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Old 01-22-2018, 04:11 PM   #26
subydude
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Quote:
Originally Posted by Scargod View Post
Yes! That's very interesting. During a tune would that be something you should/could see or verify in any other way than a drop in power? Boost held pretty steady till the near-end and Matchbot doesn't seem to indicate that I should have needed more boost to have flat torque
Wouldn't it be noticeable to the tuner that more boost didn't affect power? I mean he did go up .4 PSI and it lost four HP over those 300 RPM's.
Good catch I think!
The BPV would have no affect on boost pressure in the manifold. It's at the compressor housing and you're measuring boost pressure well beyond that. So even if the BPV was leaking 10 psi, the turbo would still be making that .4 increase in the manifold beyond it. You would see a drop in pressure on your gauge if it was leaking that much.

The issue most people have with the BPV is it's set soft and can open at part throttle which results in a whistling sound. Running a stiffer spring cures that. There's actually a little note about it on some sites around.
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Old 01-22-2018, 04:16 PM   #27
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Only other comment is I'm aware of other people using TS 7670's making the torque you're talking about (mid-450's for wtq) over a long RPM range. I could see the tuner taking into account a non modified deck block and keeping the timing artificially low which would account for the drop off up top along with the lower torque. You've got a lot of nice parts and (I'll be the first to say it) a moderately oversized turbo for your goals. However, playing tag on track with fast guys....yeah, that tune is definitely on the "will last forever" side of things.
Thanks, I guess. Longevity and "enough power" was my goal. Talking to the tuner about this on Monday did not provide many answers. He did not dial it back intentionally at the end.

WHich begs the question: I have a badder one in the works, but it is not closed-deck either. Can I safely get to 500 WHP with it?

Last edited by Scargod; 01-22-2018 at 04:18 PM. Reason: Adding comment
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Old 01-22-2018, 04:34 PM   #28
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The BPV would have no affect on boost pressure in the manifold. It's at the compressor housing and you're measuring boost pressure well beyond that. So even if the BPV was leaking 10 psi, the turbo would still be making that .4 increase in the manifold beyond it. You would see a drop in pressure on your gauge if it was leaking that much.

The issue most people have with the BPV is it's set soft and can open at part throttle which results in a whistling sound. Running a stiffer spring cures that. There's actually a little note about it on some sites around.
I don't get that first comment. As I recall the BPV is measuring on the output side of the compressor. Couldn't it get to where it could not hold the boost (not be responsive and stay closed enough)?
I do have the stronger spring.
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Old 01-22-2018, 05:00 PM   #29
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Thanks, I guess. Longevity and "enough power" was my goal. Talking to the tuner about this on Monday did not provide many answers. He did not dial it back intentionally at the end.

WHich begs the question: I have a badder one in the works, but it is not closed-deck either. Can I safely get to 500 WHP with it?
I laughed at your italics. I'm not being mean, just commenting logically If you're running less than 12-13 degrees of timing at peak torque and below 16-17 at high RPM, then it's dialed back for E85, especially at those boost levels.

The closed deck thing is kind of hard to determine. The stock semi-closed deck can last at higher power, but as power increases so does cylinder pressure. Eventually you'll have an issue there and it's hard to give it a hard power level since things are variable. I'd swag it and say much past 500 whp on a reasonable dyno and you're on borrowed time. It could last forever, or you could have a bad one and it could fail early.

Closing the deck is a bandaid as it helps support the cylinder and reduces movement. Generally they seem to add a few hundred whp of reliability, but they'll still fail at higher hp. Sleeving is arguably better than closing the deck, but more costly and more prone to issues.

Personally, sub 600 whp, I think a closed deck is nice. Yes, it's technically a bandaid, but often times bandaids are all that's needed for us privateers.

I have an 05 STi I bought for cheap that I'm going to leave semi-closed even though it may eventually see 400+ whp. If I decide to go past 450ish I'd likely pull it out and close the deck.

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I don't get that first comment. As I recall the BPV is measuring on the output side of the compressor. Couldn't it get to where it could not hold the boost (not be responsive and stay closed enough)?
I do have the stronger spring.
The BPV is on the output of the compressor, but you're measurement of boost is after the BPV. If the measurement doesn't waver and you can increase boost (and have it measurably increase) then a leak at the BPV has zero effect on the system. If you saw a loss of boost pressure after the BPV, then it would point to a leak there. No loss, no leak.
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Old 01-22-2018, 05:40 PM   #30
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I missed the boost curve in the plot the first time around there and assumed it was dropping off with torque and not holding all the way to redline.

