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Cat deletes

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I want to increase my power by a small amount, 15-25 HP. I do realize that is a lot with these engines. I do believe Ford did a great job maximizing the 5.0. It takes 6.2 ltrs from GM to make the power we do, or less I should say. So I believe milking NA power out of the Boss motor is tough. But I think and always have believed that the Cats are the biggest restriction in the exhaust. Sure you can get long tubes, mid pipes, mufflers etc, but the cats are the biggest restriction, period. Anyway, with that said I would like to delete my cats. But I only want a tune that corrects the O2 sensor, not anything else. In other words I want the factory tune to compensate and make power. I just don't trust any of the tunes yet that do more than compensate for little things. With variable cam timing and all that, I don't want to screw up. So, I guess what I'm asking is do the tunes for cat delete just handle O2 sensor issues and the factory computer still adjust and make HP?


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you can get those rear o2's turned off yes, leaving the stock tune in her.
but the red key will not be working. you are in essence downloading a new tune into the car still so
i would consider this.

i would get with shaun at AED as i think he is a better tuner than most.

enjoy
 
gremlinsteve said:
you can get those rear o2's turned off yes, leaving the stock tune in her.
but the red key will not be working. you are in essence downloading a new tune into the car still so
i would consider this.

i would get with shaun at AED as i think he is a better tuner than most.

enjoy

My main question is with the O2s turned off, will the factory tune compensate and make more power due to the reduced back pressure? I don't have the trackey, or plan on getting it quite yet.


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it should but again, i have experiance else where.
when one usually removes cats there is a full tune involved.

shaun at AED would be able to answer the question better. the ford uses a wide band so it should.
you can add long tubes and cat deletes and not need a retune. but you will have that cel for the rear o2 on.
and it will pick up power.
 
and for the record. if i was to do it over again i would use the stock header and add a somple cat delet pipe like your thinking. but i would remove the stock header and coat/wrap them for heat control.

that way i could go back to the stock cat pipe if i wanted to easier.

but i do like the sound the header gave me with that x pipe.
 
gremlinsteve said:
the ford uses a wide band so it should.
you can add long tubes and cat deletes and not need a retune. but you will have that cel for the rear o2 on.
and it will pick up power.
This is my understanding as well. I know Shaun at one point ran his car with stock headers and cat delete. He said removing the cats was good for close to 20 HP.
 
I agree with your goals and your logic. That's what I am doing as well although I am also adding the LTs. Justin at VMP is givimg me a "tune" that just shuts off the rear O2s and is also removing the speed limiter.
 
There's a lot more in there that can increase power getting to the ground.

Ford limits the power you are able to get to the tires unless on the Dyno.
These cars go into 'Dyno mode' when the front tires are not spinning and the rears are. Proper calibration can get a LOT more out of it, even if do I gains are minimal.

In other words, if you're going to get a tune for the off road pipe, might as well get a 'full' tune, not just have the rear O2's disabled.
 
Shaun@AED said:
There's a lot more in there that can increase power getting to the ground.

Ford limits the power you are able to get to the tires unless on the Dyno.
These cars go into 'Dyno mode' when the front tires are not spinning and the rears are. Proper calibration can get a LOT more out of it, even if do I gains are minimal.

In other words, if you're going to get a tune for the off road pipe, might as well get a 'full' tune, not just have the rear O2's disabled.
The gains I have seen advertised for the LTs and o/r X pipe are in the 35-40 rwhp range throughout the rpm band. How much additional power are you getting from further tuning with those same parts on a Boss?
 
cloud9 said:
The gains I have seen advertised for the LTs and o/r X pipe are in the 35-40 rwhp range throughout the rpm band. How much additional power are you getting from further tuning with those same parts on a Boss?

If they have LT's and o/r X pipe they will have a tune already. That 35-40 is with tuning.
 
After the Cat deletes are installed and the CEL ights up, will the CEL turn off on it's own if the cats are reinstalled? Or, will the dealer need to reset the computer? If the dealer needs to reset the computer, does that mean trak key would need to be reinstalled?
 
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Shaun@AED said:
There's a lot more in there that can increase power getting to the ground.

Ford limits the power you are able to get to the tires unless on the Dyno.
These cars go into 'Dyno mode' when the front tires are not spinning and the rears are. Proper calibration can get a LOT more out of it, even if do I gains are minimal.

In other words, if you're going to get a tune for the off road pipe, might as well get a 'full' tune, not just have the rear O2's disabled.

I'd love to hear more about this dyno mode.
 
Shaun@AED said:
There's a lot more in there that can increase power getting to the ground.

Ford limits the power you are able to get to the tires unless on the Dyno.
These cars go into 'Dyno mode' when the front tires are not spinning and the rears are. Proper calibration can get a LOT more out of it, even if do I gains are minimal.

In other words, if you're going to get a tune for the off road pipe, might as well get a 'full' tune, not just have the rear O2's disabled.

I wish I could keep the trak key tune and just turn off the O2 sensors. I guess that's still impossible.
 

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