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Zax Bugeye "Shaggin' wagon" Build thread

140K views 548 replies 52 participants last post by  Liquidussnake 
#1 ·







Mods:

Engine Modifications:
Grimmspeed ceramic-coated Uppipe
Cobb catted downpipe (heat wrapped)
Cobb catback exhaust
Perrin Lightweight Crank Pulley
Ebay Oil Catch Can
Heat-wrapped headers
Tactrix OP2.0 Tuned by Zax with Mattypants handholding :giggity:
Pitch Stop Mount
STi Oil pan and baffle*
KillerB Ultimate Oil Pickup*
Grimmspeed EBCS
Grimmspeed MBC Hybrid boost control set to 21 PSI peak
Injector Dynamics 1000cc Injectors
Walbro 255lph fuel pump
Blouch TD05H-18G (40lb/min Turbo)
AEM Dry-flow filter and Corksport 73mm BigMAF
AEM UEGO WBO2 Sensor
PTP Turbo Blanket
BPM Top Mount Intercooler
TXS 50/50 Hybrid BOV/BPV
Perrin 4-2-1 ELH
GT Spec Splitter
Grimmspeed 3mm Phenolic spacers
Grimmspeed TGV Deletes
Gates Timing Belt Kit & Water pump
Mishimoto aluminum 2-core replacement radiator
Samco turbo inlet

Suspension/Steering Modifications:
Perrin 22mm FSB (stiff setting)
Perrin 22mm RSB (middle setting)
Perrin Endlinks
Perrin Stout Mounts
TIC Clunk-killer kit
TIC Rear Diff lockdown bolts
Whiteline Steering Rack bushings
Ebay STi (knockoff) front and rear strut tower bars
Custom Alignment -- -1.1 deg front camber, 0 toe, stock caster, -1.05 deg rear camber

Transmission Modifications:
Perrin shifter bushings
Subaru OEM Short Shifter
Group-N Transmission Mount
IXIZ concept clutch-stop

Wheel/Brake Modifications:
OZ Ultraleggera 17x8 +48 wheels (Summer wheels)
Rota GR-A 17x7.5 +48 wheels (Winter wheels)
Hankook Ventus V12 Evo 225/45/17 tires (Summer)
Bridgestone Blizzak LM60 225/45/17 tires (Winter)
Stoptech SS brake lines (front and rear)
Speed Bleeders
Motul RBF600 fluid
Prodrive 330mm Brake Calipers & Rotors (front)
H6 rear rotor upgrade painted silver to match the fronts
Flapatax mudflaps (Hate away MFers)

Interior
Subaru Ti shift knob
Pioneer AVIC F700BT HU
Ultra-wide rearview mirror (life-saver in MD traffic)
Cobra something-or-other radar detector w/ gps hardwired
ATI Clock Gaugepod
AEM UEGO Digital AFV gauge
Prosport Oil Pressure gauge
Prosport Oil Temperature gauge


Future Plans
2015 WRX FA20 Goodness :)
My fluids:
Engine Oil - GC (German Castrol) 0w-30
Tranny Oil - Subaru Extra-S
Brake Fluid - Motul RBF-600
Rear Diff Fluid - Motul diff fluid
Coolant - Prestone Yellow + Redline WaterWetter + Subaru Coolant Conditioner
Power steering - Subaru OEM
 
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#277 ·
Interesting find. Unexpected at least.
 
#281 ·
Got around to scaling my MAFv last night. Results were less than stellar. It seems that the Fujita Intake may have a significant amount of turbulence right around 2.25V or approx. 25 g/s... this is especially unfortunate since that is the typical cruise airflow and likely responsible for my large variation in LTFT over a short period of time.



On another note, looks like the pulls at only WG pressure (9PSI) are around 270g/s airflow. Since I will be looking to target 20-21PSI, it is likely that my stock MAF sensor will peg (300g/s max). Fortunately, the MAF hack allows 16-bit ECU guys to increase the theoretical airflow maximum to 600 g/s. I'm currently writing this into my map. Since I'm on the stock-diameter MAF housing, I will still be limited to 352 g/s.
 
#285 ·
So aside from replacement, is there anything you can do about the MAF turbulence? The Banish book mentioned extra mesh screens (in addition to the OEM one) could help without significant flow restriction. You could also go to Speed Density, I guess...
 
#286 ·
A little turbulence is normal. I won't jump to this conclusion just yet. The MAF and fueling system does funny things when the scale is very far off (>8-10%).

FWIW, I'm going to start performing CL MAFv scaling, which should really focus in that 15-30g/s airflow range:
http://forums.nasioc.com/forums/showthread.php?t=1427448
 
#287 ·
You can see the affect the Fujita intake had on my LTFT:

With stock airbox, injectors scaled:


With Fujita CAI installed, injectors same scale:


LTFT ranges are -14.99 to 14.99, so you can see column C is pegged and relying on STFT to bring the mixture to stoich for CL.
 
#288 ·
Plot your AFR errors over RPM at various loads. I bet you'll find it's RPM dependent and not MAFv. Fuel system resonance ftl.

Never know... That's just at weird place to have such a sharp spike.
 
#289 ·
I thought about fluid resonance in the rails. I might go back to the stock airbox to see if the same issue is present.
 
#293 ·
Given the fact that my MAFv peaked at 4.6 volts during my untuned run, I made the decision to move to a 73mm MAF housing, which I purchased off NASIOC.
 
#294 ·
Well the 73mm MAF housing and enormous ridiculous filter is installed!



Because the diameter of the new MAF housing is 73mm while the stock is 65mm, the new housing has (75^2)/(65^2) = 1.26x more crossectional area. As such, I scaled the MAF sensor by 126% to account for the slower intake velocity per relative air mass. This was a rough approximation since there are other factors involved in the actual MAFv scaling (turbulence, fluid dynamics, etc.). I tell you guys and gals, as an engineer by profession and a physicist by education, I have NEVER seen a rough calculation prove so accurate in the world off-paper:



Game on.
 
#297 ·
Holy crap zach - I am shocked that is as close as well. Awesome.
 
#300 · (Edited)
Compression test results:

Cylinder 1:


Cylinder 3:


Cylinder 2:


Cylinder 4:


Motor was only lukewarm, unfortunately. Compression in cylinder 1 dropped a few PSI, but still well within healthy limits. Still excellent compression for a 2003.

149 - 155 - 157 - 152
 
#301 ·
Alright, I suppose I should give an update!

I had a local shop perform a full leakdown on the motor and vac leak check. The leakdown results were excellent, with less than 4% loss in each cylinder. The Vac leak check was not so great. Evidently I had vac leaks in hoses, from the TGV-cyl head gaskets, TMIC-TB silicone coupler and a few others. Furthermore, like I suspected, injector 3 was poorly seated in the fuel rail. At least I now know from where the issues arose. Furthermore, I'm excited to hear that my motor is in excellent condition. Since I mentioned I had checked injector #3, I will tell the embarrassing story to anyone who wishes to know via PM.
 
#305 ·
Matthew already knows the story, and the rest of you I'll tell over pillow-talk :D

Anyway, car is back. Vac leaks have all been addressed.
 
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