The V6 Mustang has come a long way with the S197 platform – from being a lowly also ran to becoming a car that produces more horsepower than the Mustang GT of just 10 years ago. Although we’re V8 fans, without the V6 to provide the bulk of sales, there would likely be no Mustang at all.
With the 3.7-liter being the best V6 engine ever installed in the Mustang, many enthusiasts are finding they respond well to the same approach as their V8 brethren. To find out what we could do with a new 2013 V6 ‘Stang, we turned to BBK Performance for a few popular upgrades. We spoke with BBK’s Tim Gilpin about the growing trend of V6 Mustang performance, “BBK saw big potential in the V6 engines and when R&D started testing the new headers designs, throttle bodies and cold airs, we were amazed at the results.”
We’re going to start by installing a set of BBK headers, and matching catted X-pipe. We’ll then proceed to install a new BBK throttle body and cold air intake. Along the way we’ll perform dyno testing in between the exhaust and induction modifications to document the gains found with each.
Long Tube Headers
BBK saw big potential in the V6 engines and when R&D started testing the new headers designs, throttle bodies and cold airs, we were amazed at the results. -Tim Gilpin, BBK Performance
Just like the 5.0, the 3.7 V6 responds well to exhaust modifications, on an adjusted power scale. What we mean is that we’ve seen Coyote powered Mustangs pick up between 15-20 hp with long tubes installed, which is around a 4 percent increase, so we will be looking at a fairly relative percentage increase on the V6.
Letting the engine breathe better on the exhaust side can dramatically improve the engine’s performance. Long tube headers improve exhaust flow and thus power production. Opening the exhaust side up together with the induction side allows for larger volumes of air to be moved through the engine in a more efficient manner. It should also give us a broader spread of horsepower, improving not only the car’s peak dyno numbers but power under the curve, where the engine spends most of its time.
BBK builds their V6 long tube headers for the 3.7 from the same materials that their V8 headers are made from. For our 2013 V6 Mustang, we’re installing BBK Silver Ceramic Coated long tube headers part number 16420. These headers feature 1.75-inch CNC mandrel-bent primary tubes and 2.75-inch collectors. They also have 3/8-inch thick flanges for improved strength and durability. We chose the Silver Ceramic Coated headers because they’ll maintain their appearance better, as Gilpin tells us, “Our polished Silver ceramic finish keeps its finish and lasts a very long time verses the chrome that will change color very quickly – the silver ceramic also dissipates the heat better.”
The use of long tube headers also requires the use of a matching X-pipe on our V6 Mustang. This car is a daily driver and we also want to keep it semi-emissions compliant. To meet both of these criteria BBK sent us their catted X-pipe, part number 1461. The pipe is CNC mandrel bent and comes in 2.75-inch diameter to match our long tube headers. This is the same exhaust diameter as the stock Mustang GT.
The X-shaped crossover section of the pipe improves exhaust flow and scavenging by equalizing exhaust pulses, it also gives the exhaust note a more aggressive tone. “X-pipes flow better at high RPM in most applications,” says Gilpin. With the long tube headers in place installing the catted X-pipe is easier than replacing the factory original, since the long tube headers allow the new X-pipe to simply fit between the collectors and the after-cat exhaust tubes.
The catalytic converters utilize high flow steel substrates, that according to Gilpin should outflow the stock converters, and provide long life. Unfortunately at this time BBK does not offer a California CARB approved catted X-pipe for this application since long tubes in all forms are illegal in California. This is due to the tight restrictions California places on emissions control devices. Gilpin explains, “California requires very different catalytic converters to meet CARB standards and the ones we have tested are somewhat restrictive and extremely cost prohibitive at this time, this may change in the future.”
Test Part 1: Exhaust
We wanted to find out how much power we gained with each modification made. So first we baselined our 2013 Mustang V6 on our in-house Dynojet. Completely stock, the car spun the rollers to 219.8 hp at 6,500 rpm, and 198.8 ft-lbs of torque.
