Is a tune neccesary after new headers added

[kbvaughn]

I have purchased JBA shorty headers and an underdrive pulley kit with the intention of having professinal install in the coming weeks. Is a tune needed after this modification and if so what would be the most beneficial? Thanks in advance for your suggestions.

[kahmann]

I have purchased JBA shorty headers and an underdrive pulley kit with the intention of having professinal install in the coming weeks. Is a tune needed after this modification and if so what would be the most beneficial? Thanks in advance for your suggestions.

Some will say yes, some say no. I'd get the custom tune either way. It's a big advantage over stock.

The shortys are a waste of money, IMO. The UD pulleys are great, but do not require a new tune.

As for which tune, I highly recommend Bamachips race tune. Good luck.

 

Ken

[ilmor]

From what I have read on the forum, a custom dyno tune is the way to go next.

[ARMORINE]

shortys a are a waste of money for the 4.6, theres no advantage i have seen with them, longtubes are the way to go if your doing headers

[2kmelat]

I had JBA shorty on my 06 gt and it was a wast of $ got the JBA long and there was a big diff in sound a little in power. now I have the JBA long on my GT500 with out cats and wow.

[socalwrench]

Warning- technical words used:

 

The primary reason the 4.6L 3v needs a new tune is because of the 'strict' fuel management program. Along with a sensitive MAF sensor- your air/fuel ratio can be thrown way off. For instance, if you are changing air intakes, intake manifolds, or cams- you WILL need a reflash (tune). Some companies have addressed this with aftermarket MAF sensors with satisfactory results. However, I would retain the use of the FoMoCo MAF sensor with a reflash that is designed for your intake (and/or engine) combination.

 

Simply removing restriction after the combustion chamber (such as the exhaust) will not affect your engine the same way that changing intake parts will. Your factory oxygen sensors will sense oxygen content, regardless of the volume of air passing by them. Afterall, your catalytic converters are still a huge restriction. As some have already said- installing long tube headers and high flow (less efficient) or no cats will give you a large power increase. So, as a general rule- exhaust modifications do NOT require a reflash. However, removing the cats may throw an engine code (because the downstream sensors may see some HCs- unburned fuel).

 

Lastly, IF you are doing multiple modifications to the engine, than $100+/hr for a dynometer and custom tune is well worth the money and hassle of making every work together. Just don't be surprised if your dealer voids your warranty.

[kbvaughn]

shortys a are a waste of money for the 4.6, theres no advantage i have seen with them, longtubes are the way to go if your doing headers

 

I do not believe that long tube headers would pass emissions in my state. My 08SGT is my daily driver (because I can't leave it parked in a garage). It seems that most believe the shorty's are a waste of money so perhaps I will return them and simply have the under drive pulley kit installed.

[ilmor]

What about long tubes with cats? I know they are available.

[blueshawk]

I have purchased JBA shorty headers and an underdrive pulley kit with the intention of having professinal install in the coming weeks. Is a tune needed after this modification and if so what would be the most beneficial? Thanks in advance for your suggestions.

 

I think the power gains for shortys is in the midrange RPM where it's most useful. See the excerpt from Mustang Monthly:

 

Ford Mustang BBK Headers - How To Install '05-'07 Headers

 

On the Dyno

 

If you only look at the peak horsepower gain, shown in bold numbers, then sure, the headers only gained 4 hp at the wheels. But you'd be missing the large majority of what the headers really did for our '06 Mustang GT test car.

 

Study the dyno charts to discern the real benefits of the BBK headers: improvements in torque output. For example, look at the results at 3,000 rpm. The car in the baseline test made 265.6 lb-ft. With the headers, the figure jumped to 283.2, an improvement of 17.6 lb-ft.

 

Torque is what you feel on the street, and having more of it in the midrange is what's important for slipping through traffic and getting up freeway on-ramps. At various speeds, power output isn't too bad either. Again looking at 3,000 rpm, the baseline test result is 151.7 hp. With the headers in place, output jumped to 161.8 hp for a gain of more than 10 hp.

 

Additionally, recall that we're only testing the headers here. With BBK's crossover pipe in place, figure another 10 hp or so improvement across the board or well over 300 hp at the wheels on this car already equipped with a BBK throttle body and cold-air kit. Note too that the power and torque peaks with the headers were at slightly lower engine speeds, which makes the power all the more usable on the street. Furthermore, with the headers, the torque curve stayed over 300 lb-ft from 3,750 all the way to 5,000 rpm, another notable improvement over the baseline test.

 

Baseline: '06 Mustang GT with

BBK throttle body and cold-air kit

RPM POWER TORQUE

2,250 114.0 266.2

2,500 127.3 267.5

2,750 139.3 266.1

3,000 151.7 265.6

3,250 166.0 268.2

3,500 188.1 282.2

3,750 207.7 290.9

4,000 229.9 301.9

4,250 246.5 304.7

4,500 261.4 305.1

4,750 271.2 299.8

5,000 284.2 298.5

5,250 292.2 292.3

5,500 292.4 279.2

5,750 292.0 266.7

6,000 291.0 254.8

 

 

BBK headers

RPM POWER TORQUE

2,250 118.3 276.0

2,500 131.9 277.0

2,750 148.0 282.8

3,000 161.8 283.2

3,250 175.5 283.6

3,500 197.9 296.9

3,750 214.7 300.7

4,000 236.0 309.8

4,250 255.6 315.8

4,500 270.0 315.1

4,750 279.9 309.5

5,000 291.9 306.6

5,250 296.4 296.5

5,500 286.2 273.3

5,750 286.8 262.0

6,000 286.9 251.1

 

 

Shortys with a undrive crankpulley, aluminum drive shaft and an electric water pump, all finished with a custom dyno tune is the way I'm going to go when my warranty expires next year.

[WildAzCat]

I primarily went with JBA shorty because I hate seeing the ugly factory headers. Maybe what ever HP gain I got was in my head but I'm okay with that.

[socalwrench]

Most exhaust headers are NOT emissions legal, nor do they carry a CARB number. Anything that could change or alter the orientation of the 02 sensors could affect emissions. This is why companies have to prove that higher flowing headers do NOT pollute. Most of the long tube headers reposition or remove the catalytic converters, and, therefore, will never be approved for street use.

 

Also, remember that primary tube diameters play as much as role on the engine's powerband as much as the total length does. As a general rule, longer headers will make more horsepower at a higher rpm than short length headers. OEMs keep headers short for many reasons- less material cost, easier fitment, more torque.

I have been looking at the FR headers for quite some time. I haven't purchased them because (according to my research)- cheaper power can be made from the exhaust in terms of mufflers and high flow cats. Perhaps once my warranty expires, I will install long tube headers with no cats.