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Old 04-19-2005, 10:32 AM   #1
fat angel
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Default 13.5 psi on stage 2.5?

i have lookded and can't find an answer. i have not been able to hit target boost with my 2.5 setup. it peeks at 13.5 consistently. i have all of the cobb requirements and a fmic, header, and fuel pump. anyone have any ideas? i have gone over the hoses so many times i cant count. help?
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Old 04-19-2005, 10:40 AM   #2
subieworx
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It could be that the added pressure loss due to the addition of the FMIC is causing your to not hit full boost. Have you called Cobb? They would be able to tell you what to do.
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Old 04-19-2005, 10:55 AM   #3
fat angel
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i've tried and they said for the most part to use the streettuner. i can make up for the pressure drop but i didnt know if that much of a drop would be normal.
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Old 04-19-2005, 10:58 AM   #4
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Most FMIC are dramatically larger than TMIC.
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Old 04-19-2005, 11:08 AM   #5
fat angel
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i know but is 3psi drop about normal for a fmic? i have an abc that i was planning on putting on to compensate for the pressure drop but thought that seemed like a little too much.

also just to clarify if i am only hitting 13.5 and target is 16.5 will the fuel still inject the amount for the 16.5?

Last edited by fat angel; 04-19-2005 at 11:16 AM.
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Old 04-19-2005, 12:52 PM   #6
hawker800mech
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Try playing with the size of the restrictor "pill" in the line going into the compressor side of the turbo. If you are using the stock pill, it may cause a lower boost as it did with me. You will have to go down in size, though. If you still have the lines from the VF3x, you can use very small wire gauge drill bits to increase the size of the hole in the pill from the VF3x turbo. When the size is too small, it will peak like a mad man, so be cautious.
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Old 04-23-2005, 07:16 PM   #7
anthonyrb98
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where can i get a pill smaller than the stock restrictor? i'm only seeing a peak of 15.7 lbs. on my cobb 2.5 w/ vf30
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Old 04-23-2005, 07:26 PM   #8
fat angel
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well i think part of the problem for mine was the egt sensor leaking in the aftermarket headers. just enough to make a difference. then i checked my boost using the ap and my gauge is off a little. so im a little shy of target. although i hit target yesterday at about 5k rpm in 4th. just for a second though. i still think im gonna hook the abc up and make 26.5 at 4.5k .
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Old 04-23-2005, 10:48 PM   #9
hawker800mech
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Quote:
Originally Posted by anthonyrb98
where can i get a pill smaller than the stock restrictor? i'm only seeing a peak of 15.7 lbs. on my cobb 2.5 w/ vf30
The pill that came with your VF turbo is smaller. If you lost it or never had one, you could make one. Just get some brass stock, cut to size, dress the ends so they are not sharp and will easily go into the hose, and drill the holes of various sizes to tune with. It's better to start with the stock size and work your way down in size. That is so you don't get big boost spikes with too small a restrictor. You can get brass stock from www.mcmaster.com.
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Old 04-24-2005, 04:23 PM   #10
WolfInSheepsCLothing
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cobbs webiste says:

Map Name: VF34 91 oct
Description: VF34 map using 91 octane fuel. Requires VF34 turbo, STI injectors, stock intake, stock intercooler and turboback exhaust. 315HP / 295 ft-lbs.

why are you expecting to hit boost of 16's with a map designed for the stock intercooler? FMIC would need a custom tune, right?
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Old 04-24-2005, 04:29 PM   #11
hondaeater69
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I couldn't imagine the lag on your set up. Generic tune, with headers AND a FMIC with a vf34. . . . skip the BC and go get a tune, you REALLY need one, those two mods are OUTSIDE the learning of the ECU.
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Old 04-24-2005, 04:54 PM   #12
fat angel
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it's not that bad. i love the car like this. iam going to get a real tune once the protuner makes it this way. i have been hitting 16.5 sometimes 17 pretty much all the time now. must have been the leak. the lag has been reduced dramatically by wrapping the turbo and headers so it's not bad like i said. and although the fmic would be more beneficial with a custom map it's not going to really hurt me now. for what i got it all for i can deal with the lag till i get a custom map. i didnt plan on getting all those parts that quick it just kinda happened out of the blue. i had it all on before i hit a 1k miles. if i had planned on it i would have never went with the ap. i think the thing is trash. but hopefully the protuner might change my mind. its the only thing keeping me from getting a utec.

Last edited by fat angel; 04-24-2005 at 05:23 PM.
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Old 04-24-2005, 05:07 PM   #13
fat angel
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by the way hondaeater did you ever get the streettuner to work on a tune for you?
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