With our exhaust modifications completed we again strapped the car back down on the dyno, and spun the rollers. For this first round of modifications our peak numbers came in at 223.9 hp and 197.2 ft-lbs torque. As we mentioned before though, peak numbers don’t always tell the entire story. Comparing the dyno graphs look at how much more power the engine makes earlier in the curve. Also compare the torque, and notice how the torque peak has not only moved up higher in the RPM band, but also comes in earlier. This is where the headers are making the most difference, rather than just in the overall peak horsepower and torque numbers. This type of power gain within the lower RPM range is power the engine can use to accelerate the car faster, rather than simply a peak number that comes on quickly near redline.
Part 2: Induction
With the exhaust system taken care of, we turned our attention to the car’s induction side. First we installed a BBK power plus throttle body, part number 1822. This throttle body is CNC machined from 356 aluminum. It’s also the same high performance throttle body that BBK sells for 5.0 Coyote powered Mustangs.
When electronically controlled throttle bodies replaced the old cable actuated throttle bodies in 2005 there was concern over the electronics involved. A drive-by-wire throttle body has no mechanical connection to the accelerator pedal. This means that with a replacement throttle body an enthusiast must either transfer the electronics from their original throttle body assembly, or purchase one with electronics installed.
BBK uses OEM style electronics on their throttle bodies to eliminate the hassle of transferring the electronics. This literally makes the throttle body a bolt-on installation, requiring that the original simply be removed from the engine, disconnected from the electronics and swapped directly for the new BBK unit. There’s no transferring of electronic motors or sensors, and no special calibrations to perform. Measuring 85 mm in diameter the BBK throttle body is substantially larger than the original equipment Ford part.
Cold Air Induction
Completing the picture for our induction side is a BBK cold air intake system, part number 17785. This system replaces the factory air intake tubing to provide a cooler, denser air charge, as well as a smoother path for the incoming air to follow.
The cold air intake is designed to work with the stock computer calibration requiring no additional tuning. BBK achieves this by using a CNC machined integral mass air flow sensor housing in the air intake system. This MAF housing is designed for OEM calibration, making a mandatory tune unnecessary, though BBK does state that further benefits may be realized from a tune optimized for cold air induction.
Also included in this system is an air dam to block engine heat, which seals against the hood and sides of the engine compartment, and a BBK conical air filter.
Installation of the BBK cold air intake system is also a straight-forward bolt-on operation, made even easier by the fact that we have already removed much of the stock air induction system to gain access for our throttle body replacement.
The Complete Package
Spinning the Dynojet rollers once again we saw significant gains in both horsepower and torque, with the 3.7 V6, turning in 230.0 hp, and 204.0 ft-lbs, an additional increase of 6.2 hp, and 6.8 ft-lbs to the rear tires. Peak horsepower pulled through 6,750 this time, and torque moved up the scale again not dropping off until after 5,800 rpm. Though, under the curve, we picked up an average of 9.3 hp and 8.2 ft-lbs. We would also note that the throttle body is probably not effecting the power increase with the level of modifications we currently have installed. Once we strap on a power adder, the less restriction from the BBK throttle body will be apparent in making more power over the OEM counterpart.
Power under the curve, before the peak was also affected again. The engine made near peak horsepower from 5,800 rpm climbing slowly for the net 1,000 rpm. That type of flat power means that in the upper RPM band the engine is pulling hard, something that should be noticeable on hard acceleration.
Breaking Down The Numbers
While we didn’t see massive gains in power, we have improved the performance of this V6 Mustang significantly throughout the RPM band without sacrificing low-end power or drivability. Above 4,200 rpm the gains become apparent on the dyno graph. With power steadily climbing and staying above the stock numbers. The engine’s torque-band is broader, and the engine now produces torque for a longer section of the RPM range. In fact it isn’t until 6,300 rpm that torque of our modified car drops off to match the stock engine’s torque of 198 ft-lbs at 5,600 rpm.
These modifications open the door as well for future changes to this engine. A tune optimized for these modifications will likely yield more power. If we choose to run forced induction in the future, or make other modifications to the engine the induction and exhaust sides are now adequately equipped to handle such modifications.
The V6 Mustang offers a reasonable alternative to those who need fuel economy, and a more budget minded daily driver, or who can’t afford the expense of a Mustang GT. With performance companies like BBK taking notice of the number of enthusiasts driving these cars, we expect to see great things coming from V6 Mustangs for years to come.