HarrisRacing

not 100%, but close. It's the A/C compressor clutch - must be something went bad in it because when I turn A/C on at idle, voltage drops like a rock only for that accessory which indicates a huge issue with current drain on that accessory. I installed 3 diodes in the sensing line of the alternator which bumped my voltage to around 14.2-14.3 V while running now - but fuel pressure still dwindles on top which just means I'm out of fuel pump. Turns out I don't think the AEM 380 is up to the task so what I'm going to do it go to twin Walbro 460's in tank very shortly since I already installed -8AN line splitting to dual -6AN to feed my Hypertune rail (preparation for E85 jump). Thank you for asking. Voltage definitely affected my dead times on these injectors which didn't come with a card, so I had taken educated guesses at them (going to go to new injectors anyway so whatever).

Just putting some more links and information. Perhaps an all-in (max wheel speed) 8374 EFR Match-bot prediction for the future? http://www.turbos.bwauto.com///////aftermarket/matchbot/index.html#version=1.3&displacement=2.75&CID=167.805&altitude=0&baro=14.706&aat=75&turboconfig=1&compressor=83s75&pt1_rpm=6000&pt1_ve=120&pt1_boost=31&pt1_ie=90&pt1_filres=0.5&pt1_ipd=1&pt1_mbp=1.7&pt1_ce=64&pt1_te=70&pt1_egt=1650&pt1_ter=3.34&pt1_pw=30.09&pt1_bsfc=0.55&pt1_afr=11.5&pt1_wts=300&pt1_wd=83&pt1_wd2=74&pt1_wrsin=69033&pt2_rpm=6500&pt2_ve=121&pt2_boost=27&pt2_ie=90&pt2_filres=0.5&pt2_ipd=1&pt2_mbp=1.9&pt2_ce=62&pt2_te=70&pt2_egt=1650&pt2_ter=3.21&pt2_pw=32.07&pt2_bsfc=0.57&pt2_afr=11.5&pt2_wts=320&pt2_wd=83&pt2_wd2=74&pt2_wrsin=73635&pt3_rpm=7000&pt3_ve=121&pt3_boost=24&pt3_ie=90&pt3_filres=0.5&pt3_ipd=1.1&pt3_mbp=2&pt3_ce=62&pt3_te=70&pt3_egt=1650&pt3_ter=3.07&pt3_pw=35.07&pt3_bsfc=0.58&pt3_afr=11.5&pt3_wts=340&pt3_wd=83&pt3_wd2=74&pt3_wrsin=78238&pt4_rpm=7500&pt4_ve=118&pt4_boost=22.5&pt4_ie=90&pt4_filres=0.5&pt4_ipd=1.2&pt4_mbp=2.1&pt4_ce=60&pt4_te=70&pt4_egt=1650&pt4_ter=3.05&pt4_pw=35.26&pt4_bsfc=0.59&pt4_afr=11.5&pt4_wts=368&pt4_wd=83&pt4_wd2=74&pt4_wrsin=84681&pt5_rpm=8000&pt5_ve=115&pt5_boost=21&pt5_ie=90&pt5_filres=0.5&pt5_ipd=1.3&pt5_mbp=2.1&pt5_ce=60&pt5_te=70&pt5_egt=1650&pt5_ter=2.98&pt5_pw=36.87&pt5_bsfc=0.65&pt5_afr=11.5&pt5_wts=400&pt5_wd=83&pt5_wd2=74&pt5_wrsin=92044&pt6_rpm=8500&pt6_ve=105&pt6_boost=21&pt6_ie=90&pt6_filres=0.5&pt6_ipd=1.5&pt6_mbp=2.2&pt6_ce=59&pt6_te=70&pt6_egt=1650&pt6_ter=2.98&pt6_pw=35.39&pt6_bsfc=0.7&pt6_afr=11.5&pt6_wts=400&pt6_wd=83&pt6_wd2=74&pt6_wrsin=92044& And a dyno comparison of my 10 psi and 17 psi runs that I put together in excel.

