N54Tech.com - International Turbo Racing Discussion
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Default 07-01-2016, 01:31 AM

I think I'm going to amplify the data I've already posted with a bit more. You see, I had a sneaking suspicion there'd be some "push-back" on my findings, no matter how carefully controlled the road testing was. So we booked time at the dyno and took some measurements. Here's the car, happily strapped down to the rollers at Portland Speed Industries:




And here is the comparison. Before and after inlets. And just to give the inlets a bit of extra help, the car was running WMI injection along with E50. On the previous dyno the car was running just E50.




Zero power improvement after 4500rpms, the critical period where higher capacity inlets should be earning their keep. Then, to add a bit of added color to these findings, we pulled up another dyno run on the DynoJet facility's database. It was a car that was virtually bone stock. All it had was an upgraded in-tank fuel pump, E30 fuel in the tank, and a terrific Wedge Performance flash. As a reminder, here are the mods of our test car: Open element air filter, prototype turbo inlets, ******* exhaust, WMI injection, E50 fuel, Stage2 LPFP, upgraded FMIC, 4bar TMAP, throttle charge pipe & JB4.




Food for thought. And more lively discussion.


Doug Harper
FrankenTurbo



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Cloud9Blue Cloud9Blue is offline
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Default 07-01-2016, 02:13 AM

Quote:
Originally Posted by doug@frankenturbo.com
I think I'm going to amplify the data I've already posted with a bit more. You see, I had a sneaking suspicion there'd be some "push-back" on my findings, no matter how carefully controlled the road testing was. So we booked time at the dyno and took some measurements. Here's the car, happily strapped down to the rollers at Portland Speed Industries:




And here is the comparison. Before and after inlets. And just to give the inlets a bit of extra help, the car was running WMI injection along with E50. On the previous dyno the car was running just E50.




Zero power improvement after 4500rpms, the critical period where higher capacity inlets should be earning their keep. Then, to add a bit of added color to these findings, we pulled up another dyno run on the DynoJet facility's database. It was a car that was virtually bone stock. All it had was an upgraded in-tank fuel pump, E30 fuel in the tank, and a terrific Wedge Performance flash. As a reminder, here are the mods of our test car: Open element air filter, prototype turbo inlets, ******* exhaust, WMI injection, E50 fuel, Stage2 LPFP, upgraded FMIC, 4bar TMAP, throttle charge pipe & JB4.




Food for thought. And more lively discussion.


Doug Harper
FrankenTurbo

You gonna post a proper log showing the WGDC or PWM before or after??? Of course not...

Your data are a joke, you are done here...


09 BMW E92 335i: EFR 7670 / Motiv / AP Racing / Wavetrac / TC Kline [Full Modlist]
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Weehe Weehe is offline
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Default 07-01-2016, 05:45 AM

Yeah pretty much. I had a shred of hope left, not anymore. I'm guessing you also think RS4 or other inlets on the B5 S4 do nothing and everyone is wasting money on them.
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Default 07-01-2016, 02:19 PM

Quote:
Originally Posted by Cloud9Blue
You gonna post a proper log showing the WGDC or PWM before or after??? Of course not...

Your data are a joke, you are done here...
Was going to ask this, but beaten to it.


2010 335ix - hybrids, cp, ic, inlets, outlets, jb4, pi, fuel-it stg3, backend flash
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Default 07-01-2016, 11:55 PM

Look Doug, (most) people are genuinely trying to help you.

When you refuse to provide the data (logs with wgdc and pwm), it makes you seems arrogant or at least stubborn with your head in the sand.

If you want to have a business on this platform, you are going to have to accept we are not going to be duped and have some very bright people on this platform.