We don't know if he has to crank up wastegate duty to get it to stay there, although you'd think the tuner would figure out a leak if that was the case.
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Old 01-22-2018, 05:51 PM   #31
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Other than I probably need to try cranking up the WG actuator pressure have we come to any consensus at all?
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Old 01-22-2018, 06:04 PM   #32
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Other than I probably need to try cranking up the WG actuator pressure have we come to any consensus at all?
You likely have a very conservative tune. The parts aren't a restriction at this power level. I'd try increasing boost by multiple PSI at the top end instead of .4 psi.
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Old 01-22-2018, 06:41 PM   #33
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Are you talking about the 2.5i manifold, or something else? I haven't done too much research on those, but the general consensus seems to be they're better for power than the stock STi red manifold.
Yes, the 2.5i manifold. It is going to move your powerband 500-800rpm to the left compared to an sti manifold at higher power levels. If you want to make power from 3000-6000 then it will create earlier spool, more mid range torque/hp but make higher rpm power more difficult. All engine parts have a power "curve" of efficiency, this part is a lower curve than the sti one. As an example on an sti with peak hp at 8300rpm switching to the 2.5i manifold created about 500rpm earlier spool however it also required a lot more boost and timing to even match peak hp as it would fall before 8000rpm. the owner removed it straight after for a custom manifold. It also reduced throttle response. It would be ok for an autox car but not a track car which spends more time at high rpm

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First off, thanks to everyone for their advice. I'll try and answer latest relevant questions/concerns.
First, given that the majority of comments focus on the exhaust, I still wonder how it has such a dramatic downturn in power?
If the downpipe or turbo-back is choking it then why is it no less dramatic at lower boost/power?
If the wastegate is being blown open all of a sudden then that might be a credible argument. Whether it's 23.0 PSI or 20.6, it still falls off at about the same rate and same RPM spot.
Preload on the WG actuator canister was to spec: 3mm (3 nut turns)
I used the Borg Warner BCSV (boost control solenoid valve) that came with the turbo (no other ECBS used),
and YES, it is internally wastegated, as in stock wastegate.

I don't want to kill the messenger, and I am somewhat of a neophyte in this area, but the BW EFR line of turbos is for racing and high-performance applications. Unless there is something defective I don't see why it shouldn't perform satisfactorily in this application. As mentioned, it's just beginning to work at the point where it drops off. There's lots of wastegate action on the low and high end. Matchbot says it's 38% at 6,800-7,200.
I chose twin scroll and the smaller turbine so I could get a better low RPM response. I don't understand how that could be causing what's happening (in such a dramatic fashion).
EFR turbos have good turbine tech and not as great compressor. As the compressor is more important for high rpm power on a subaru that is why Garrett tend to be better at power production at high rpm and higher pressure ratios. they perform better on some engines than others and there are a lot of variables involved, I have seen great results on some cars and horrible results on others. They are not ideal on a Subaru except at lower pressure ratios and for mid-range powerbands. Your setup with an oversized turbo might allow for higher rpm power however normally they will not ramp boost safely and you will definitely need to ramp it up to make peak power in the 8000rpm range. I'm afraid you may have asked your tuner for low rpm response which technically isn't needed for the track. You really just need power from 4500-8000 and your current 350wtq would make a nice safe 500whp.

The reason exhaust with an internal wg is a concern is that you need 3" for your power level, but you also need a 1.5" wg dump as well because you are dumping all of that extra unused exhaust into your turbine housing/dp and could be choking it. This means you can run less timing and be less safe, especially on longer pulls and high rpm. You can mitigate this using a 4" dp, can still go to 3" after the b-pillar, just use a long merge.

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Originally Posted by Scargod View Post

Intake: Mine is port matched and smoothed. Everything is "blueprinted". A NA can equal most good intakes and outflow my flow-benched big valve heads. They are also pretty-well balanced on the runners.
From thread on intakes:
Modified EJ25 SOHC Big Plenum Long Runner
Runner 1 314 CFM
Runner 2 303 CFM
Runner 3 308 CFM
Runner 4 314 CFM
Average 309.75 CFM
Runner to runner max variation 11 CFM or 3.5%

Was there something left on the table? For sure, because I am a play racer and this stuff's expensive. I am already faster than 95% of the cars at a track day/HPDE event. I don't want 500 WHP.
Those numbers don't really mean much because they were not connected to an engine. All they mean are not a physical restriction, but do not tell you where in the rev range with your compression, your cams that it will have its efficiency. As I posted above, we have found it to have a lower rpm efficiency than the stock sti piece. that may be different with a different engine build.

