In the past there have been many heated discussions here and on other Mustang forums on if long tube headers on a 3V S197 actually give any significant gains over a good X pipe and better flowing cats while keeping the stock manifolds in a NA car. Some have said that the exhaust side of the head doesn't flow well enough to justify headers on a NA car compared to high flow cats and an X pipe.
The 2005 Mustang GT I bought came with a Bassani X pipe and aftermarket cats. I was interested in getting baseline numbers before I started modifying the car. I took the car to a Performance Specialties, Inc. in Pottstown, PA and dynoed the car. It produced 329 HP and 312 ft-lbs of torque. Power modifications on the car are:
C&L racer intake
Bassani X-pipe
SLP Loudmouth axle back
CMCV delete plates
Comp Cams NSR cams
Steeda underdrive pullies
SCT Xcal3 tuner with a Bama 93 octane tune
About a week and a half ago, I installed the Kooks headers with cats and X pipe. Then I took the car back to the same shop to have it dynoed again. The results were 347 HP and 320 ft-lbs of torque. Weather conditions for both days were similar. It was 80 degrees with 46% humidity when I got the baseline numbers and 83 degrees with 46% humidity when I dynoed the car with the headers on. No other changes were made to the car. Both dynos were done on a tank full of 10% ethanol 93 octane gasoline from the same Hess station. Ethanol free gasoline isn't available from any stations near where I live.
The results show an 18 HP gain peak and power gains everywhere with the headers over the X pipe with cats. Even the uncorrected result show a 17 HP gain peak and power gains everywhere. After these results, I really can't see why people believe that using an X pipe while keeping the stock manifolds gives the same power gains as headers on NA 3V S197's.
The only thing I'm curious about at this point is if there is mroe power to be had if the car is tuned for the cams.
The 2005 Mustang GT I bought came with a Bassani X pipe and aftermarket cats. I was interested in getting baseline numbers before I started modifying the car. I took the car to a Performance Specialties, Inc. in Pottstown, PA and dynoed the car. It produced 329 HP and 312 ft-lbs of torque. Power modifications on the car are:
C&L racer intake
Bassani X-pipe
SLP Loudmouth axle back
CMCV delete plates
Comp Cams NSR cams
Steeda underdrive pullies
SCT Xcal3 tuner with a Bama 93 octane tune
About a week and a half ago, I installed the Kooks headers with cats and X pipe. Then I took the car back to the same shop to have it dynoed again. The results were 347 HP and 320 ft-lbs of torque. Weather conditions for both days were similar. It was 80 degrees with 46% humidity when I got the baseline numbers and 83 degrees with 46% humidity when I dynoed the car with the headers on. No other changes were made to the car. Both dynos were done on a tank full of 10% ethanol 93 octane gasoline from the same Hess station. Ethanol free gasoline isn't available from any stations near where I live.
The results show an 18 HP gain peak and power gains everywhere with the headers over the X pipe with cats. Even the uncorrected result show a 17 HP gain peak and power gains everywhere. After these results, I really can't see why people believe that using an X pipe while keeping the stock manifolds gives the same power gains as headers on NA 3V S197's.
The only thing I'm curious about at this point is if there is mroe power to be had if the car is tuned for the cams.