Custom Tune Clarification

[Stumpuller6.5]

I will never remove my cats from a vehicle I own again. Severe stench, it doesn`t sound very good at idle (unless with headers) big loss in bottom end. There is no emmisions testing here but they can nab you for running without the equiptment installed.

If I were you and planned all the things you listed, install the high flows.

You truck will run with all those things on your list, likley your CEL will turn on, your computer will revert to a "base" calibrated tune (ignoring 02 signals) and it will not properly utilize all the items installed. A Custom tuning session will get every dollar out of those parts you`ve installed.

 

[bubbatrucklover]

Thanks for the input Clancy. I DEFINETLY don't want stench.

There is no question about getting a tune after the upgrades. I just wasn't sure about how well my truck could drive after swapping out components without one until getting it done.

 

[Texas Jim]

You mentioned SHORTY HEADERS earlier...
You may want to do some research on them before you buy them.
I have been told that shorty headers are usually not much better than the stock manifolds...
I have never owned any... just going on what I have been told...
I have had numerous sets of long tubes...
In my opinion...
Go LONG TUBE or GO HOME...

 

[svensk]

There would be no way I would pass a smog test. Good thing they got rid of that a long time ago.

 

[Hotty Toddy]

I'm in the middle of installing long tube headers on my truck, too. I've already got the K&N cold air intake. Went and bought the Pacesetter long tube headers and a Hypertech programmer.
My truck is a 2004 Chevy Z71, 5.3 liter. It has two cats, and sensors on both.
The Pacesetter headers and crossover piece does away with the cats, and there' really no place to relocate without a bunch of work.
I just got off the phone with Hypertech to see what I need to do when I remove the back sensors, and they said there was nothing they (or the programmer) could do. Everything had to be "compliant".
So....have I wasted time, money, and energy on this? I hate to think I need to buy TWO new cats and try to figure out how to install them.
Anybody got any ideas? I have a truck up on the rack and need to get it running!!
Thanks in advance......Todd

 

[Texas Jim]

I'm in the middle of installing long tube headers on my truck, too. I've already got the K&N cold air intake. Went and bought the Pacesetter long tube headers and a Hypertech programmer.
My truck is a 2004 Chevy Z71, 5.3 liter. It has two cats, and sensors on both.
The Pacesetter headers and crossover piece does away with the cats, and there' really no place to relocate without a bunch of work.
I just got off the phone with Hypertech to see what I need to do when I remove the back sensors, and they said there was nothing they (or the programmer) could do. Everything had to be "compliant".
So....have I wasted time, money, and energy on this? I hate to think I need to buy TWO new cats and try to figure out how to install them.
Anybody got any ideas? I have a truck up on the rack and need to get it running!!
Thanks in advance......Todd

see this thread...
It will THINK it is complaint...

http://www.truckmodcentral.com/forums/showthread.php?t=19447

 

[Stumpuller6.5]

IF your state does inspections, you`ll have to keep everything.

Otherwise you can run without, But would require custom tuning to turn off the CEL and get every penny out of those mods.

I personally hope you`d keep the exhaust emisions stuff. But that`s a personal choice.

 

[Bigredmariner]

I'm in the middle of installing long tube headers on my truck, too. I've already got the K&N cold air intake. Went and bought the Pacesetter long tube headers and a Hypertech programmer.
My truck is a 2004 Chevy Z71, 5.3 liter. It has two cats, and sensors on both.
The Pacesetter headers and crossover piece does away with the cats, and there' really no place to relocate without a bunch of work.
I just got off the phone with Hypertech to see what I need to do when I remove the back sensors, and they said there was nothing they (or the programmer) could do. Everything had to be "compliant".
So....have I wasted time, money, and energy on this? I hate to think I need to buy TWO new cats and try to figure out how to install them.
Anybody got any ideas? I have a truck up on the rack and need to get it running!!
Thanks in advance......Todd

Have your muffler guys weld in two extra O2 Sensor bungs, then you can go the route I did with the simulators.

 

[Black02Silverado]

Talk about bad exhaust smell, my 65 can make your eyes water and run you out of the garage if I leave it running in there very long before taking it out. It has fuel injection on it so I know it is running properly, was considering putting cats on it to clean it up and get rid of the smell but I don't drive it enough for that.

 

[Hotty Toddy]

Can you give me a little more detail, Big Red?
What kind of simulators? Where do you get them? How do they work sending a steady signal when the front one will be changing?