Hi, Al. Since my street tune in April, I did not change or add mods to the engine, but i am looking into the Helix hi-flow and wonder if that alone would change my tune parameters enough to need a retune.

I know ideally the answer is yes, get it retuned for every new mod, but wondering if it's really gonna make me go lean enough to warrant the retune.

I'm just looking at the total cost versus the gains. The cat is 300. That's fine, but add a reflash and it's not worth the extra cost right now for 1 new mod.

If you feel it's absolutely nessessary, I will wait for more mods and get them all done at once and tuned. Thanks.

 

Of course every mod has some effect on tuning

However - the ecu does have a maf sensor and can compensate for additional air flow to some degree

Addition of a high flow cat is not really that significant a modification that would would need to get a complete retune

I think you should try and it and see how the car reacts

 

How about going from a Buschur 2.5" exhaust with stock cat and an AEM intake to a custom 3" exhaust with high flow cat and an Injen intake?

 

Injen intake requires a 100% new tune - just send mme in your ecu you get a free mail upgrade with your custom tune

 

What about going from a test pipe to a stock cat to get vET tested? Would it mess with the mail in flash or cause my car to fail the test?

 

Thank you, Al. I will try it. I know it's insignificant (5WHP or so), but I want to complete my exhaust system and move on to other things.

 

Cool man !

As for the other question - Dyno Flash will not effect closed loop emissions operation at all - UNLESS you change injectors

 

Thanks you Al.