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Old 01-21-2020, 05:38 PM   #26
subydude
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Quote:
Originally Posted by stealthlead View Post
That's true... Cumulatively it would save me $900 in piping and wastegates. I have also heard very good things about EFR's IWG once the actuator is used. Isn't it quite a bit easier to control boost with an EWG? Damnit you're making me reconsider an IWG now.... It would make sense as I hate the noise of external hence rerouting back into DP
IWG is just as easy as EWG to control. The difference is 4 port actuators were available for EWG long before IWG. This get's into a lot of variables, but the simplified version is you can do pretty much whatever you want with an IWG on an EFR and going EWG does not really net you a big gain given the associated cost.

IWG get a bad reputation because on little turbos they're small and restrict flow causing boost creep, or they blow open too early causing boost to taper down. If you have a well thought out and sized IWG setup (like the EFR's have) then it works pretty much the same as an EWG. In the end EWG is better, but you have to be pushing a lot more than a street car would to really reap the benefits.
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Old 01-21-2020, 08:30 PM   #27
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We already discussed this, you're going 9180

but seriously, 7163 is awesome for a street car. You rode in mine and it wasn't super laggy and pretty good for a street car.
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Old 01-22-2020, 10:03 PM   #28
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We already discussed this, you're going 9180

but seriously, 7163 is awesome for a street car. You rode in mine and it wasn't super laggy and pretty good for a street car.
9180 and send it to the moon.

It was a great turbo, I can't deny that. I'm still torn between the two.

On a related subject, in the theatretical situation I go with an EWG 7670, should the EWG's be 38mm or 44mm?
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Old 01-22-2020, 10:55 PM   #29
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Originally Posted by stealthlead View Post
9180 and send it to the moon.

It was a great turbo, I can't deny that. I'm still torn between the two.

On a related subject, in the theatretical situation I go with an EWG 7670, should the EWG's be 38mm or 44mm?
That depends on how much boost you want to run.
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Old 01-23-2020, 07:47 PM   #30
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I think the problem between the 7163 and the 7064 is the turbine opening. they are different, the 7163 is a t25 and the 7670 is a t3 so you cant really swap between the 2 of them.
Probably late to the party on this but he said TS, so they're both T4.

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Originally Posted by subydude View Post
I'd take a 7163 for something fun on the street. Low 400's on pump gas and higher 400's on E85. The 7670 wouldn't hit full boost until after 4K but would give another 50ish hp to both numbers. If I were tracking it'd be a toss up but anything below track stuff and the 7163 is hard to beat.
I think the 7163 is an awesome street turbo. With that being said, if you want a more rev happy power band, I'd go with 7670. Won't have the same low end kick in the pants but as stated, responsive 400+ on pump is great.

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Thanks for the reply! I doubt the aluminum chra makes a huge difference anyways. Do you think it's a good idea to be seeking a twinscroll setup?
The aluminum housing, in my opion, is really only for the weight conscience people. If you're at the point that you're fighting for a few lbs here and there, by all means, it isn't that much more. I think my aluminum 7163 was ~10.3 lbs. Talking sub 5 kg turbo. Aluminum CHRAs also are mandatory water cooling.

The titanium CHRA TR30 turbos we ran on the DP cars were the only, comparably sized, turbos that I've known to be lighter. I think they were ~8lbs each IIRC....but also like $10k a piece
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Old 01-25-2020, 12:42 AM   #31
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Hi stealthlead

I have been thinking along a similar line: I want a fun street car. I have a GR WRX that I ice race it and sometimes autocross. If I am going to be plunking down a bunch of cash and spending a bunch of time I want to know the ins and outs of why one setup is better than another. There are decent information out there to inform your decision.


I think the only drawback to a twin scroll setup is the cost. If you are willing to be patient full race manifolds have turned up on the nasioc every great while. Also...if you are patient, you can save your pennies and do it right and do it once as you mentioned. That said, the information is out there for you to look through to inform your decision. There are two places that I have come to use extensively and I will list below.

First is the BW website. Read their EFR catalog and then their "technical training book", a wealth of info written well and backed up with sound engineering. Particularly interesting is the discussion of how/why they developed the turbine housings and wastgates. Their matchbot is kind of amazing.