2007 n54 e90 sedan (1/07 date), JB4 G5 ISO - Map 3, BMS DCI, BMS Trunk Tank Meth Kit - two nozzle - CM7/CM10, BMS OCC, MHD Trebilia Flash, e60 (5 gallons of 93 and 11 gallons E85), Stage 2 from Fuel-It, VRSF 7" FMIC, N54tuning.com V1 **, ER Charge Pipe w/Tial BOV, NGK Iridium (one-step colder) plugs, N20 TMAP Sensor, RB turbo inlets, VTT outlets
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Default 07-08-2016, 02:21 PM

No additional test data to present just now. That's because we've been busy filling orders during this busy time of the year.

Out go yesterday's shipments:




And here's an example of how our customers feel when they get their awesome FrankenTurbo.




That's a happy face. Even the Danish postal service guy feels the love. And soon enough this community can count themselves in for exactly what we have offered thousands of our customers worldwide.

So turn those frowns upside down, people.

Thanks

Doug Harper
FrankenTurbo


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Default 07-08-2016, 03:30 PM

This is like a bad blog / advertisement, as opposed to a forum post with mutual discussion. This train has gone off the tracks.


2010 335ix - hybrids, cp, ic, inlets, outlets, jb4, pi, fuel-it stg3, backend flash
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Default Cranking up those wastegates - 07-17-2016, 12:52 AM

An old trick to get more output from a turbo is "cranking the wastegate". What that involves is making use of a turbo actuator's adjustment nuts. Intended for use solely in fine-tuning an actuator's cracking pressure and rod lift, the adjustment nuts can also be "hacked" to amp up a turbo's rotational speed.

The N54 turbos have such adjustability, and historically it's been used to patch wastegate rattle issues. But I have no doubt a number of people looking for power have also put the wrenches to the adjustment nuts. Here's a look at the N54's bank #2 turbo, with the arrow pointing out the notched actuator rod's adjustment point:



The trick here is to shorten the distance between actuator and the wastegate's clevis pin. On a standard, boost-controlled actuator this would raise the preload on the actuator's spring, which increases the actuator's clamping pressure. But the N54 turbos are vacuum actuated and don't rely on springs for clamping pressure. So the whole notion of "cranking" shouldn't apply here.

But there is an alternative impact possible from making this adjustment: it limits the wastegate valve's degree of opening movement. And a reduced opening for the exhaust gases would redirect some flow to the turbine rotor. So if the wastegate valve is getting blown off its seat as it does on traditional actuators, then that reduced opening might net something more from the turbos. This seemed worth exploring, so we got to work.







There is not a lot of room to access the adjustment points the turbos. Things are so tight on the bank #1 turbo (where the actuator sits between the turbo and the engine block) that we found it much better to remove the c-clip securing the actuator clevis, then spinning the clevis up on the adjustment threads. Eventually, each turbo could be adjusted 8mm before the adjustment rods bottomed out inside the clevises. We then dropped the car back down and took it straight to our favorite testing spot. Here's a look at the before/after:



Compared to a previous run taken at the same IATs, boost is significantly up. Enough so that the JB4's PID control algorithm intervened. But what about airflows? Are they up as well?




Yes they are.

So at this point it seemed pretty clear that the reduced actuator gamut must be delivering benefits. While being blown open by the exhaust gases, it could not open as wide as before. And that means the hack worked. That is until we pointed a camera at the actuator's behavior during boost:




The wastegate barely budges at any point in a 1500-7000rpm pull. But for a brief crack of the valve at boost onset, it's sealed as tight as a drum. So if this mod is indeed doing anything, it's not because the wastegate can't open as much as before. Instead, the improvement must come from the changed position of the diaphragm within the actuator assembly. The already-potent forces of ~25 inHg vacuum on the diaphragm are leveraged more at this setting.

So how about POWAH? Improvements? Well, not really. Aside from an optimistic report from the highly-unreliable "butt dyno" at boost onset, the 4200-6500rpm rev sweep is basically unchanged.




