Question regarding exhaust cut-outs

[NHRA Super Gas]

It seems like every exhaust set up I have seen has the exhaust cut out as part of the package. Do most people open this up at the track? If so, is there a rule of thumb for the improvement...how much you'll pick up?

Thanks,

EW

 

[ttypewe4jim]

It seems like every exhaust set up I have seen has the exhaust cut out as part of the package. Do most people open this up at the track? If so, is there a rule of thumb for the improvement...how much you'll pick up?

Thanks,

EW

Alot of people have them because it usually allows the turbo to spool faster and sometimes a few more pounds of boost because the exhaust is restricting the flow.