Here is the link to the EFR catalog: http://www.turbos.bwauto.com/tools/d...&r=1920&d=2169
Here is the link to the EFR Technical Training Book: http://www.turbos.bwauto.com/tools/d...nt&r=759&d=901
Here is the link to the matchbot: http://www.turbos.bwauto.com/aftermarket/matchbot.aspx

Matchbot is a great calculation tool that can help you put quantitative results behind why one turbo is different than another (only BW turbos though). You can use it to understand how turbine choice affects the spool and what you can expect. You can use it to build a fairly detailed power/torque curve. It only allows 6 data points, but you can use it two or three times to fully map the engine range say six points between 2000-4000 rpm and six between 4000-6000 rpm. With that in mind here is a comparison of a 7163 with the .8 a/rr turbine housing to the 7670 with the .85 a/rr turbine housing

7163: http://www.turbos.borgwarner.com/go/OOG7WB
7670: http://www.turbos.borgwarner.com/go/EW7DEK

Second, look at the Cobb Dyno Database. There is a wealth of information there. You can easily do a search for a particular turbo and find some relevant cars, take those data and plot them in excel or just do a few comparisons within the webtool. It can be very educational. You can get a sense for what things look like. Look at enough of these curves and you can get a sense of the trades made for high horsepower numbers.

Here is the Cobb dyno database link: https://dyno.cobbtuning.com/dyno/

As to the original question, I keep coming back to the 7163 with the twin scroll turbine housing. It seems like it would be great fun for a street and short course car. I think for the 7160 the loss at lower engine speed is not worth the bigger top end. Here it is on E85: http://www.turbos.borgwarner.com/go/E34GIW

cheers
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Old 02-01-2020, 07:24 PM   #32
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Quote:
Originally Posted by Homemade WRX View Post
Probably late to the party on this but he said TS, so they're both T4.


I think the 7163 is an awesome street turbo. With that being said, if you want a more rev happy power band, I'd go with 7670. Won't have the same low end kick in the pants but as stated, responsive 400+ on pump is great.
Damn good to see you still here Micah,

If you have a minute and stumble upon this reply, shoot me a PM. I would love to catch up bro !!

Hope you are well !!
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Old 02-04-2020, 03:56 PM   #33
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For anyone wondering I ended up going with an externally gated g25 660
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Old 02-04-2020, 06:43 PM   #34
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I'd love to know how much power you end up with, and at what RPM you get full boost with that turbo.
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Old 02-04-2020, 11:10 PM   #35
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Damn good to see you still here Micah,

If you have a minute and stumble upon this reply, shoot me a PM. I would love to catch up bro !!

Hope you are well !!
One better, just texted you...or your old number

...we'll see
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Old 02-05-2020, 07:25 PM   #36
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Don't bother with a G series. The EFRs blow them out of the water. Garret's turbos are very outdated comparatively.

The newer EFR wastegates can flow 40% of the exhaust gasses out of the internal wastegate. No reason to use an EWG unless you're trying to make stupid power. Similarly, the integrated CHRA should be more than sufficient. You won't have an obnoxiously loud sneeze when you shift (hate that myself), and not using an external recirculation valve reduces the amount of stuff in your engine bay (less things = less things that can break).

Aluminum CHRA/turbine housing is a bad idea if you have high EGTs or want to use anti-lag. The housing can distort under high thrust load when it's hot, and after that it's time for a new turbo. I personally stay away from them unless the build is for a limited/restricted series, then it's just weight savings and the turbo is getting thrown out anyways.

Also, the EFRs have the Gamma-Ti (TiAl, titanium aluminide) turbine wheels. They're light as a feather, strong, and don't fatigue from heat cycling nearly as much as many other alloys.
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Old 02-06-2020, 04:57 PM   #37
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^^^seems very opinion based.

I think the EFR and G-series have their pros. From the motorsports side of things, I have firsthand and many secondhand experiences of the EFR turbine wheels not living up to race conditions for long. Then I have the same of Mar-M lasting very well. However the transient response of the EFR turbos is wildly fast. So pros and cons. Comes down to what you're needing in your application.


With this being said, I still own four EFR turbos. Haven't played with the G-series myself.
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Old 02-06-2020, 05:20 PM   #38
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Quote:
Originally Posted by NSFW View Post
I'd love to know how much power you end up with, and at what RPM you get full boost with that turbo.
I'd also be interested in these stats.
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Old 02-06-2020, 05:23 PM   #39
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I love my 7163.

A local here put a g25-660 on his car and it put down 498/444 on a mustang dyno at 27 psi. Spool seemed no different than my 7163.

