PRL's FL5 Intercooler Testing: Tube-and-Fin vs. Bar-and-Plate vs. OEM

Our Testing

For our FL5 intercooler testing, we conducted a controlled, same-day comparison between the OEM intercooler, our existing PRL bar-and-plate intercooler, and our new PRL tube-and-fin intercooler. Ambient temperatures remained steady in the mid-70s°F.

Testing focused on how each intercooler behaves under continuous, high-load conditions; specifically, how quickly they heat soak and how they recover.

Testing Methodology

To ensure consistency, each intercooler was tested under identical conditions:

• Multiple 4th-gear dyno pulls were performed back-to-back.

• No cool-down periods were allowed, intentionally pushing each unit to its maximum heat-soak point.

• Cold-side charge temperatures were used to determine when heat soak was reached.

• A high-power dyno fan supplied consistent airflow for every test.

This setup simulates demanding scenarios like long track sessions. Real-world track driving will typically offer better thermal recovery due to braking zones and higher vehicle speeds, but for comparison purposes, this same-day, same-conditions approach offers accurate, repeatable data. At-speed temperatures will vary, but the comparative results remain representative.

Figure 1: Charge-Air Temperature Comparison

OEM Intercooler (Green Line)

The OEM intercooler is already heat-soaked on the very first pull, starting at 136°F. Temperatures increase rapidly, rising into the 200°F range, and eventually peak at 220°F under maximum heat soak. This demonstrates the limited thermal capacity and cooling efficiency of the stock unit during repeated high-load use.

PRL Bar-and-Plate Intercooler (Orange Line)

Our bar-and-plate intercooler begins at 86°F, showing minimal temperature rise during the first two pulls, only slightly exceeding 100°F on pull two. This makes it excellent for drag racing and street driving where short bursts of load are common.
However, with each additional pull, temperatures increase by roughly 10°F until stabilizing around 190°F as the unit’s thermal mass becomes saturated.

PRL Tube-and-Fin Intercooler (Blue Line)

Early pulls resemble the bar-and-plate unit, though temperatures sit 5–10°F higher initially. This is due to the tube-and-fin’s lighter construction and reduced thermal mass.
As testing continues, however, its efficiency begins to shine. Later runs stabilize between 160–170°F, indicating superior performance during sustained high-airflow scenarios like track sessions or extended spirited driving.

Figure 2: Performance Overlay – Understanding Advantage Zones

Figure 2 overlays all intercooler results, highlighting performance “zones.”

• In the orange zone, the bar-and-plate unit maintains a slight early advantage due to its greater thermal mass, acting as a thermal “battery” that absorbs heat.

• As the test progresses, the tube-and-fin design surpasses the bar-and-plate, demonstrating more efficient heat transfer under continuous load.

It’s important to note that the tube-and-fin intercooler is 8 pounds lighter than the bar-and-plate. The fact that it remains this competitive early on, despite having significantly less thermal mass, is very impressive.

Figure 3: Tube-and-Fin Core Construction

Figure 3 shows a cross-section of our tube-and-fin core.

Each oval represents a tube within the heat exchanger, secured in place by the surrounding end plate. These tubes feature much thinner cross-sections compared to the bars inside a bar-and-plate core. This allows:

• Reduced weight

• Faster heat transfer

• Higher cooling efficiency

This lightweight, efficient structure is what enables the tube-and-fin intercooler to excel during longer sessions where sustained airflow is available.

The data makes it clear. If your driving demands consistent cooling over long sessions, the tube-and-fin intercooler is the most stable, efficient option in our lineup.