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Originally Posted by subydude View Post
Regarding intakes, I have a 2.5i manifold on my shelf waiting to go on this year. I don't think that's a restriction either. In fact, I don't think the stock STi manifold would be a major restriction at these power levels.
It isn't a restriction per se, it just makes power at lower rpm by moving the powerband to the left. So if you want to make 400/400 and have peak power around 5500-6000rpm but don't want more than 6500 it will work. If you want to make 400/300 and power to 7000-7500 rpm the stocker will be better.

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Originally Posted by Scargod View Post
DAVCS, EJ257 with Kelford 220-C cams (272/268 for DAVCS) just as a reminder.
I rebuilt (refurbished) my AVCS sprockets. I was told they were very responsive.

Application: My design for the build was 450'ish HP and 8K RPM range (mainly because of the turbo being weak down low). I'm a bit disappointed that the torque is so low but once it gets moving it is just even acceleration through the gears! It's fun. I also wanted to build something where if 450 was good then I'd try for more. I wanted a strong build capable of 500. Here's the catch though. I used the best ARP studs but I'm not closed deck and I'm running stock head gaskets. I know it can take 26 PSI but I didn't want to put that much strain on it. I want it to last 40-50 hours. Looking back, I probably could have gotten away with 93 octane gas and still made good power. Matchbot says my torque should have been about 440~450 and I do not know how you equate or calculate torque loss. Instead it held pretty steady at 370~380 T.

I wanted a reliable track car. The '08 STi has aero and weights only 2,800 lbs. Close-ratio gearbox and racing diffs. Check out the IWSTI journal link.
I'm not into drag or even autocross. Just playing with the big boys and trying to keep up. I used to have racing licenses. BTW, someone could buy my car if they're interested... I have an 818R to finish.

I do not have that kind of data logging info right now. I could get it next time out. I don't believe the tuner keeps that kind of log once they're finished.
Yes, I poured over the BW Matchbot numbers and turbo specs before I started. I knew it would be in a reasonable % of wastegate mode over much of the range but the power numbers looked optimistic so I went for it. Especially in the 4,500 to 6,500 RPM range the compressor efficiency numbers look great. I've actually been happy that the 8374 made 300 FPT by 3,500 and 390 by 4K. Had the turbo not died at 6,700 it could have made that flat torque over 4,000 RPM's with no increase in boost!
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Originally Posted by Scargod View Post
Thanks, I guess. Longevity and "enough power" was my goal. Talking to the tuner about this on Monday did not provide many answers. He did not dial it back intentionally at the end.

WHich begs the question: I have a badder one in the works, but it is not closed-deck either. Can I safely get to 500 WHP with it?
Quote:
Originally Posted by Scargod View Post
Other than I probably need to try cranking up the WG actuator pressure have we come to any consensus at all?
You seem to have a good setup, and should be able to make more higher rpm power as is or with small mods. Personally (and I am assuming there is no other issues) I would just do a bigger dp and retune telling him you want high rpm power and keep torque in the 320-340 range flat to as high as it will go and don't concentrate at all on spool or low rpm. If you're on the track at 3000-3500rpm that is driver error, you should have downshifted

I would rather do sleeves than closed deck tbh for a track car, keep the coolant at the top of the cylinder where combustion is taking place, it will run and tune much better, and especially be safer at high rpm loads. 500whp/350wtq should still be fine on stock block on track because you are no overloading with torque, if you were at 450wtq you would have a shorter life if you used that low rpm power range on track repeatedly.

Your eventual goal of 500whp at 8000rpm is perfect and will make your car much faster than most, keeping you a gear lower than typical builds.

Just to compare, here is a friends car, 08 with stock heads and cams, stock intake mani, 94 octane pump gas, old school gt3076 at 24psi, with a cosworth block. Stopped at 7300 due to valve float so torque was left to fall a bit. This is why I suspect your tuner did not get the most out of your setup as it compares at redline to a much smaller turbo with no headwork or cams. Notice it does start to fall around 6800 which is typical for a stock davcs car from personal experience. This is why is suspect your cams gave you some extra rpm however your intake pulled it back. Add the restrictive dp, possibly cam and ignition timing left on the table and you have a recipe for your graph... or I'm completely wrong and there is some other issue


Last edited by blurred; 01-22-2018 at 07:08 PM.
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Old 01-22-2018, 06:42 PM   #34
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Well I'd say it depends on what it takes to hold boost up top. If he has to add a bunch of wastegate duty after 6700 I'd try tightening up the wastegate and maybe block off the bpv to eliminate that. If not then it seems like it needs a bit more dyno time.

