (that little dip in RPM meaning the RPMs dipped down a hair faster than I caught the gear.

Keep in mind this is on a stock ap2 transmission. I already blew up 4th gear and am swapping in the spare. It does not like 500+ft lbs of torque. I'm looking into sourcing a quaife or g-force transmission for a replacement.

Edit:

Here's the log itself if you're interested in viewing it with AEMdata
https://drive.google.com/open?id=0B6...NyV3l0Y1VPenh3

You can download it here;
http://aemelectronics.com/files/soft...ta_4.01.01.exe

 

That sure looks like you are saying that Precision turbos are better (i.e., more power and better spool) than the comparable EFR. Any data to support that claim?

 

Lets go step by step shall we?

A 62mm turbo will spool faster than a 67mm turbo assuming using the same turbine material. Because Physics.

A 67mm EFR will struggle to make 900 on a Evo or Honda platform and will have to taper boost at high RPM operation to ensure you don't spit the turbine wheel out. At 35 PSI @ 8500rpm on a F22c1, I was at max turbine wheel speed for the 9174 and made 820hp. With more timing I might of been able to hit 850. Again, this is on Joe's Dynapack. Ramp rate of 500rpm/sec

A 62mm comp turbo on Joe @ LocashCNC's integra makes 940hp

A 62mm custom garret that Joe tested also made above 900hp.

A 62mm turbo with an inconel wheel probably spools the same or better as a larger 67mm EFR with a gamma-ti wheel. That's a big difference in size.

In summary, you can make EFR 67mm power with a 62mm of a competitor such as Precision or Comp. It remains to be seen what a 62mm will do on my s2000 to have like for like numbers. I am also going to be testing out a Comp 6271 (CT43X compressor cover with a .81 AR T4 housing) because I want real world numbers. I'm also super curious what the 6870 will do. There's a lot of hype about the turbo and it remains to be seen if it will live up to it. I am not going to be testing any Garrett turbos with factory compressor wheels because they're already known to not make good power per mm combined with the fact that the GT35 turbine wheel is garbage.



I have an honest, personal question for you. Why are you compelled to defend BW? Did they give you a free turbo? Do you have an EFR on your car and are emotionally invested in seeing the outcome of this to validate or invalidate your beliefs? A turbo is a turbo man. I don't give a damn who makes what, what I care about are numbers. If any other vendors want to chime in with hard data, back to back logs of an EFR with any other vendor's turbo, I'd love to see it. That's good stuff. What isn't good stuff is senseless fanboyism for a company that literally couldn't care less about any of us.

 

Why are you guys comparing "spool" on two different dyno's, let alone with one pull starting at 1500rpm and the other at 2500rpm. The comparison is not possible.

This is a silly way to categorize turbos. Judge them on spool or power goals or overall packaging, but why would it matter what power per mm they make? If there was a 70mm turbo that spooled faster than a 65mm turbo from another brand but made the same power, wouldn't you still pick the 70mm?

Seems to me you've decided that you don't like the EFR range and are willing to circumvent logic to give reasons why.
Please point out the 62mm turbo that's making 900whp? The 6466 doesn't even make 900whp unless it's on no-wastegate death mode.

Spool on the dyno is worthless in general. Logs on the racetrack or street are the only things worth looking at.

So you're judging boost recovery time off a setup that's handicapped by a need to shift softly? Doesn't seem like the best test conditions...

 

Uhhh, what? There are SOOOO many factors that go into this besides inducer size...

Blah blah, what do they trap? How do they spool? Dyno numbers only go so far in telling a turbos story.

If you're going to ask me the same question, I'll tell you this: I'm not even defending BW, I'm merely pointing out the holes in your logic. Sure, the BW line has it's faults, just like the rest of the turbos on the market, because EVERY turbo is a compromise. That doesn't mean the lineup is ****.