Impact of an intercooler only on stock EcoBoost engines -- COBB's Well Documented Testing

[Lion77]

The aftermarket IC's are Bar and Plate vs. Tube and Fin. Tube and fin are lighter and tend to flow better at a given size, but require expensive machinery to manufacture on a mass scale. Tooling setup-cost is high with tube and fin, but manufacturing cost is low on a mass scale both from materials and labor, so that is why OE's use tube and fin.

Bar and plate are generally manufactured manually, they are heavier and don't flow as efficiently BUT add thermal mass. And you can achieve the same flow rates by using larger cores to compensate, so that's actually why all the aftermarket bar and plate intercoolers have much larger core volumes than the stock tube and fin units, they need the larger volumes to achieve the same flow rates and pressure drops as the tube and fin units.

The advantage comes in the much higher thermal mass and resulting increase in surface area both of which increase cooling performance at the expense of cost, weight and size, which off sets their deficiencies in flow per a given volume. Turbos can compensate for added heat by increasing boost, in fact the Ford PCM tuning targets air density, not boost pressure.

It will increase boost pressure (to within operating limits of the turbos) as the IC heats up to achieve the targeted air density at a given load. The downside is that increasing boost pressure also increases heat and back pressure on the exhaust side, so as boost pressure increases, it drives the turbos further out of their efficiency island (thus increasing exhaust back pressure and turbo heat loading), so you can only increase boost to compensate for heat to a limited degree.

If you can achieve 30~40F cooler charge temps at the same pressure drop with an aftermarket IC, you're reducing the load on the turbos because they don't need to be driven as hard to achieve the target air density. This will lower heat and back pressure, allowing for making power more consistently and efficiently.

This really only matters at sustained high load. For short bursts of power or typical uses, it's not relevant and the factor IC is quite optimal for those applications. But for 1/4-mile passes, hot lapping, racing or any sustained WOT you will see benefits of an IC upgrade, especially in hot weather where the differences are most noticeable.

OE's don't use bar and plate because of cost, both in materials and manufacturing labor. They are much more expensive to manufacture as it's still largely a manual welding process and require much more material per a unit to produce, but if your after performance and durability, bar and plate is worth the cost and weight. Also the added mass acts like a thermal flywheel, creating a lag that helps maintain stable charge temps during very high load transients.

The downside is that when bar and plate do heat soak, they take longer to cool off due to the mass, but generally, they are MUCH harder to actually get to the point of heat soak AND the added surface area tends to off-set most of the added mass to the point that they seem to actually cool off about as fast as tube and fin in practice under real-world driving.

There's a lot of here say and theory on this or that, but in practice, generally larger sized bar and plate IC's tend to significantly outperform OE tube and fin intercoolers due the combination of overall properties.

Is it worth the extra cost and ~15 lbs more than stock? Depends on your use cases.

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[Lion77]

Also, BTW, pressure drop in an IC isn't always a case of "lower is always better", because if the air isn't transferring enough thermal energy via contact surface area and dwell time, you can have an IC that flows better (lower pressure drop) but provides inferior cooling, so you're at an actual net negative benefit!

 

[Lion77]

Hey Lion, have you made a decision on what IC you’re gonna go with? I’m in FL and temps are fine but we are about to turn the corner and hit spring which can just be summer…

I ended up ordering a CP-E Delta core. I think the engineering and design is more optimized in their stuff than 99% of the other units. They put some CFD (Computational Fluid Dynamics) modeling into their designs to minimize turbulence and even out flow throughout the core with internal diverters, so you don't need as large of the core to get the same cooling.

They also stated they have higher fin density that most of the other cores on the market = more surface area. End tanks are cast like most higher quality units, but the fin density, flow diverters and CFD optimizations all add up to a higher efficiency core with similar pressure drop to stock. What does that really mean?

1. Allows them to use a smaller core that performs the same as slightly larger cores due to better overall efficiency = maintains factory-like drivability (aka lag caused by too much volume) and fitment without modification.

2. MAY help, in theory, with better air mixing on the outlets since you don't get any "hot pockets" of air going into a single cylinder, at the very least, the air temp at the outlet should be homogenous = ideal.

3. With slightly lower thermal mass, if you manage to heat soak it (all IC's will heat soak for example when sitting in traffic or at a drag strip), it should allow for more rapid cooldown = better overall performance with dynamic throttle use.

4. Smaller core should be lighter in weight than comparable units, I BELIEVE the Delta core for the 3.0L in the BR / RR is 16 lbs, not bad and not enought to make any noticeable difference in handling.

They do allow you keep the factory IGS too, does not affect radar cruise or require special brackets, but I'm not 100% sure if you can still keep the rear passive shutters. If I had to sacrifice shutters, it would be the back shutters for low-speed uses as I think the front grill shutters are more important for cold start wear and my truck gets driven year around!

Also note none of the regular rangers have rear shutters, only front, but I THINK the CP-E will allow both to be used like the Wagner (I'll report back when mine arrives, having it powder coated black as I like the stealth look so it's a few weeks out and who knows when I'll have time to install).

In the Bronco's, install was only 30 minutes! They did not have to take out any factory ducting, just pull the skid plate, remove tow hook bolts (which also hold the IC in), swap over the rubber isolator grommets, disconnect the charge pipes and swap the ICS, bolt it back up. No cutting, no changing brackets etc. and they market it as the same fitment for the RR.

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