But the change in boost response is undeniable. This hack raises the turbos' output. Enough to make a worthwhile difference? Not really, probably. But I'd certainly say anyone going through the laborious process of upgrading inlets should consider lumping in this mod at the same time. With any luck, adding in this hack could salvage something from the otherwise useless exercise of an inlet upgrade.

Thx

Doug Harper
FrankenTurbo




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AbacusRacingN54 AbacusRacingN54 is offline
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Default 07-17-2016, 05:21 AM

Quote:
Originally Posted by doug@frankenturbo.com
. With any luck, adding in this hack could salvage something from the otherwise useless exercise of an inlet upgrade.

Thx

Doug Harper
FrankenTurbo


So wrong on many differant levels
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ShocknAwe ShocknAwe is offline
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Default 07-17-2016, 06:50 AM

Pushing more boost for the sake of more boost just creates heat. The energy from the extra pressure has to go somewhere, so it just converts to heat. A lot of heat. So basically you're advocating making the system less efficient. Bad mod.


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Default 07-20-2016, 09:27 PM

So after examining the air intake side of the turbochargers system, I thought it might be worthwhile to have a look at another under-appreciated stock component: the turbos' outlet pipe. Here'a a glamour shot of the motor that shows this pipe as it runs from the turbos to the intercooler:




So why is this simple aluminum pipe so unloved? Reading through public posts here and elsewhere it sure seems the jury is in: they're woefully inadequate. They're restrictive! Wheezy! Nothing can get through these miserable things!

Really? So once again the aftermarket has weighed in to find a colossal screwup by the BMW engineers. Well, I decided, I had to see this for myself. So we took one of these and prepped it for some data collection. One bung here to gather turbo-outlet pressures:




...and another here to gather turbo outlet temperatures:




The choice of the sensor locations was deliberate. The bank #2 turbo has to push through a greater length of the TOP (Turbos Outlet Pipe), so pressure drop between that location and the intercooler inlet will be at its greatest. The IAT sensor located at the bank #1 turbo has a much shorter distance between it and an IAT sensor at the intercooler inlet. So the benefit of heat loss over that distance is the lesser of the two. In other words, we set this up to be very difficult for the much-maligned stock part.

Who wants to see how it did? ...Nobody? Well, too bad peanut gallery! Here are the results!

First, being the mind-bogglingly assiduous maven of variables controls, here are the boost levels recorded at the car's TMAP sensor way downstream of our testing.




As you can see, the downstream boost levels were very consistent from run to run. So let's see what the boost levels were like in these other locations:

Blue: bank #2 turbo outlet pressure
Red: intercooler inlet pressure
Black: intake manifold plenum pressure




As I'd reported earlier, there is a measurable pressure drop between the intercooler inlet and the manifold plenum. That's to be expected: intercoolers create a restriction in the charge air system. But let's have a look at the TOP's performance. After a few moments of pressure drop at onset, pressures at the turbo outlet and at the intercooler inlet line up perfectly: no performance drop whatsoever from 4500rpms to past redline.

But what about charge-air temperatures? How much of a drop can we expect in that short distance between the bank #1 turbo and the intercooler inlet? Again, the stock part struts its stuff: over 100˚F of temperature drop at redline.




Now obviously it's going to be the intercooler which gets the Gold Star for IATs reduction. The differential from green line to blue line is EE-UGE. But the heat conductivity of that aluminum TOP is undeniable. It's a real asset for the charge air system. And in this testing at stock-turbo performance levels, I see little room for improvement upon this part .


Doug Harper
FrankenTurbo


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Default 07-28-2016, 03:28 PM

On the topic of "wastegate rattle" and the adjustment for it, here are a couple videos.

This first one I found on YouTube. It gives a good explanation of how wear and tear introduces "slop" into the actuator assembly, impacting the wastegate valve's ability to seal completely.




And here is a close-up of the fault occurring to one of the turbos in our own test car:




Shortening the rod length between the actuator and the wastegate arm will remedy the fault.






