I had a hole in my downpipe. The hole was about the size of the quarter slot on a parking meter. As I was unaware of the hole, I was custom tuned with the hole.

How much would this through off my tune? Do I need to be tuned again.

Thanks for your help.

 

I dont believe it would really affect your tune, but its probably taking a toll on performance. Get it welded at a mienkie or muffler shop.

 

The vendor replaced the downpipe with a new one (tuned with the hole). If it would take a "toll on performance" to have a hole, would it need to be re-tuned now that it has been corrected?

 

How was your tune done? If it was on a dyno, and the sensor for the A/F was stuck in your tail pipe, it might make a difference. Otherwise, I don' think it would change anything.

 

Yes, it was done on a dyno with the A/F in the tail pipe.