installed a bigger intercooler, but completely lost low end torque?
 

as the title stated, one of my buddy installed a bigger intercooler then the OEM one, but i have no idea how BIGGER it is. but after installed, all the low end torque had been completely lost.

anyone got any idea or any reason why?

the car is 2012 MB W204 C250 1.8L turbo.

I guess it can happen as more air is now required to compress into that area, which was smaller before, but that should just be part of the turbo lag I would think. Unless he have an air leak.

-Butt dyno needs to be recalibrated?
-Stock IC already efficiently sized for stock turbo
-New aftermarket IC shittier (flow wise) vs stock IC
-Boost leak
-Boost lag due to larger IC, ?additional piping

Check data logs with stock IC vs aftermarket IC. Otherwise you're just guessing.

If you install a bigger IC you increase the volume of air between the turbo and the intake manifold. Realistically you want the smallest one that gives you acceptable intake temps to keep the lag to a minimum.

I'm guessing your friend hasn't changed anything else on the car?

Sounds like a boost leak...

Why did he "upgrade" the intercooler?

Berz out.

You are losing pressure because of the intercooler. You now need more air pressure flowing through to make up for the difference. An intercooler upgrade should happen after basic bolt-ons have been added. Even then it may not be needed.

But a big ass intercooler looks siiiiiiiccccckkkkk!!!


:okay:

True story.

Your loosing boost through the larger intercooler. Turn up the boost to compensate.
:fullofwin:

Yup.
I bigger IC will take more air to fill before beginning to build the pressure that is boost.

OP, think about the extra volume of air that is needed to fill the new IC, including any piping, etc. If the same turbo is working to fill that space, it will have to work harder to build the same amount of power. Let alone, to build more power.

Also, IC doesn't make power. It is a support part that allows you to run a larger volume of air.

Chances are the car would run like shit if there was a boost leak. Especially with the closed system and multiple German sensors looking for that sort of thing.

He put an IC to large for his setup and is now seeing a pressure drop greater than the stock system over his OE intercooler.

In other words, he spent more money on a part he did not need to make his car slower and less efficient OR excuse to up the boost and put a new turbo in there to make the IC efficient for said performance.

Torque from 1.8L ? J/k
Like mentioned above, this is not Nitro Nation where adding parts equals gainz.
Also check for loose clamps etc... For leaks in air intake system

Sounds like the muffler bearings weren't torqued to spec...

Like everyone else on here has said, adding an inter cooler to a stock system is not always advisable, especially in our climate. If you're running stock intake, exhaust, ECU, boost pressure etc there's no reason for a larger FMIC. Bits very common for larger intercoolers and piping to effectively drop you're boost pressure in a sense.

With my focus st (2.0L turbo) I am running stock intercooler and piping for it still. I've done a few bolt ons like cat less downpipe, intake, Cobb tunes etc. I'm running a stage 2 91 octane tune and about 22.5psi boost pressure (15psi stock). They recommend I have a larger intercooler for the setup, but while watching post-intercooler air temps there isn't a need for it as of right now. Driving around its just like 75 degrees. A full boost under load pull sees it jump to maybe 95 degrees. But even in the summer it didn't go over 100 really. If this was a Californian climate then it would be a whole different ball game.

thanks for all the response. i will tell him to look for the leakage first.

No, there is no leak. If there was, the car would drive like shit.
Problem is that he needs to move a lot more air before building boost due to the larger IC.

His loss of tourque is boost lag.

Yeah, he has no leak. If he did there would be next to no power and a lot of noise from under the hood.

Switch back to stock IC.

Blow through a stir-stick, then blow through a bbt straw.

Which one has more pressure on the other end?

Personal favourite is to use soapy water and blow bubbles with a regular straw, bbt straw and then through a paper towel tube and see how big the bubbles are.

No.

Just no.

If there's a leak, it's simply a coincidence and would still be too small to be detected by the sensors in a closed loop system. The larger intercooler IS THE PROBLEM.

Period.

oh its a boost leak?,okay.
http://i3.kym-cdn.com/photos/images/...40/811/e45.png

Should have started with stickers :P

All your guys analogies suck. Think about how long it takes to blow up your blowup doll (stock intercooler) to a firm level(boost pressure). Then compare that to your blowup pool(large intercooler) in your parents backyard to the same firmness(once again, boost pressure). That lack of breath your feeling in your lungs(turbo)? That's called boost lag. What your friend is experiencing during his lack of torque.

Until you get a lung transplant, or start running marathons your big pool is going to take so freaking long to blow up and have fun, you might as well stick to your blowup doll.

Retarded analogy but I think anyone can make sense of it. Ha

So much fucking win.