I'd describe this as a short-term "patch" rather than a proper long-term fix, but it can allow car owners to defer the cost of turbo replacements.

dh


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Default 07-29-2016, 04:04 PM

I did this with my bank two turbo (rear) last week. Took away half of the rattle and changed how the power comes on. Throttle response is snappier, probably because the wastegate is closed farther than before. Drives fine. Works fine. No change in mileage. Tried to do the front turbo but it's a bear, even with the ** out of the way I still couldn't adjust it so I said screw it. I'm already planning on new turbos anyway so this was just something to see how it would do. So far so good.


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Default 07-30-2016, 01:19 PM

A few weeks back I posted logging data that indicated the car's DME would not respond beyond a certain point to software mapping for added fuel. The DME mapping setting in question is called the "Fuel Scalar", which allows for a multiplicative adjustment of the fuel injector timings. Not to be confused with a means to raise the fuel system's maximum fueling capacity, it nevertheless makes it possible to manually compensate for the greater fuel flow requirements of E85 fuel. Raise the scalar by the same multiplier as needed for a stoichiometric burn and the DME doesn't have to desperately add fuel trims to meet air/fuel commands.

Back when I first was testing the Fuel Scalar maps I concluded the maximum effective setting was 1.30, not the commonly-accepted level of 1.50. This was a blow to my Quest for Fuel ambitions and also the subject of some... uh... controversy. Because so many experienced hands told me my data seemed wrong -- and because that apparent 1.30 maximum represented bad news for any FrankenTurbo product -- I took another look at it.

In TunerPro I applied 1.50 Scalar values for a portion of the rev band, leaving the original 1.30 in place after 6000rpms. Here is the resulting fuel trims before/after:




The trims in the black lines clearly show the impact of raising the Scalar value from 1.30 to 1.50. Before the change, trims strayed into additive values. Now -- through that range from 4000rpm to 6000rpms -- the DME is breezing along with nice fat subtractive trims. Given the fuel system's data values at the 1.50 Scalar level the car's hardware & software clearly have big headroom for more airflow even on E85 fuel.

And I suppose we really ought to expect that. This car has over $1000 in fuel system upgrades. A higher-capacity in-tank fuel pump. A water methanol injection system. These things aren't cheap. And on the subject of "cheapness" we have had a bit of bad news to balance out the Fuel-Scalar-goodness: the simple and inexpensive nozzle configuration we're running is killing TMAP sensors. Here's another look at the very basic plumbing we've been running:




One really big nozzle placed in the aftermarket Throttle Pipe's included bung. Flowing at 800cc/minute we're talking about a fire hose-like blast of fluid. And doing that only a foot away from the TMAP sensor has proven to be unworkable. After killing two sensors in as many months, I have to say that convenient bung isn't a suitable location for the necessary WMI flows.

So the Throttle Pipe bung gets the new job of monitoring IATs...



...a smaller D05 nozzle gets placed further upstream, at the intercooler outlet...




...and a fresh TMAP gets installed. This time we're going with the 3.5bar-capable unit from the N20 engine.

Results on these adjustments next.

Thx



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matthewo matthewo is offline
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Default 07-30-2016, 07:28 PM

How about a true flex fuel system that can change fuel scaler, timing, and boost based on outputs from an ethanol sensor?

I am still not sure why nobody has done this yet, as the Vishnu piggy back could add / remove timing from a base back end flash dependent on map settings, they even tried this years back but it never really caught on or had any real support other then beta.

My only guess is the people who care that much just have pi and run straight e85 anyways
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Default 08-04-2016, 12:12 AM



The throttle pipe WMI bung can't serve as the sole source for injection, so we moved to alternatives. First, we pushed the injection point further upstream and reduced the flow from 700cc to 500cc. What we got for it was a drop in power. The 4200-6500rpm sweep performance suffered.




