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You boys that go and run this be careful in the colder weather with a MBC.
My subie used to overboost by 5-8 psi under 45 degrees....And when you wake up late for work and know its cold but don't know HOW cold it is you will be in for a surprise. That was the one thing that I hated about a MBC was that you had to re-adjust depending on air temp.
6psi on a car that is a hair over 2000lbs is going to be a riot to drive, just know the more boost you dial in requires better fuel and makes the margin for getting bad gas smaller.....AND that whole fuel economy thing sucks too....My wrx on the highway actually got better fuel economy after I did a stg4 setup then stock but I averaged around 12-14mpg around town. Boost is really really really addictive.
Did you go to the external gate to get away from boost creep?
You boys that go and run this be careful in the colder weather with a MBC.
My subie used to overboost by 5-8 psi under 45 degrees....And when you wake up late for work and know its cold but don't know HOW cold it is you will be in for a surprise. That was the one thing that I hated about a MBC was that you had to re-adjust depending on air temp.
So will a electronic boost controller prevent this from happening?
yeap, my car was just a money pit and I never got around to it. It ate the stock turbo, I went and got a used stg4....ate the vf30.....Bought the bad ass defi electronic gauges. Swapped in a usdm STi tranny, AND got a Ver 1 sti RA dccd controller hooked up to actually control the damn thing. I had a mbc so getting a electronic one was always the next thing I was going to do, until I broke something else or HAD to go faster then my buddies.
I would just bitch about the overboost then go and adjust it. But yes a electronic one would be ideal or get one of the MBC's that has super long lines that you can run into the cabin of your car, that way you can just dial it up or down depending on your needs at the time
I can't wait until this is released and I can afford it... I have some reading to do... i know VERY little about turbos.
__________________ Mods so far:
A Spec CAI
Rota Slipstreams 15x6.5 +40
XenithXenons 6000K Bi-Xenon
KBee Coilovers (Don't waste your money )
H-Fit Short Shifter
Skunk2 50mm Exhaust
WeaponR Street Header
I've been looking at a K20 swap seriously more recently in terms of the next step, but after some thinking and tinkering around in GT4(great game). I realized that a k20, despite more power, is going to bring a lot of torque steer and maybe a little to much extra weight in the front that might compromise handling balance.
When apply what seems to be somewhere around 160hp with little amounts of additional nose weight compared to the swap, the turbo option might be the perfect balance of power without sacrificing handling.
I know with more money you can make any car an overall performer, but this car lacks power and a decent amount of money is almost a guarenteed purchase for this car. That leaves little amounts of money to apply to improving the other characteristics of the car. I can't wait to whomp some @$$ at my local SCCA event if I go this route.
Hi Ben is it easy to re tune the e-manage for the A/T 1.4 idsi? can my mechanic who will be fixing the turbo do it for me? or do i need to get some kinda turbo expert? will this damage my CVT tranny?
__________________
EVIL Prevails when GOOD MEN DO NOTHING
You boys that go and run this be careful in the colder weather with a MBC.
My subie used to overboost by 5-8 psi under 45 degrees....And when you wake up late for work and know its cold but don't know HOW cold it is you will be in for a surprise. That was the one thing that I hated about a MBC was that you had to re-adjust depending on air temp.
6psi on a car that is a hair over 2000lbs is going to be a riot to drive, just know the more boost you dial in requires better fuel and makes the margin for getting bad gas smaller.....AND that whole fuel economy thing sucks too....My wrx on the highway actually got better fuel economy after I did a stg4 setup then stock but I averaged around 12-14mpg around town. Boost is really really really addictive.
Did you go to the external gate to get away from boost creep?
a proper MBC should not change boost levels. i have used Turbosmart and TurboXS MBC's with success in both cold and hot weather. boost levels stayed the same. External wastegate is the best way to regulate boost. Internal wastegates will start spiking when trying to raise boost levels.
this is where i also stress the importance of engine management. Emanage Ultimate (emanage blue does not have this option) has boost limiter cut in case the wastegate or boost controller malfunctions to prevent overboost. Like what Typerfit said, its the most important part of any boosted setup.
__________________ "Neg-rep'd by Claymore" Crew
03 DSM RSX Base Automatic-287whp/240wtq.....new build this summer
05 RS 1.0 TRD S/C tC - 283whp/200wtq 12psi + 35 dry shot
06 WDP TL A-Spec 07 VBP Fit Sport Auto-Totaled
07 WDP RDX w/ Technology Pkg
08 Vapor Metallic Saleen Mustang S281 3-Valve #25
08 Ford Expedition EL XLT
03DSM-RSX any MBC will be affected by ambient air temps. As air gets colder it gets much more dense, and that is what causes this problem. Again I'm not sure if down in houston you see the temps I did in the northeast section of the country but I can assure you that a MBC WILL SPIKE in the cold. It just happens.