I was able to perform Match-Bot calcs for my turbo prior to selection and it is well documented on this forum. It is one major reason I went with Borg Warner over a precision. Their data is about 5X's of what is offered from Garrett and about infinityX's what is offered from precision. As a mechanical engineer, I just really like the data / planning stages of the build. So if "knowing limitations before hand" is highly important then I would venture to say choosing a Precision would be an absolute last resort IMO.

Or installing too small of an EFR will cause overrun even on pump. I think on a 3.0L you could be at the upper limit of an 8374 at only 22 psi and 8k rpms FYI. The material is super light, and super oxide resistant at extremely high temps, but has extremely low ductility. Meaning it will not stretch...only perform until fracture (rpms of the turbo are the tensile ductility test). EFR manual states this several times as the reasonable limit. This is extremely similar to why the factory ceramic turbines explode at a certain RPM (wow another high-heat, lightweight, low ductility material). It was either that or they become un-bonded from the shaft, but no one knows because they turn into dust when they do finally explode. On my initial MATCH BOT 2.75L projection, I found that I could get into the 30-32 psi range in the mid-range of rpms (5-6800) but would have to taper off boost to keep from over-spinning on top end (down to 22 psi @ 8,500). So you take the rally car approach where you spin the turbo to max as soon as possible (mega torque) then ride this same power level (ie-turbo rpms) all the way out to redline (to keep from blowing up the turbo). https://en.wikipedia.org/wiki/Titanium_aluminide

FYI. Just drove my car to work this morning in a little over a week (don't know if you've heard on the news about all of the flooding in my area of the world, but thank God we are OK - lots of our friends were not so fortunate). I trimmed my fuel map a good bit leaner to correct my AFR after fixing my voltage issues and the car is significantly smoother to drive again. My final PUMP GAS assessment (and I'm on a 2.75L stroker). The 8374 EFR .92 IWG is a very drivable turbo for a streetcar. It starts coming on STRONG at 3700 rpms and pulls all the way till I bang the limiter which is currently at 8k. At 20 psi boost I could easily autox the car and it's definitely responsive enough to do this. I can 100% vouch that I am HAPPY for the amount of power it makes now and the powerband of my engine. I built my motor to go 9k so at the current 8k limit I'm very pleased with the delivery and response of the turbo. I'm even more pleased that there is still 10-15 psi of boost and possibly 150-200 more HP left in my setup when I move to E85. For pump gas SOME may think this powerband is a bit laggy, but hey...the RB is NOT a big motor and you WILL be giving up lots of power if you size something that magically spools at 3k rpms. They are currently building an E85 station RIGHT BY MY HOUSE that is supposed to be completed in November so get ready for some cold weather and high-boost E85 numbers coming soon. I'll save my pennies for a couple of extra fuel pumps and some GIANT injectors and let you guys know how this thing really performs. But don't forget it made already on 93 pump: 376 whp on 10 psi 464 whp on 17 psi (88 whp gain from only 7 psi boost) - also ran 11.70 @ 120 with this tune. I'm estimating (and will dyno again soon) 500 whp on 20 psi on 93 pump with conservative timing. And when I put in E85 I'm sure the sky is the limit (or Trans as I am on a bone-stock R32 box currently). I'm kinda with you Lithium...It gets strange just looking at dyno numbers from "X" car on the internet. I provided logs and videos correlating them, and others posted driving videos of their cars in competition (so did I), which should give plenty of information for those looking to go bigger. I personally would not put a precision on my car for the reason that I think the EFR has more to offer for the money and more engineering data behind it should I make changes in the future (the wheel speed attachment point is one GREAT feature to start with). That being said, I understand the guys with -5's not wanting to swap their setups and I understand 100% the labor, time and money involved in that swap...I likely would NOT remove -5 turbos if they were on my car - but I went from stock turbos to the 8374EFR and honestly with the: Integrated BOV, integrated wastegate, oversized ball bearings, CNC compressor wheel, Gamma-Ti exhaust wheel, stainless steel housing, V-Band ready compressor housing, and wheel speed sensor ready boss - it's a GREAT value in a very reliable and responsive turbo. Not that I would do this, but the simplicity that I have with my setup is such that in 45 minutes I could 100% remove my turbo, wastegate, intake, and blow off valve from my car and bolt on the 1,000HP 9180 in it's place <-- this was added bonus for me. I stayed with the IWG .92 because I got the turbo for $1640 USD shipped straight from Ebay (seller HAD to have listed the price wrong, but they honored the sale). Think about it...that's a world-class BB turbo, wastegate, and BOV for less than the cost of most other singles before you add a BOV or single wastegate to them (and lots of guys are running twin gates). So add in a 6 boost manifold (you guys all get them for less than I do) and honestly it was a no-brainer great deal on this setup even compared to me going -5's with new gaskets, lines, hot pipes, etc.

