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Good to know, I was wondering the same thing.

My only concern is our aluminum blocks and the extreme amount of heat the small turbo generates, largely due to the EGR and emissions regulations. I believe that's why the "overboost" is limited in duration by the factory tune.

Now if you can take care of that heat problem....
 

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Discussion Starter · #3 ·
Good to know, I was wondering the same thing.

My only concern is our aluminum blocks and the extreme amount of heat the small turbo generates, largely due to the EGR and emissions regulations. I believe that's why the "overboost" is limited in duration by the factory tune.

Now if you can take care of that heat problem....
I think part of my upgrade plan will be an intercooler and I'm also researching an oil cooler kit which I'd obviously have to piece together myself.
 

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Agreed if you do a tune I would definitely complement it with an aftermarket fmic... drop the air temp down. The bonus is your performance will go up another notch too. Win win :cool:
 

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Agreed if you do a tune I would definitely complement it with an aftermarket fmic... drop the air temp down. The bonus is your performance will go up another notch too. Win win :cool:
Eh not exactly. Typically with a quality intercooler, you'll lose a small amount of boost/power(1-3psi). It is however a tool much like forged internals that allow you to safely turn the wick up.
 

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Discussion Starter · #6 ·
Eh not exactly. Typically with a quality intercooler, you'll lose a small amount of boost/power(1-3psi). It is however a tool much like forged internals that allow you to safely turn the wick up.
Yep, this. An intercooler is very much a supporting mod not a direct go-fast mod.
 

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Agreed it should be thought of as supportive but will increase performance too if you have the ecu support. If you drop the air temperature you increase the air density without a tune you 'may' see a drop in power if the car ecu is still thinking at the same air to fuel ratios. Tuning changes these ratios but is limited to what is available (fuel in ie. Octane and air in ie. Flow density). Hence my comment to compliment your tune with an intercooler.. dropping the temp drops the pressure and increases the air density equals an increase of power and less risk of knock (detonation).

Check this out for a good intro on fmic's
The Thread to end all FMIC tech questions. Source: Bell Intercoolers FAQ
 

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How do the various tunes out there handle overboost? Does it hold the overboost level continuously or does it still peak the boost and then drop it off to a lower than reported power level?

Edit: Looks like a quick google answered my own question: overboost delete?
I like an overboost in low to mid range and then back the boost down (taper) as rpm rises. This keeps it fun (better drivability) while staying safe at the limit. This is especially important if you are playing with rev limiter settings.
 

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Surely the EGR valve closes and stops being an issue when you start to drive it harder? it only opens when you have been at a stable steady speed for a while
 

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Surely the EGR valve closes and stops being an issue when you start to drive it harder? it only opens when you have been at a stable steady speed for a while
Correct! The EGR does automatically close when a WOT (Wide Open Throttle) signal is detected from the APP (Accelerator Pedal Position) sensor.
 

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My latest tune REMOVED the overboost portion of the map, so as to not allow the engine to "run wild." Still need COBB to make the air intake kit--they just now added the FMIC! Already have a Turbo back COBB exhaust system, but that doesn't qualify for Stage II.
 
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