If your car was custom tuned with a testpipe then after a month you want to change it from tp to hfcat, do you need to re-tune it?how about test pipe then to stock cat?

 

I would but Im a retune *****.

 

You should be fine. Imo, just retune for cat is waste $, but retune would be better.

 

Not necessary..

 

going from a cat to catless, definitely. You'll start throwing p1235's. Going the other way? Maybe.

 

right now i dont have any codes on TP, how much hp did you have on your tune on stock cat?

 

i don't understand your question (honestly I have trouble understanding most of what you write, what's your first language?)

I never tuned with the stock cat. I initially tuned with a high flow cat and then switched to a test pipe and hit the airflow limits (p1235). This was a dyno tune from Cobb at the time.

 

If he would add a d in the appropriate places I could read it.

 

Have you logged your car and watched for knock? Cars with cats generally won't take as much timing.

 

I'm sure, he is asking...
Orig post: is he ok to going back to stock or hfc with his tuned(tuned for tp) or needs retune for hfc or stock cat

Second post: how much you made hp with stock cat.

Correct me if I'm wrong...