This looks to run very similarly to my car response-wise BTW.

^^^^ Please tell me you have some 17-18 psi data!? I'm assuming E85? I'm glad to start seeing other "real" numbers. I mean this is 620 whp on 25 or so PSI. I am hoping to see 550 whp on my car at the same boost on the 2.75L. I'd love to compare logs to this thing on the street to see how far I have to go. Also I'm on the Poncam A's (260 and 256 ex) and found that closest to 0-0 made the best results for me too. I tried getting them closer together and it felt "stumpy" in the mid range. Excellent results!

Found it. White line is boost control output. Notice it's 100% while it spools until it hits my commanded boost number to start open loop control. You can see its pretty linear with RPM to maintain my 18 or so psi boost.

Yes IWG. And yes increases pretty much linearly. I posted a log on here not far back. If you download the haltech datalog viewer you can see my output duty cycle on the logs under "boost control output" (which is controlled by open loop) and also my "base duty cycle" (which is my start point before controls - basically my duty cycle map). Just double click those to populate the charts and add the RPM THE same way to see what mine is doing on the high boost IWG BW actuator set at 6 turns from base.

Yep. No way to keep boost high enough on top end without changing duty cycle throughout rpm. Mine is almost linear on duty cycle for rpms after it onsets.

Dropping boost on top? Mine was on the medium cannister. It's almost as if these things should ship with high boost cans factory. Was cool to see my car make 376 whp on 11 psi though!

LOL yeah looked like an SR20 to me. -5s are a bit big for that. So is an 8374 for that matter (imo)

Treadstoneperformance (TRE) you can weld 3" on the inside of theirs and 3.5" on the outside. 3" assembly: http://www.treadstoneperformance.com/product.phtml?p=68259&cat_key=613&prodname=Borg+Warner+EFR+Turbine+Housing+V+Band+Clamp Both 3 and 3.5" flange: http://www.treadstoneperformance.com/product.phtml?p=2542&prodname=Borg+Warner+EFR+Turbine+Housing+V+Band+Flange+3.5%22+Downpipe I would not waste my time going 3" again

It sounds like it would be a great combo. Enjoy it. This thread is far too old and far too diluted to complain about, but I am trying to still provide what data I can to help those make an educated decision.

switching sounds like a good idea. I actually had pretty good results from open loop at first, but now I'm running full closed loop. It is a little frustrating in that you can get it perfect for fast shifting then it's weak on the low ramp or vice versa. The alternator voltage seems to have helped my fuel pump keep up with power (an issue I've been having), so I was afraid to try much leaning or boost until I get that sorted.You can see my request and actual outputs in that log (I think I have everything checked). Keen (as you guys say) to see your results.

oh and another thing I noticed. The 3x diodes I put in the alternator sensing line really helped my voltage. Which also made my car too rich pretty much everywhere. I need to reset my dead times at 14+ V (hadn't been able to do that yet).

I'm on it before the video. I trimmed the video using the go pro (15 sec clip). I'm whistling because I was already on it and the car REALLY didn't like to be that low (I never have tuned full throttle from 1k). But I can put up the whole video if you want. The log is 100% complete and will back it up totally. I honestly have no reason to lie and I don't like to play in the 20-21 psi range because I'm still on the Haltech factory MAP sensor (internal only good to 22 psi). Also on 255/40/17 hankook RS3's if that matters.

Done. Internet racing at it's finest LOL. I must say it's really neat that we can even do this so quickly and easily separated by such long distances! Ended up with almost exactly 4.5 sec from 5k to 8k. Remember it's HOT here. I live in Louisiana zip code 70508. And sorry seems to have a bit of a spike in the mid range. also a little lagniappe for you. https://www.youtube.com/watch?v=arlX2DfbLoQ 3rd gear pull.zip

Cool. I can do that now. I'm only 17-18 psi...may try 20 if it takes it.