So the engine is happier with more WMI flow. Back in the day, I'd have been tempted to run a secondary nozzle pre-intercooler. But this time I chose to give the throttle pipe's bung a second chance with a much smaller, higher-atomizing #2 nozzle. This restores the 700cc flow the car was receiving originally, but in a more dispersed spray method. Logs before/after:




The data look pretty much the same. But the fueling corrections show the injectors are working less hard. And the car is faster:




So with the engine responding best to 700cc of WMI injected into an E85 fuel stream, I just couldn't get used to the idea that 15 of timing advance is all we could use. I had to take a second look at that. Who knows, maybe I'd get lucky again, as I did with the fueling scalar.

Logs before/after raising timing advance.




E85 backed up by WMI injection is a potent octane ****tail, so it's no surprise the knock sensors were fine with this change. And power came up a tad as well.




Time will tell for sure, but I'm leaning towards the idea this dual-nozzle configuration will supply the fuel I'm looking for. And it will do it without damaging anything downstream of the flow. This means I've reached a meaningful milepost in our great undertaking, the Quest for Fuel. And with fuel in ample supply, it's time we turn to raising airflows.

Up next: Doug at FrankenTurbo Takes an Unblinkered Look at Stage 1 Turbo Performance. (This next phase might very well end up better-titled as Doug at FrankenTurbo Inadvertently Helps Sell a Lot of his Competitors' Stage 1 Turbos; time will tell)



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Default 08-04-2016, 02:10 PM

Am i reading this right? You are running 20psi of boost with anywhere from 15-20 degrees of timing?? That just seems like a disaster waiting to happen.


2010 AW/BLK 135i VM 6465 Single Turbo, JB4 + MHD, VRSF CP & Tial, Big Tom, Fuel-It PI + Stage 3 + Return + Ethanol Sensor, BMW PE, MFactory LSD & Axles, Spec 3+ & MFactory SMFW, RB External PCV
Best stock turbo 12.5 @ 19.46 spinning all the way down
RIP 2008 AW/BL 135i
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Default 08-04-2016, 02:24 PM

Quote:
Originally Posted by BostonBeemah
Am i reading this right? You are running 20psi of boost with anywhere from 15-20 degrees of timing?? That just seems like a disaster waiting to happen.
I wonder if he added the timing on the dyno to find MBT???? Hmmm...


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Default 08-04-2016, 03:18 PM

Quote:
Originally Posted by dlp3719
Look Doug, (most) people are genuinely trying to help you.

When you refuse to provide the data (logs with wgdc and pwm), it makes you seems arrogant or at least stubborn with your head in the sand.

If you want to have a business on this platform, you are going to have to accept we are not going to be duped and have some very bright people on this platform.
+100000


If you want to convince the crowd here, you need to get a JB4, even if just to share the CSVs. I'll believe it when I see the CSVs to back up your data rather than screenshots and exported graphs.


--2009 BMW 135i--2016 Nissan Titan XD (Turbo Cummins ISV)--2016 VW Tiguan 2.0Tsi --1988 Beechcraft Bonanza--Suzuki GSX-R 1000--Honda CBR-600RR--

JB4 G5 ISO | MHD | E85 | Fuel-It S3 LPFP / PI | MFactory S3+ Clutch / SMFW / LSD / Mounts | Diff Lock | UUC Tranny Mounts | DwnPipes / Exhaust / FMIC | Chargepipe / Tial | KW V3s | HR Sways | HPA full M3 Suspension | BMS DCI / Oil Cooler Valve / Cowl Filters / 4bar / 2Step / OCC | RB PCV | Stri Gauges | Pole Position 225/265 | Installing: DR 6466ST
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boost junkie boost junkie is offline
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Default 08-07-2016, 08:20 AM

This thread is 2.5 years old and it's still just a bunch of useless "testing" posts. Meanwhile the other turbo builders are busy advancing the platform. This thread has been a colossal time waste.
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Default 08-07-2016, 08:26 AM

When you have absolutely nothing to offer a community keep them engaged with useless information until you do. Seems like it's working so far.