All a MBC is is a bleeder valve off the wastegate, and at that level all it is seeing is air, not the volume of the air because of the temperature so while it may be set to 16 psi for a example you will spike at a much much greater rate, and a extrernal gate won't help because what is controlling it. Its not boost creep its a spike because of temperature. But I will agree with a part of what you said, a external gate is going to give you better boost control. BUT I had both the stock TD-04 turned up to about 16 psi and a vf 30 set to about 18 psi and neither ever had a hint of creep. The only issues I had was boost spikes in the colder weather. But I have seen turbo setups not hold the proper boost pressure because of that, I worked at nights at a audi shop that did performance work, we did a massive twin garret setup and those stock gates just couldn't hold at all...took forever to figure out where to fit external gates in a cramped S4 engine bay ( audis SUCK )
With a EBC you would be fine because of the solenoid that controls the whole setup detects the actual boost pressure and can adjust. My wrx and every guy I knew in the jersey region had the same issue because we all went to a MBC for the faster spooltime and the ability to not taper off boost in the higher gears like the stock setup did. Hell we almost saw a .5 sec dif with just that in the quarter mile.
But then again if I run a forced induction engine again I would run the same extra gauges again, exhaust gas temp, oil pressure and boost. I've seen a few subie engines die because of bad tuning or det that was caused by your exhaust gas temps going through the roof.
very good explaination, but again, you're dealing with those smaller turbos that cannot be easily controlled with a MBC. internally gated ones have such a tiny hole to for the exhaust to escape so it spools up to even more boost than desired. My cousin's WRX and my friend's 2.5L acted the same way when turning up boost, and we're talking about warmer temps in Houston. (btw, houston has ALL types of weather at any given time) Also, assuming the MBC is mounted in the engine bay, it should not see any ambient temps at all, but just normal underhood temps.
when turning up boost on those smaller turbos (even on external gated ones), they tend to spike. Boost spikes and creep is dependant on many variables. vacuum source, turbo size, WG type, etc etc. So we cant really dispute whether or not spikes/creeps are caused by MBC's. (As i've tried to remedy the boost spikes with Profec-2 EBC before, still spiked the same way) But we can just simply reduce the chance of it occuring by making sure we have the proper exhaust flow with least amount of backpressure. MBC's will work fine, but for extra insurance, better have the option of overboost protection in the engine management part.
EBC's are good, but you'll need to configure it just right if you want the boost-by-gear to work in your favor. There are a lot of adjustments, gains, variables, etc...But otherwise, just for increasing boost, its still a good option, just pricier.
As for gauges, i disagree with the EGT gauge part. It is not very useful compared to a wideband a/f gauge. (ie. AEM UEGO wideband) EGT's will vary all the time depending on setup and location of the probe. so you wont actually know the real-time a/f like the wideband offers. oil pressure and boost/vac gauge is a go! DO NOT GET THE CHEAP A/F gauge that taps off ecu line!!!
__________________ "Neg-rep'd by Claymore" Crew
03 DSM RSX Base Automatic-287whp/240wtq.....new build this summer
05 RS 1.0 TRD S/C tC - 283whp/200wtq 12psi + 35 dry shot
06 WDP TL A-Spec 07 VBP Fit Sport Auto-Totaled
07 WDP RDX w/ Technology Pkg
08 Vapor Metallic Saleen Mustang S281 3-Valve #25
08 Ford Expedition EL XLT
I have to agree a wideband A/F is ideal but the probes for that at least when I had my subie they were very steep on price compared to a EGT setup. And we knew where to put a egt on them, (cyclinder 3 as close as you can get...if I remember correctly) But then again the subie guys are a huge community cause we had thousands of guys messing with engine setups and other stuff like that so going with a EGT was easy for us....
AEM UEGO widebands can be had for $250shipped now That includes the gauge and Bosche wideband o2 sensor. scionlife.com has dealers that sell them for that price.
__________________ "Neg-rep'd by Claymore" Crew
03 DSM RSX Base Automatic-287whp/240wtq.....new build this summer
05 RS 1.0 TRD S/C tC - 283whp/200wtq 12psi + 35 dry shot
06 WDP TL A-Spec 07 VBP Fit Sport Auto-Totaled
07 WDP RDX w/ Technology Pkg
08 Vapor Metallic Saleen Mustang S281 3-Valve #25
08 Ford Expedition EL XLT
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Linear Mode