I'm digging it. I really would like some pull videos to compare to my car. It's still hot as hades here (was 95 deg F today), but I'd really like to run our videos back to back and compare setups. You know my whole setup. I'm curious to see yours.

All of their response is not as strong as mine or yours though. You have a stand out -5 car from what I'm seeing compared to those.

I'm throwing the -5's back into the ring here for a second 1) Found this dyno of a "fully built, high-rev ready, on 17 psi. 463 whp 2) Same car on 20 psi: 544 whp 3) Seems to be different car (S13) on 20 psi. 4) All stock R32 internals with -5 turbos at 18 psi. 500 whp (really looks like 492 with a smoothing hiccup at the end) so I looked close at the dynos and found a couple of things: My car beats them all HP to the wheels on initial spool down low in the rpm range of 3500-4700 rpms. Then those at the similar boost levels are around the same HP (which is depressing because I'm a stroker with slightly more displacement) from there to about 6k where they all start gapping me in power. Granted I NEVER touched my ignition timing up there on my dynos so I'm likely leaving a lot of power on the table still. Also I'm now convinced that the 3" exhaust is hurting me up top (and perhaps even the .92 IWG housing). I have read a lot about the IWG setups and backpressure. At high boost and high rpms (ie high EMAP situations) each 1 psi of exhaust pressure can equal up to 2-3 times the turbine/manifold pressure since this is multiplied via the physics of a turbo volute. I did notice ALL of these cars are running 3.5" exhaust. So yeah...that.

I am unfamiliar with the KM to HP conversion but I would guess it's the same, right? Is your HP at the wheels? In all honesty I wouldn't spend the money changing it, as it looks like solid yet slightly high-end powerband to me. If anything spend the money on a V-cam setup and gain some bottom end that way. I mean you are on a T3 manifold so it would take significant money changing things at this point. Also the caveat is that the dyno I have is old and doesn't represent the spool I've been able to get out of the car with bottom end changes lately. I have posted my boost threshold data lately. I too wish there was a "perfect" RB26 street turbo between the 7670 and the 8374 but it doesn't exist (yet). Apparently our high rpm band hurts what we can bolt on. So far I'd say any of the following fit a higher boost (E85 or WMI) street car pretty well: Precision Gen 2 6062 Borg Warner 8374 EFR (,92 or 1.05) Borg Warner S300SXE 8376 (little more lag and little higher rpm power than 8374 journal bearing turbo) GTX35R Garret -5 twins (These really aren't bad turbos IMO). I think all of these singles will beat the -5's in overall power and will be similar (if not better in some cases) in response, but that comes at a price...real money and a non-stock appearing setup.

If going 7670 I would stick with a 2.6L and stock cams. Turbo will be at maximum speed for sure and you will need to add a road rage gauge to make sure you don't destroy it from overspinning. I wouldn't suggest running the boost over 20 psi over 7k rpms. I bet it will *just* make your HP number though. It would be a VERY fun daily driver. Reason why I say stock cams is because you will start to choke that turbo on top end on the exhaust side and larger (ie-overlapping) cams will only make the backpressure contamination worse in the cylinder. When I was comparing the 8374 to the 7670 I think I found that the 7670 should hit full boost 500 rpms sooner than the 8374 and make similar power up until around 7k where the 8374 will continue to feed the motor. Of course I was probably looking at 2.75L at the time so I'm sure a 7670 on stock cams and 2.6L is a good choice for a street car that occasionally wants to turn up the boost.

^^ Looks pretty quick! Took the liberty of converting my dyno data from 10 psi and 17 psi and putting in excel graphs. BLUE lines are data associated with 17 psi pull, RED lines are data associated with 11 psi pull. Boost is in PSI, but is multiplied by 10 for scaling purposes (so 100=10.0 psi and 200=20.0 psi). Also I believe the turbo would have made 380-385 whp if revved to 8k rpms on the 11 psi pull...I was hesitant at first because this was literally the first dyno pull. It did make 371 whp at 7600 rpms though.