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weebles weebles is offline
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Default 08-07-2016, 10:10 PM

Quote:
Originally Posted by boost junkie
This thread is 2.5 years old and it's still just a bunch of useless "testing" posts. Meanwhile the other turbo builders are busy advancing the platform. This thread has been a colossal time waste.
I'm not too thrilled by this thread either but damn son, you're bad at math.
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Default 08-08-2016, 04:21 AM

Quote:
Originally Posted by BostonBeemah
Am i reading this right? You are running 20psi of boost with anywhere from 15-20 degrees of timing?? That just seems like a disaster waiting to happen.
There will be no response guys. This is a one way thread.


UK FBO 335i, GCs, JB4, PI meth, BMS CP, OCC, Braided brake lines. Diff Lockdown. TMAP sensor, custom bucketless stage2

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11.74@129mph on GCs, custom port meth injection.
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Default Stage 1 here we go! - 08-12-2016, 12:03 PM

So just what exactly are "Stage 1" turbos? Is their an official standard or specification? No. Until The Man puts in place an official registry of N54 Turbo Weights and Measures, the term "Stage 1" can be defined only loosely. And here is my recipe for it:

A 14T-fitment compressor wheel. But not just a plain-jane MHI 14T wheel, but a billet one with extended tips. Here's a prime example:



That 39.5/51mm dimension is a healthy improvement over the stock 35.6/46mm wheel. Plus it has an 11-blade configuration borrowed from Garrett with the added feature of extended tips, a BorgWarner design. So it's basically a Garrett/BorgWarner mashup. Seems pretty good. I'll take two, please.

What about the rotor? Well, the Stage 1 price point doesn't get you too far in that department. No upsized parts here. Instead what you get is a "clipped" rotor. Clipping is a favorite among turbo rebuilders. The theory goes that by removing some material from the underside of the rotor's blades, you improve flow capacity. To my mind, if the stock rotor's flow capacity needed improvement, the OEM would have simply fitted a different rotor. But clipping does have the advantage of being cheap to do. No machining of the turbine housing is necessary. And obviously there's no need for a brand new rotor shaft.

Turbine rotor clipping is defined in degrees. Typically you will see descriptions in the 5, 10 or even 15 range. But what does that actually mean? Well, for this test we'll be using "blade sweep" as our focus. Blade sweep is the angle of deflection between the blade root and the outside edge of the radius. Here is a CAD drawing illustrating that:




The stock rotors actually have a back-sweep as well. It is 12.




So the question was how much to clip? Every re-manufacturer out there who offers "Stage1" turbos has their own method. And I can't speak to exactly what they're doing. So I made the call to keep things conservative. We went with a modest clip that took the back-sweep angle from 12 to 17.









Before/after:




After machining the compressor housings to accept the larger compressor wheels, we reassembled the donor turbos.







The stock housings have a ~46mm OD compressor inlet, so the increase to a 39mm compressor inducer leaves "meat" to spare.




Next, it was time to put these bad-boys in the car!

OEM turbo left, Stage1-like-object on the right:




Prepping for EGT and backpressure monitoring:




Hello there, cute little guy!




The car is back up and running with shake-down testing going well. Test results on our E85/WMI fueling up next.


Doug Harper
FrankenTurbo


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Default 08-12-2016, 02:01 PM

Very cool pics and gif to match! Thanks for the info on clipping as Ive always been a little confused on the process. BTW That rear oil line looks kinked which may cause an oil backup in the turbo and smoking just as an FYI.


2010 AW/BLK 135i VM 6465 Single Turbo, JB4 + MHD, VRSF CP & Tial, Big Tom, Fuel-It PI + Stage 3 + Return + Ethanol Sensor, BMW PE, MFactory LSD & Axles, Spec 3+ & MFactory SMFW, RB External PCV
Best stock turbo 12.5 @ 19.46 spinning all the way down
RIP 2008 AW/BL 135i
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