Does your up-pipe have provisions for external wastegates? To me it doesn't seem like the turbine housing and IWG are the problem but just wondering.

Or maybe you just need a cosworth intake manifold.

Last edited by jamal; 01-22-2018 at 06:51 PM.
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Old 01-23-2018, 10:52 AM   #35
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Well I'd say it depends on what it takes to hold boost up top. If he has to add a bunch of wastegate duty after 6700 I'd try tightening up the wastegate and maybe block off the bpv to eliminate that. If not then it seems like it needs a bit more dyno time.

Does your up-pipe have provisions for external wastegates? To me it doesn't seem like the turbine housing and IWG are the problem but just wondering.

Or maybe you just need a cosworth intake manifold.
Wastegate duty is (according to Matchbot) only about 70% up there. Sure, for that brief time between 6,700 and 8K I could do 24-26 PSI without issue.

I fabricated my own 321 SS twin scroll up-pipe with V-bands to the Full Race headers. I could easily go with external wastegates but that defeats the purpose of the turbo, don't you think? I'd probably go Garrett if I did that.
FYI, I've had good luck with previous engines with stock location use of a Blouch 2.5 XTR TS. I did buy into the sales pitch that the BW EFR was that good with internal WG.
Lastly, the Cosworth intake doesn't flow any better than what I have. The runner length may be quite different, but I was trying to bolster the bottom RPM range with the intake, twin scroll and .92 turbine (plus lots of light stuff in the engine and drivetrain) with the thought that with the big turbo the top end would be easy to attain.
I see I'm not the only one suffering from "fall-off". I've looked at 450'sh builds on EFI's dyno database and, though few have torque as flat as mine, a number fall off around 6.5-6.8K.
Granted most were smaller turbos but this one had an 8374 and had a steady decline in torque with no abrupt fall-off of torque and no decline in HP.

Last edited by Scargod; 01-23-2018 at 06:47 PM. Reason: correct misspelling.
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Old 01-23-2018, 07:57 PM   #36
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Granted most were smaller turbos but this one had an 8374 and had a steady decline in torque with no abrupt fall-off of torque and no decline in HP.
Do you know what turbine housing the other guy has? Im not sure whether you are happy with the other 8374 example or not? The obvious difference is that he has EWGs.

The other example is very responsive, I just dont think you can have a huge midrange like that and expect it to hold high into the rpm.

I agree with Chris that the turbine housing is too small. A twin scroll 0.92 is roughly equivalent to a 0.75 single scroll which is quite small for such a large turbo.
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Old 01-23-2018, 08:38 PM   #37
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Harey, I entirely missed the fact that the 8374 had external wastegates. Must be 1.05 or 1.45. I'm trying to contact the guy...
Looks like I'm doing more with less boost till we get to 6,700 RPM. I guess that's when you're saying my .92 AR IWG turbine is dying.

If all this supposition is accurate then I think it begs the question: What should I change? 1.05 turbine with EWG? I am not wanting to go a lot higher with the power because of reliability and higher costs. As I said, I want to flog this thing for 40-50 hours on the track per rebuild. I've got 20 hours on it and it's fun and solid.
I am also not married to the 8374 but I have been relatively impressed by it. I'm not sure what would be a better overall turbo for my goals in that I want to keep boost under 25.
Thanks for the input.
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Old 01-23-2018, 09:02 PM   #38
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I am not wanting to go a lot higher with the power because of reliability and higher costs.
You'd be better served by running a turbo more in line with your power goals to retain decent mid-range. You're engine specs follow high RPM power targets, which this turbo/housing/A-R/IWG are not suited for.

Another thing to consider is that a more free flowing turbine/exhaust will make more power on less boost, with less EGTs, and likely less timing. If anything, going that route is going to improve longevity vs where you're at now.

Generally, for track applications we recommend the larges A/R you can get. This will give you the best VE for the RPM range you're using (upper RPMs and track use).