For reference, I put down 461/461 on a Dynomite dyno at 29 psi, but was falling to 25 cause my WG couldn't keep up. (Another story)

but as Homemade pointed out...the EFRs shine with transient response.
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Old 02-08-2020, 10:24 AM   #40
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I know there'll always be disagreement between bw and garrett's (and keep in mind I thought about this decision hard for two years), all I can say is I rode in two BW's and one g-series. I was instantly sold on the g. The spool was unreal and I instantly understood what some of you have mentioned how the BW's boost onset is more predictable and the garretts hit more like a freight train. The decision became really simple when I looked at the dyno chart comparing my vf48 with the g25-660 - it spooled up 200rpm later making 474hp vs my tiny 310 hp. Keep in mind it was turned down about 150hp as the build it was on had a 5 speed trans. Its also worth noting these turbo's are TINY. They save a lot of room and for me having the ability to run it at 400 with great spool and turn it up down the line was worth it. I went ewg just because I've seen so many people have issues with iwg @ altitude here.. just seemed easier. Will hopefully post up dyno sheets in the foreseeable future...
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Old 02-10-2020, 10:53 AM   #41
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Here is a Borg SX257 T3 .63 AR with Pump + Meth at 3600ft above sea level.

Basically its a journal bearing 7670. So yes it will have great street manners.

https://i.imgur.com/mTp94O2l.jpg
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Old 02-27-2020, 06:58 PM   #42
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I mean it's a beefy turbo but I dont think it is that bad just controlling the boost
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Old 11-23-2020, 10:12 PM   #43
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I am pondering the same question for my E85 build (a station opened near my house recently! ). I am leaning towards the Full Race TS IWG EFR kit, but it's hard to find results with the 7076, or G25-660 or G30-660/770. The EFR7163 seems to be the most popular.

I'm trying to get an idea of how much the 7076 shifts the boost threshold vs the 7163. It seems like the 7076 should make ~40hp more.

I spent a bunch of time playing with matchbot but I don't really know what I'm doing. It seems like the 7670 can start making more boost than the 7163 starting at around 3250rpm. It's estimating 100ft lbs more at 3250 with the 7670. But I'm a noob and don't know what I'm doing, so I imagine that this isn't realistic. I imagine it's especially unlikely to get to these values in 2nd gear, but I don't really know. Are there parts of the compressor chart or turbine map that are more achievable in lower gears, or should I just ignore that?

7163: http://www.turbos.borgwarner.com/go/K4M3HL
7670: http://www.turbos.borgwarner.com/go/OEUQV1

I'm guessing that differences in spool between the two turbos are just down to the different rotational moments of the different wheels. I think it's operating on a scalar function, so it would be pretty easy to estimate if that data is available. Does anyone know it if it is, and if so what it is? Or am I incorrect?

Anyone have a good idea of this?

Thanks!
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Old 11-24-2020, 03:52 AM   #44
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in my opinion I think the efr 7163 turbine housing is just too small for ej25. think the 7076 would be a better match if you are looking top end ultimate power on an efr. it shouldnt spool that much lower but you have the much bigger hotside which will flow way better than the turbine housings on the efr7163.
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Old 12-17-2020, 12:38 PM   #45
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Originally Posted by subaru_gc8 View Post
in my opinion I think the efr 7163 turbine housing is just too small for ej25. think the 7076 would be a better match if you are looking top end ultimate power on an efr. it shouldnt spool that much lower but you have the much bigger hotside which will flow way better than the turbine housings on the efr7163.
+ 1 for bigger hotside, imo 7670 even to small for ej25. Get your self pressure sensor in header and watch back pressure.
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Old 12-17-2020, 01:00 PM   #46
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And I'm over here on the small hot side 6758 and tell people it's just fine to make 425 whp and 475 wtq. 7163's are 500+ whp. If you're going off back pressure, yeah there's optimal, but spool is really going to suffer, especially for a street turbo. Until you move the turbo somewhere into the same zip code as the exhaust ports running a smaller exhaust housing will increase spool a good bit. It's only when you have the added heat energy of running close to the exhaust ports can you get basically the same spool as a small hot side with the high exhaust velocity of high rpm too.
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Old 12-23-2020, 07:50 PM   #47
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Quote:
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For anyone wondering I ended up going with an externally gated g25 660
How did that preform for you? These look great for street applications.
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