[johnung]

Originally Posted by LiamLikesFruit

Nailed it! When it comes to volume, I was always told to upgrade to "bigger" needs to be dealt with by more volume to keep pressure up so you dont feel that minute lag. Referring to charge pipe, I was always told it's just so you can replace that plastic POS.

It's often important to know the history of how something developed. The original purpose often gets misconstrued over time.

Air to air intercoolers became very important when turbocharged engines began to be raced. Constant high revs around the track caused Intake Air Temperatures (IAT) to skyrocket. Intercoolers were developed, the bigger the better to lower temperatures to be able to race. Little to no concern was given to turbo lag because a high speed race track doesn't have conditions where turbo lag is evident like standing starts and low rev acceleration.

So intercooler manufacturers and track users were focused on IATs as the way to measure the effectiveness of a particular intercooler.

Later car manufacturers began to make turbocharged engines for street cars. It was a way to achieve better mileage and weight savings while still having the power of a much larger normally aspirated engine when you put your foot down.

A lot of research and development went into making those early turbo engines drivable on the street. People who were used to driving a big V-8 didn't want a turbo 6-cylinder if it meant putting the pedal down and counting to 2 or 3-Mississippi before the engine power came on. This was literally the case with a 1999 Volvo twin-turbo 6-cylinder that I owned.

So I developed a great personal hatred for turbo lag. The BMW N55 6-cylinder with its twin scroll turbo and low end sharp steep torque curve was a huge attraction to me.

Car manufacturers carefully choose the intercooler for its engine to make sure that it has adequate cooling to keep IATs down and the least amount of turbo lag possible for maximum drivability on the street.

But when car engines are modded to increase performance that sends a higher volume of even faster hot air to the stock intercooler. Eventually the stock intercooler is overwhelmed and the air coming out of it is just too hot for the engine.

The modded engine needs a higher capacity aftermarket intercooler. The problem is that there's no simple way to replicate the intercooler testing that BMW engineers did to determine the ideal intercooler for maximum cooling with the least turbo lag.

Intercoolers for track cars are chosen mostly by IATs which are simple to measure. But there is no easy way to measure turbo lag. Some intercooler manufacturers quote numbers and graphs of Intake Air Pressure drop or Intercooler flow through. Both of these should correlate to turbo lag. But most intercooler manufacturers don't discuss these things, presumably because their Intercoolers have very poor numbers.

The engineering philosophy is very simple, install an intercooler that's big enough and fast enough to keep IATs at bay, but small enough to increase turbo lag the least. It's trying to find a happy medium without an easy way to quantitatively measure turbo lag.

IATs are easy to measure so there's a tendency to choose the biggest baddest intercooler that drives IATs into the ground. But that isn't necessary. A smaller intercooler (maybe a little smaller or a lot smaller, who knows) that keeps IATs under control should also do the best job of controlling turbo lag. It would take time, money and equipment to duplicate the IC decision process of car manufacturers.

CHARGE PIPE issues for BMW center around the F30 N55 engine which has by far the most charge pipe failures. It's actually because the shape of the CP is poorly designed with a 90 degree turn at the throttle body end where it breaks. The plastic can't take the stress and vibration. It breaks on stock cars and is certain to break on tuned car.

But the history gets lost and the prevailing assumption is that plastic can't handle boost pressures and must be replaced with aluminum. And not just on the F-N55 but on all engines!

Charge Pipe manufacturers and retailers aren't going tell people that the risk of a plastic CP breaking on other engines is drastically lower. That would hurt business. The funny thing is that the Turbo to Intercooler (TIC) pipe on the N55 is under the same boost pressure and is also made of plastic. But it rarely fails because it is shorter and straight- so no 90 degree bend to weaken it.

But yeah I'd probably upgrade my CP and TIC even if I had another engine. Increased reliability, even if the stock plastic pipes have no where near as much risk as people assume.

Hope this helps!

[Info@mad-us.com]

Originally Posted by balcinzop

Looks like the ARM one as well, which I run.

The Arm is a single core, this is a stepped core.

Our core has also been upgraded since the last time this thread was updated . All MAD intercoolers now use high density cores for maximum cooling