A small A/R can choke any turbo depending on the hot/cold flow 'balance' and usage. We ran a GTX3576 with a 0.63 A/R and it choked up high and was boost restricted (more boost did not make more power). We were wanting a wall of torque for auto-x, which it did but made poor power for the turbo's capability.It comes down to the simple fact that if you can't remove the exhaust gasses, you can't force more boost in. Going to the 0.82 A/R we picked up +50whp with a negligible change in spool. We made this power making less boost than with the smaller housing, and it pulled hard to the limiter (stock heads). This was a street mostly setup (some auto-X and drag), and I would definitely recommend a 1.06 A/R for a track car.
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Old 01-23-2018, 09:24 PM   #39
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Looking at the options for the 8374 and the larger turbine housings 1.05 and 1.45 only come in EWG. So doesnt look like you have too many options. If you do want to go a larger housing than you will have to convert to EWG. I think it also gives you an indication that even they dont think IWG will flow enough on the larger housings.

This should really help though both in the high rpm power but most importantly longevity as Chris said above.

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Old 01-24-2018, 08:41 AM   #40
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When you say preload of the WG was to spec I'm not sure what you mean. The range of WG preload ranges from 2 or 3 mm to 10 mm based on the boost you are trying to achieve. I had to run at least 6-7mm of preload to get 25 psi with my 7670 so don't be afraid to add pre-load but you will have to retune boost afterwards. Its all in the EFR document.

Quote:
Originally Posted by Scargod View Post
First off, thanks to everyone for their advice. I'll try and answer latest relevant questions/concerns.
First, given that the majority of comments focus on the exhaust, I still wonder how it has such a dramatic downturn in power?
If the downpipe or turbo-back is choking it then why is it no less dramatic at lower boost/power?
If the wastegate is being blown open all of a sudden then that might be a credible argument. Whether it's 23.0 PSI or 20.6, it still falls off at about the same rate and same RPM spot.
Preload on the WG actuator canister was to spec: 3mm (3 nut turns)
I used the Borg Warner BCSV (boost control solenoid valve) that came with the turbo (no other ECBS used),
and YES, it is internally wastegated, as in stock wastegate.

I don't want to kill the messenger, and I am somewhat of a neophyte in this area, but the BW EFR line of turbos is for racing and high-performance applications. Unless there is something defective I don't see why it shouldn't perform satisfactorily in this application. As mentioned, it's just beginning to work at the point where it drops off. There's lots of wastegate action on the low and high end. Matchbot says it's 38% at 6,800-7,200.
I chose twin scroll and the smaller turbine so I could get a better low RPM response. I don't understand how that could be causing what's happening (in such a dramatic fashion).
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Old 01-24-2018, 10:03 AM   #41
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When you say preload of the WG was to spec I'm not sure what you mean. The range of WG preload ranges from 2 or 3 mm to 10 mm based on the boost you are trying to achieve. I had to run at least 6-7mm of preload to get 25 psi with my 7670 so don't be afraid to add pre-load but you will have to retune boost afterwards. Its all in the EFR document.
That 3mm I quoted came from the EFR setup documentation. Was not discussed during the tune. I just set 25 PSI as my desired limit.
Not sure if I want to spend $300+ for a retune or that money towards a new turbo.
What would be a good fit? GTX3582R? Do I want to forget twin scroll? Definitely will not go back to IWG turbo.
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Old 01-24-2018, 11:08 AM   #42
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What would be a good fit? GTX3582R?
Single scroll GTX3576-R Gen II with a the big A/R Tial would exceed what you're making now for power and definitely push power out higher on the heads you've got with a bigger A/R Tial.

Here's an older Gen I on our Spoolinator setup with the mid-size Tial housing on pump 93. TMIC, stock cams, valve size, etc... to give you an ideal of what the turbo is capable of on pump 93. Made 600whp on E85. The 3582 adds a good bit of lag.

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Old 01-24-2018, 02:24 PM   #43
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Since I'm shameless about capitalizing, I have the piping from a spoolinator kit sitting in my shop. I'd be happy to part with it if you're interested, sans the 3067 also sitting there. https://forums.nasioc.com/forums/sho....php?t=2847982
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Old 01-24-2018, 06:15 PM   #44
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Originally Posted by subydude View Post
Since I'm shameless about capitalizing, I have the piping from a spoolinator kit sitting in my shop. I'd be happy to part with it if you're interested, sans the 3067 also sitting there. https://forums.nasioc.com/forums/sho....php?t=2847982
I was thinking of the 4088R. Then Chris suggests the GTX3576-R Gen II with a the Tial turbine.
Steve H. has the rotated Spoolinator setup with an ATP 3076R. The Spoolinator setup looked nice.
I might be interested in the Spoolinator pipe you have. Will it sit atop a stock FR up-pipe?

