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Boosting 10 psi with mbc, Safe or not?

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  #11  
Old 11-07-2007, 11:22 PM
chaos92287's Avatar
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Default RE: Boosting 10 psi with mbc, Safe or not?

ORIGINAL: oneg

kemp traivs?
yeah thats him

ORIGINAL: Bogie

You should be fine as far as the motor goes running the K03 at 10 psi. I have a 2000 and it peaks at 9 and holds about 7-8 psig, so I would think 10 would be no prob. The only worries you might have would be a lean mixture at first - the fmic will cool the air better and you'll have more (dense) air into the engine - but the MAF should adjust the fuel mixture to compensate if it's working right? Also check your fmic setupfor a leak, which wouldalso contribute to loss of boost pressure. What MBC did you buy? I'm thinking about getting one untilI decide on a turbo and chiptoo.
it should. i just don't know how much the MAF can correct...anyone know?
 
  #12  
Old 11-08-2007, 12:23 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

the maf will correct a decent bit but i wouldn't push it. With a fmic i wouldn't go much above 10 becasue the car is still working off the fact that you have the less efficient side mount. so you don't want to throw to much at it.

When i was running 18lbs(had the diode mod and tunning) before i tuned it, it was at like 14.sumptin A/F ratio at open throttle. i had to add 112% to get my numbers down. I left it a little lean for a bit more power though
 
  #13  
Old 11-08-2007, 12:33 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

why would the car think he's running the stock sidemount? and how would that effect anything? the ecu learns and adapts to mods you put on by measuring everything
 
  #14  
Old 11-08-2007, 12:36 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

a fmic is goong to cool the air more and better, cooler air = more dense. Denser air on the same fuel settings makes it leaner
 
  #15  
Old 11-08-2007, 12:59 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

Why did the psi drop to 6 i thought it was around 8 stock?
 
  #16  
Old 11-08-2007, 01:04 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

ORIGINAL: Bondga

a fmic is goong to cool the air more and better, cooler air = more dense. Denser air on the same fuel settings makes it leaner
i thought denser air plus same fuel equals more power. the fmic is not adding or taking any air away so the a/f ratio would remain the same, right?

ORIGINAL: ocadam

Why did the psi drop to 6 i thought it was around 8 stock?
the air has to travel a longer distance so it loses some pressure on the way
 
  #17  
Old 11-08-2007, 01:20 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

I have a 2001.5 so this may be irelavant but on the cars that the diode mods works for you can run saftely 16 psi with a stock FPR. I have been running 15 psi for the past six months and lean codes or anything , and running strong.
 
  #18  
Old 11-08-2007, 02:21 AM
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Default RE: Boosting 10 psi with mbc, Safe or not?

ORIGINAL: chaos92287

ORIGINAL: Bondga

a fmic is goong to cool the air more and better, cooler air = more dense. Denser air on the same fuel settings makes it leaner
i thought denser air plus same fuel equals more power. Yes, sometimes, denser air +same fuel (underthe same psi)equals leaner mixture. leaner mixture(below the stoichiometric ratio 14.7:1)= more power. the fmic is not adding or taking any air away so the a/f ratio would remain the same, right? Right, If the air volume increases a lot in the fmic, the pressure and temperature drops a bit. Less psi = less boost. But it is denseronce it is cooled, and it takes more pressure topush (the samevolume of) cool dense air than hot expanded air. So thea/f ratio should remain aboutthe same, that's where the mbc comes in...

ORIGINAL: ocadam

Why did the psi drop to 6 i thought it was around 8 stock?
the air has to travel a longer distance so it loses some pressure on the way. +1 The pressure loss is due to the increased volume in the biggerFMIC and longer/wider tubes (longer distance = increased volume). It takes more effort from the turbo to compress a greater volume of air (fmic) than a smaller volume of air (stock intercooler) to the same pressure. That's why the MBC set to hold a higher psi will bring him back to stock of just over stock at 10 psig, while he also gets the cool, dense air, and a leaner mixture. The MAF should signal that more fuel is needed to maintain the safe a/f ratio and he won't be running lean,and will definitely see more power.
 
  #19  
Old 11-08-2007, 06:34 PM
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Default RE: Boosting 10 psi with mbc, Safe or not?

this is the mbc i used, it works pretty good for its price, the only thing is it doesnt bring boost past 10 psi and i was hoping to get around 14.

http://cgi.ebay.com/ebaymotors/VW-Je...spagenameZWDVW
 
  #20  
Old 11-08-2007, 06:53 PM
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Default RE: Boosting 10 psi with mbc, Safe or not?

The manifold is only seeing 6psi and now you are just filling in the drop from the fmic. The turbo is pushing more air, but the manifold pressure/volume of air is still the same. So everything is fine.

As for those forge and other 3 prong mbc, they are very limited on the amount of boost you can up it by. So not worth having imho. Just stick with a brand name company mbc and you will be fine.
 


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