Chris: Would the Gen II be comparable spec's as the older Gen I Garrett with Teal turbine housing you speak of?
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Old 01-24-2018, 09:23 PM   #45
KillerBMotorsport
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Originally Posted by Scargod View Post
Chris: Would the Gen II be comparable spec's as the older Gen I Garrett with Teal turbine housing you speak of?
4088 is waaay big for what you're trying to accomplish power wise. It would be very laggy in comparison.

The Gen II will make ~5% more than a Gen I with no change in response or torque. There really are no downsides from a performance perspective, just the additional cost downside.
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Old 01-24-2018, 11:59 PM   #46
jamal
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You know, now that I'm looking at some other plots, you do have a pretty nice torque curve, and it's probably going to dip a bit to redline no matter what. You're past peak VE and compressor outlet temps are rising.

I think if you swapped on a 3076 you wouldn't see much change, and your curve would shift to the left and probably drop off worse to redline. Looking at both compressor maps they are closer than I first thought, which is pretty impressive given the wheel on the garrett is 7mm smaller. The efr is marginally more efficient and has a lot more left.

Still some more troubleshooting couldn't hurt and at most I'd go to external gates. That's probably where any gains would actually come from if you swapped to the garrett.

Last edited by jamal; 01-25-2018 at 02:50 AM.
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Old 01-25-2018, 12:51 AM   #47
Harey
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May as well sell the car and start again..... LOL

I agree with the one of the earlier posts, you cant just expect to pay a standard tune fee of $500 or whatever for a full custom build like this. Need to find a good tuner and allow him some time to work. He will be able to tell you if the housing is too small. Give him full specs on the car and tell him what you want out of the car. Might be 2 hours the first time, then he will tell you to do X, get that done and come back, might be another 3 hours tuning then see how it goes from there etc. Need to get the tuner to get involved in the setup.

Last edited by Harey; 01-25-2018 at 12:58 AM.
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Old 01-25-2018, 07:31 AM   #48
kellygnsd
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What platform are you tuned on? Could you add more preload, zero WGDC tables and self tune boost again yourself? Turbo has more in it you just need moar boost. My 7670 F-R kit made 500whp on 91 + meth @ 8000 rpm. No HP fall-off whatsoever running 25 ish psi to redline. It took a lot of preload to get that done though. I'll be going with a dual port acuator and a 4-port BCS this time around. 3mm of preload is not enough on our cars, double that is barely enough. Check out pages 29-31 of the EFR document again that go over setting the preload.
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Old 01-25-2018, 10:32 AM   #49
Scargod
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I am tuned through an Accessport. Rather wished I wasn't at this point. I do have faith in Calvin at EFI. He may not be that experienced with this level of race engine SD tune but he's done lots of Subaru's. That's his strength, I believe.
He spent three hours giving me three tunes, hence the 362, 430 and 467. Usually I get the last tune slot of the day so there's plenty of time. At the start I did have some parameters and goals for Calvin, but I know a lot more now than then. I could have virtually run on pump gas, with that low a boost! Thought it was going to require a lot more boost to make that mid-450'ish HP. We discussed max boost of 25. I was so ecstatic with the easy accomplishment of 467 HP that I did not ask for more based on boost. I was not really paying attention to the end and the fall-off (just thinking it was a safety thing). Last week Calvin said it was not something he did intentional for safety's sake. He did mention the turbine and exhaust but also mentioned other plausible reasons, much as has been mentioned here.
Seems there are some decent VE's to my engine till it starts to run out of turbine...
Here is the Matchbot output I've been looking at. I don't understand a lot of the numbers. I see a -4 for engine delta pressure (under turbine).
I am trying to sell the car and start over...
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Old 01-25-2018, 09:37 PM   #50
Harey
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Wow I was only joking about selling the car. These cars take a lot of effort to setup and you are so close. Also sounds like you have the handling and braking already sorted.

Sounds like you have given the tuner plenty of time. Have you contacted Borg Warner or EFR? How much will they charge to swap housings?

I really think the housing is too small, it's similar to running a gt37 size turbo on a 0.75 single scroll housing which is madness.

Although it will cost a bit to convert to ewgs, the cost of 2 wastegates plus piping it will give significant improvement. Borg Warner themselves don't even sell an iwg option for the proper sized twin scroll housings.

Surely its worth one more go at this car before selling it
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